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1
Lan, Jingqiu, Jinzhe Zhang, Rongrong Yuan, Hao Yu, Fengying An, Linhua Sun, Haodong Chen et al. "TCP transcription factors suppress cotyledon trichomes by impeding a cell differentiation-regulating complex". Plant Physiology 186, n.º 1 (12 de febrero de 2021): 434–51. http://dx.doi.org/10.1093/plphys/kiab053.
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Abstract Trichomes are specialized epidermal cells that act as barriers against biotic and abiotic stresses. Although the formation of trichomes on hairy organs is well studied, the molecular mechanisms of trichome inhibition on smooth organs are still largely unknown. Here, we demonstrate that the CINCINNATA (CIN)-like TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factors inhibit the formation of trichomes on cotyledons in Arabidopsis (Arabidopsis thaliana). The tcp2/3/4/5/10/13/17 septuple mutant produces cotyledons with ectopic trichomes on the adaxial sides. The expression patterns of TCP genes are developmentally regulated during cotyledon development. TCP proteins directly interact with GLABRA3 (GL3), a key component of the MYB transcription factor/basic helix–loop–helix domain protein/WD40-repeat proteins (MYB–bHLH–WD40, MBW) complex essential for trichome formation, to interfere with the transactivation activity of the MBW complex in cotyledons. TCPs also disrupt the MBW complex–R3 MYB negative feedback loop by directly promoting the expression of R3 MYB genes, which enhance the repression of the MBW complex. Our findings reveal a molecular framework in which TCPs suppress trichome formation on adaxial sides of cotyledons by repressing the activity of the MBW complex at the protein level and the transcripts of R3 MYB genes at the transcriptional level.
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Wei, Zelou, Yalong Cheng, Chenchen Zhou, Dong Li, Xin Gao, Shuoxin Zhang y Mingxun Chen. "Genome-Wide Identification of Direct Targets of the TTG1–bHLH–MYB Complex in Regulating Trichome Formation and Flavonoid Accumulation in Arabidopsis Thaliana". International Journal of Molecular Sciences 20, n.º 20 (10 de octubre de 2019): 5014. http://dx.doi.org/10.3390/ijms20205014.
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Extensive studies have shown that the MBW complex consisting of three kinds of regulatory proteins, MYB and basic helix–loop–helix (bHLH) transcription factors and a WD40 repeat protein, TRANSPARENT TESTA GLABRA1 (TTG1), acts in concert to promote trichome formation and flavonoid accumulation in Arabidopsis thaliana. TTG1 functions as an essential activator in these two biological processes. However, direct downstream targets of the TTG1-dependent MBW complex have not yet been obtained in the two biological processes at the genome-wide level in A. thaliana. In the present study, we found, through RNA sequencing and quantitative real-time PCR analysis, that a great number of regulatory and structural genes involved in both trichome formation and flavonoid accumulation are significantly downregulated in the young shoots and expanding true leaves of ttg1-13 plants. Post-translational activation of a TTG1-glucocorticoid receptor fusion protein and chromatin immunoprecipitation assays demonstrated that these downregulated genes are directly or indirectly targeted by the TTG1-dependent MBW complex in vivo during trichome formation and flavonoid accumulation. These findings further extend our understanding of the role of TTG1-dependent MBW complex in the regulation of trichome formation and flavonoid accumulation in A. thaliana.
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Zhang, Bipei, Divykriti Chopra, Andrea Schrader y Martin Hülskamp. "Evolutionary comparison of competitive protein-complex formation of MYB, bHLH, and WDR proteins in plants". Journal of Experimental Botany 70, n.º 12 (9 de abril de 2019): 3197–209. http://dx.doi.org/10.1093/jxb/erz155.
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Abstract A protein complex consisting of a MYB, basic Helix-Loop-Helix, and a WDR protein, the MBW complex, regulates five traits, namely the production of anthocyanidin, proanthocyanidin, and seed-coat mucilage, and the development of trichomes and root hairs. For complexes involved in trichome and root hair development it has been shown that the interaction of two MBW proteins can be counteracted by the respective third protein (called competitive complex formation). We examined competitive complex formation for selected MBW proteins from Arabidopsis thaliana, Arabis alpina, Gossypium hirsutum, Petunia hybrida, and Zea mays. Quantitative analyses of the competitive binding of MYBs and WDRs to bHLHs were done by pull-down assays using ProtA- and luciferase-tagged proteins expressed in human HEC cells. We found that some bHLHs show competitive complex formation whilst others do not. Competitive complex formation strongly correlated with a phylogenetic tree constructed with the bHLH proteins under investigation, suggesting a functional relevance. We demonstrate that this different behavior can be explained by changes in one amino acid and that this position is functionally relevant in trichome development but not in anthocyanidin regulation.
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Zhang, T. K. y Z. H. Yuan. "Quick convergent evolution of MBW complex for pomegranate fruit coloration". Acta Horticulturae, n.º 1254 (octubre de 2019): 135–42. http://dx.doi.org/10.17660/actahortic.2019.1254.21.
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Davies, Kevin M., Nick W. Albert y Kathy E. Schwinn. "From landing lights to mimicry: the molecular regulation of flower colouration and mechanisms for pigmentation patterning". Functional Plant Biology 39, n.º 8 (2012): 619. http://dx.doi.org/10.1071/fp12195.
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Flower colour is a key component for plant signaling to pollinators and a staggering variety of colour variations are found in nature. Patterning of flower colour, such as pigment spots or stripes, is common and is important in promoting pollination success. Developmentally programmed pigmentation patterns are of interest with respect to the evolution of specialised plant–pollinator associations and as models for dissecting regulatory signaling in plants. This article reviews the occurrence and function of flower colour patterns, as well as the molecular genetics of anthocyanin pigmentation regulation. The transcription factors controlling anthocyanin biosynthesis have been characterised for many species and an ‘MBW’ regulatory complex of R2R3MYB, bHLH and WD-Repeat proteins is of central importance. In particular, R2R3MYBs are key determinants of pigmentation intensity and patterning in plants. Progress is now being made on how environmental or developmental signal pathways may in turn control the production of the MBW components. Furthermore, additional regulatory proteins that interact with the MBW activation complex are being identified, including a range of proteins that repress complex formation or action, either directly or indirectly. This review discusses some of the recent data on the regulatory factors and presents models of how patterns may be determined.
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Sun, Xingming, Zhanying Zhang, Jinjie Li, Hongliang Zhang, Youliang Peng y Zichao Li. "Uncovering Hierarchical Regulation among MYB-bHLH-WD40 Proteins and Manipulating Anthocyanin Pigmentation in Rice". International Journal of Molecular Sciences 23, n.º 15 (26 de julio de 2022): 8203. http://dx.doi.org/10.3390/ijms23158203.
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Anthocyanins accumulate in various organs of rice, and the regulatory genes involved in pigmentation of specific organs, such as pericarp, hull, leaf, apiculus, and stigma have been elucidated. However, the corresponding gene for rice culm pigmentation has not been clarified. The well-known MYB-bHLH-WD40 (MBW) complex plays vital role in regulating the anthocyanin biosynthesis pathway in plants. However, the core members of MBW and the hierarchical regulation between these members are not fully elucidated in rice. Here, by map-based cloning, we identified the culm-specific pigmentation gene S1 whose alleles are also known for hull/pericarp pigmentation. We also clarified that one WD40 protein encoding gene, WA1, is indispensable for anthocyanin biosynthesis in rice. In the cascading regulation among MBW members, S1 (bHLH) acts as the master gene by activating the expression of C1 (MYB), and then C1 activates the expression of WA1 (WD40), which is unique in plant species. This enables MBW members to be coordinated in a common way to efficiently regulate anthocyanin biosynthesis genes. Based on these studies, we explored the minimal gene set required for anthocyanin biosynthesis in rice. These findings will help us design new rice varieties with anthocyanin accumulation in specific organs as needed.
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Li, Yueqing, Xiaotong Shan, Linna Tong, Chao Wei, Keyu Lu, Shuying Li, Shadrack Kimani, Shucai Wang, Li Wang y Xiang Gao. "The Conserved and Particular Roles of the R2R3-MYB Regulator FhPAP1 from Freesia hybrida in Flower Anthocyanin Biosynthesis". Plant and Cell Physiology 61, n.º 7 (11 de mayo de 2020): 1365–80. http://dx.doi.org/10.1093/pcp/pcaa065.
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Abstract Anthocyanin biosynthesis is mainly controlled by MYB–bHLH–WD40 (MBW) complexes that modulate the expression of anthocyanin biosynthetic genes (ABGs). The MYB regulators involved in anthocyanin biosynthesis arose early during plant evolution and thus might function divergently in different evolutionary lineages. Although the anthocyanin-promoting R2R3-MYB regulators in eudicots have been comprehensively explored, little consensus has been reached about functional discrepancies versus conservation among MYB regulators from different plant lineages. Here, we integrated transcriptome analysis, gene expression profiles, gain-of-function experiments and transient protoplast transfection assays to functionally characterize the monocot Freesia hybrida anthocyanin MYB regulator gene FhPAP1, which showed correlations with late ABGs. FhPAP1 could activate ABGs as well as TT8-clade genes FhTT8L, AtTT8 and NtAN1 when overexpressed in Freesia, Arabidopsis and tobacco, respectively. Consistently, FhPAP1 could interact with FhTT8L and FhTTG1 to form the conserved MBW complex and shared similar target genes with its orthologs from Arabidopsis. Most prominently, FhPAP1 displayed higher transactivation capacity than its homologs in Arabidopsis and tobacco, which was instantiated in its powerful regulation on ABGs. Moreover, we found that FhPAP1 might be the selected gene during the domestication and rapid evolution of the wild Freesia species to generate intensive flower pigmentation. These results showed that while the MBW complex was highly evolutionarily conserved between tested monocot and core eudicot plants, participating MYB regulators showed functional differences in transactivation capacity according to their activation domain and played important roles in the flower coloration domestication and evolution of angiosperms.
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Tian, Yue, Jingjing Du, Huaitong Wu, Xueying Guan, Weihang Chen, Yan Hu, Lei Fang et al. "The transcription factor MML4_D12 regulates fiber development through interplay with the WD40-repeat protein WDR in cotton". Journal of Experimental Botany 71, n.º 12 (2 de marzo de 2020): 3499–511. http://dx.doi.org/10.1093/jxb/eraa104.
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Abstract In planta, a vital regulatory complex, MYB–basic helix–loop–helix (bHLH)–WD40 (MBW), is involved in trichome development and synthesis of anthocyanin and proanthocyanin in Arabidopsis. Usually, WD40 proteins provide a scaffold for protein–protein interaction between MYB and bHLH proteins. Members of subgroup 9 of the R2R3 MYB transcription factors, which includes MYBMIXTA-Like (MML) genes important for plant cell differentiation, are unable to interact with bHLH. In this study, we report that a cotton (Gossypium hirsutum) seed trichome or lint fiber-related GhMML factor, GhMML4_D12, interacts with a diverged WD40 protein (GhWDR) in a process similar to but different from that of the MBW ternary complex involved in Arabidopsis trichome development. Amino acids 250–267 of GhMML4_D12 and the first and third WD40 repeat domains of GhWDR determine their interaction. GhWDR could rescue Arabidopsis ttg1 to its wild type, confirming its orthologous function in trichome development. Our findings shed more light towards understanding the key role of the MML and WD40 families in plants and in the improvement of cotton fiber production.
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Zhao, Xuecheng, Yueran Zhang, Tuan Long, Shouchuang Wang y Jun Yang. "Regulation Mechanism of Plant Pigments Biosynthesis: Anthocyanins, Carotenoids, and Betalains". Metabolites 12, n.º 9 (16 de septiembre de 2022): 871. http://dx.doi.org/10.3390/metabo12090871.
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Anthocyanins, carotenoids, and betalains are known as the three major pigments in the plant kingdom. Anthocyanins are flavonoids derived from the phenylpropanoid pathway. They undergo acylation and glycosylation in the cytoplasm to produce anthocyanin derivatives and deposits in the cytoplasm. Anthocyanin biosynthesis is regulated by the MBW (comprised by R2R3-MYB, basic helix-loop-helix (bHLH) and WD40) complex. Carotenoids are fat-soluble terpenoids whose synthetic genes also are regulated by the MBW complex. As precursors for the synthesis of hormones and nutrients, carotenoids are not only synthesized in plants, but also synthesized in some fungi and bacteria, and play an important role in photosynthesis. Betalains are special water-soluble pigments that exist only in Caryophyllaceae plants. Compared to anthocyanins and carotenoids, the synthesis and regulation mechanism of betalains is simpler, starting from tyrosine, and is only regulated by MYB (myeloblastosis). Recently, a considerable amount of novel information has been gathered on the regulation of plant pigment biosynthesis, specifically with respect to aspects. In this review, we summarize the knowledge and current gaps in our understanding with a view of highlighting opportunities for the development of pigment-rich plants.
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Peniche-Pavía, Héctor A., Tereso J. Guzmán, Jesús M. Magaña-Cerino, Carmen M. Gurrola-Díaz y Axel Tiessen. "Maize Flavonoid Biosynthesis, Regulation, and Human Health Relevance: A Review". Molecules 27, n.º 16 (13 de agosto de 2022): 5166. http://dx.doi.org/10.3390/molecules27165166.
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Maize is one of the most important crops for human and animal consumption and contains a chemical arsenal essential for survival: flavonoids. Moreover, flavonoids are well known for their beneficial effects on human health. In this review, we decided to organize the information about maize flavonoids into three sections. In the first section, we include updated information about the enzymatic pathway of maize flavonoids. We describe a total of twenty-one genes for the flavonoid pathway of maize. The first three genes participate in the general phenylpropanoid pathway. Four genes are common biosynthetic early genes for flavonoids, and fourteen are specific genes for the flavonoid subgroups, the anthocyanins, and flavone C-glycosides. The second section explains the tissue accumulation and regulation of flavonoids by environmental factors affecting the expression of the MYB-bHLH-WD40 (MBW) transcriptional complex. The study of transcription factors of the MBW complex is fundamental for understanding how the flavonoid profiles generate a palette of colors in the plant tissues. Finally, we also include an update of the biological activities of C3G, the major maize anthocyanin, including anticancer, antidiabetic, and antioxidant effects, among others. This review intends to disclose and integrate the existing knowledge regarding maize flavonoid pigmentation and its relevance in the human health sector.
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Garrido-Bigotes, Adrián, Marcela Torrejón, Roberto Solano y Carlos R. Figueroa. "Interactions of JAZ Repressors with Anthocyanin Biosynthesis-Related Transcription Factors of Fragaria × ananassa". Agronomy 10, n.º 10 (16 de octubre de 2020): 1586. http://dx.doi.org/10.3390/agronomy10101586.
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Strawberry fruits are rich in flavonoids like proanthocyanidins and anthocyanins. Their biosynthesis and accumulation are controlled by the MYB-bHLH-WD40 (MBW) transcriptional complex, which is mainly formed by basic helix-loop-helix (bHLH) and MYB transcription factors (TFs). In Arabidopsis thaliana both bHLH and MYB TFs are repressed by JASMONATE ZIM-DOMAIN (JAZ) proteins, the key repressors of the jasmonate-signaling pathway. The aim of this research was the characterization of the FaJAZ1/8.1/9/10 proteins and molecular targets of signaling components and anthocyanin biosynthesis-related TFs of Fragaria × ananassa by protein–protein interactions. For this, domain compositions were studied by multiple alignments and phylogenetic analyses, while interactions were analyzed by yeast two-hybrid (Y2H) assays. We detected high conservation of FaJAZ proteins and jasmonate-signaling components, as well as FabHLHs and FaMYB10 TFs. Moreover, we report the F. × ananassa YABBY1 (FaYAB1) TF, which is related to anthocyanin biosynthesis in Arabidopsis, showed high conservation of functional domains. We demonstrated that FaJAZ repressors interacted with F. × ananassa NOVEL INTERACTOR OF JAZ (FaNINJA), FaMYC2, and JASMONATE ASSOCIATED MYC2-LIKE (FaJAM) proteins. Besides, transcription factors of MBW-complex like FabHLH3, FabHLH33, and FaMYB10, together with FaYAB1, were molecular targets of FaJAZ repressors, exhibiting specificity or redundancy of interaction depending on particular FaJAZ protein. Overall, these results suggest that interactions of jasmonate-signaling components are fully conserved, and anthocyanin biosynthesis might be regulated by JAZ repressors in F. × ananassa.
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Krylova, E. A. y A. S. Mikhailova. "Regulation of flavonoid biosynthesis in representatives of the tribe Phaseoleae DC." Plant Biotechnology and Breeding 4, n.º 3 (23 de diciembre de 2021): 15–25. http://dx.doi.org/10.30901/2658-6266-2021-3-o1.
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Flavonoids play a crucial role in plant metabolism. Many of them have antioxidant activity, and they are also pigments that render a variety of colors to plant tissues. Foods rich in flavonoid compounds are considered as functional components of a healthy diet. Currently, there is an increased interest in studying genetic mechanisms underlying the coloration of plants. Flavonoid biosynthesis pathways are controlled by two groups of genes. Structural genes encode enzymes, while regulatory genes are responsible for transcription factors that activate the expression of structural genes. Transcription factors that belong to R2R3-Myb, bHLH-Myc and WDR families form the ternary MBW complex, which is involved in regulating the expression of structural genes of flavonoid biosynthesis. The mechanisms of regulation of the anthocyanins and proanthocyanidin biosynthesis by the MBW complex are described in detail for the model plant Arabidopsis thaliana L. This review summarizes data on the regulation of phenolic pigment biosynthesis and the features of phenolic pigment accumulation in plant tissues in the main representatives of the Phaseoleae tribe: soybean Glycine max (L.) Merr., common bean Phaseolus vulgaris L., adzuki bean Vigna angularis (Willd.) Ohwi & Ohashi, and cowpea V. unguiculata (L.) Walp. The species discussed in this review are the most important food legumes in many countries of the world and they comprise the staple food in diets of millions of people. Identification and characterization of the genes controlling the flavonoid biosynthesis pathways are necessary for successful breeding of modern varieties with an increased dietary value. Identification of the flavonoid accumulation patterns is essential for solving the problem of broadening the diversity of plant products.
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Wang, Xiaoping, Wei Wang, Siyu Chen, Yuji Lian y Shucai Wang. "Tropaeolum majus R2R3 MYB Transcription Factor TmPAP2 Functions as a Positive Regulator of Anthocyanin Biosynthesis". International Journal of Molecular Sciences 23, n.º 20 (17 de octubre de 2022): 12395. http://dx.doi.org/10.3390/ijms232012395.
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Anthocyanins are an important group of water-soluble and non-toxic natural pigments with antioxidant and anti-inflammatory properties that can be found in flowers, vegetables, and fruits. Anthocyanin biosynthesis is regulated by several different types of transcription factors, including the WD40-repeat protein Transparent Testa Glabra 1 (TTG1), the bHLH transcription factor Transparent Testa 8 (TT8), Glabra3 (GL3), Enhancer of GL3 (EGL3), and the R2R3 MYB transcription factor Production of Anthocyanin Pigment 1 (PAP1), PAP2, MYB113, and MYB114, which are able to form MYB-bHLH-WD40 (MBW) complexes to regulate the expression of late biosynthesis genes (LBGs) in the anthocyanin biosynthesis pathway. Nasturtium (Tropaeolum majus) is an edible flower plant that offers many health benefits, as it contains numerous medicinally important ingredients, including anthocyanins. By a comparative examination of the possible anthocyanin biosynthesis regulator genes in nasturtium varieties with different anthocyanin contents, we found that TmPAP2, an R2R3 MYB transcription factor gene, is highly expressed in “Empress of India”, a nasturtium variety with high anthocyanin content, while the expression of TmPAP2 in Arabidopsis led to the overproduction of anthocyanins. Protoplast transfection shows that TmPAP2 functions as a transcription activator; consistent with this finding, some of the biosynthesis genes in the general phenylpropanoid pathway and anthocyanin biosynthesis pathway were highly expressed in “Empress of India” and the 35S:TmPAP2 transgenic Arabidopsis plants. However, protoplast transfection indicates that TmPAP2 may not be able to form an MBW complex with TmGL3 and TmTTG1. These results suggest that TmPAP2 may function alone as a key regulator of anthocyanin biosynthesis in nasturtiums.
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Jacob, Pierre, Gwilherm Brisou, Marion Dalmais, Johanne Thévenin, Froukje van der Wal, David Latrasse, Ravi Suresh Devani et al. "The Seed Development Factors TT2 and MYB5 Regulate Heat Stress Response in Arabidopsis". Genes 12, n.º 5 (15 de mayo de 2021): 746. http://dx.doi.org/10.3390/genes12050746.
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HEAT SHOCK FACTOR A2 (HSFA2) is a regulator of multiple environmental stress responses required for stress acclimation. We analyzed HSFA2 co-regulated genes and identified 43 genes strongly co-regulated with HSFA2 during multiple stresses. Motif enrichment analysis revealed an over-representation of the site II element (SIIE) in the promoters of these genes. In a yeast 1-hybrid screen with the SIIE, we identified the closely related R2R3-MYB transcription factors TT2 and MYB5. We found overexpression of MYB5 or TT2 rendered plants heat stress tolerant. In contrast, tt2, myb5, and tt2/myb5 loss of function mutants showed heat stress hypersensitivity. Transient expression assays confirmed that MYB5 and TT2 can regulate the HSFA2 promoter together with the other members of the MBW complex, TT8 and TRANSPARENT TESTA GLABRA 1 (TTG1) and that the SIIE was involved in this regulation. Transcriptomic analysis revealed that TT2/MYB5 target promoters were enriched in SIIE. Overall, we report a new function of TT2 and MYB5 in stress resistance and a role in SIIE-mediated HSFA2 regulation.
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Kim, JiYeon, Da-Hye Kim, Jong-Yeol Lee y Sun-Hyung Lim. "The R3-Type MYB Transcription Factor BrMYBL2.1 Negatively Regulates Anthocyanin Biosynthesis in Chinese Cabbage (Brassica rapa L.) by Repressing MYB–bHLH–WD40 Complex Activity". International Journal of Molecular Sciences 23, n.º 6 (21 de marzo de 2022): 3382. http://dx.doi.org/10.3390/ijms23063382.
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Chinese cabbage (Brassica rapa L.) leaves are purple in color due to anthocyanin accumulation and have nutritional and aesthetic value, as well as antioxidant properties. Here, we identified the R3 MYB transcription factor BrMYBL2.1 as a key negative regulator of anthocyanin biosynthesis. A Chinese cabbage cultivar with green leaves harbored a functional BrMYBL2.1 protein, designated BrMYBL2.1-G, with transcriptional repressor activity of anthocyanin biosynthetic genes. By contrast, BrMYBL2.1 from a Chinese cabbage cultivar with purple leaves carried a poly(A) insertion in the third exon of the gene, resulting in the insertion of multiple lysine residues in the predicted protein, designated BrMYBL2.1-P. Although both BrMYBL2.1 variants localized to the nucleus, only BrMYBL2.1-G interacted with its cognate partner BrTT8. Transient infiltration assays in tobacco leaves revealed that BrMYBL2.1-G, but not BrMYBL2.1-P, actively represses pigment accumulation by inhibiting the transcription of anthocyanin biosynthetic genes. Transient promoter activation assay in Arabidopsis protoplasts verified that BrMYBL2.1-G, but not BrMYBL2.1-P, can repress transcriptional activation of BrCHS and BrDFR, which was activated by co-expression with BrPAP1 and BrTT8. We determined that BrMYBL2.1-P may be more prone to degradation than BrMYBL2.1-G via ubiquitination. Taken together, these results demonstrate that BrMYBL2.1-G blocks the activity of the MBW complex and thus represses anthocyanin biosynthesis, whereas the variant BrMYBL2.1-P from purple Chinese cabbage cannot, thus leading to higher anthocyanin accumulation.
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Potdar, Bhargav, Stéphane Graff y Björn Kiefer. "Numerical Analysis and Experimental Validation of the Thermo-Mechanical Flow Behaviour of the Hot Stamping Steel MBW® 1500". Key Engineering Materials 639 (marzo de 2015): 213–20. http://dx.doi.org/10.4028/www.scientific.net/kem.639.213.
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In virtual design of the hot stamping process, a reliable description of the material flow behaviour is an important input to ensure accurate estimations of the parts feasibility. Currently, to characterise the hot stamping material’s flow behaviour at elevated temperatures, tensile and upsetting tests are available. The measurement of the flow behaviour out of such tests, which is generally temperature and strain rate dependent, still remains a complex task. Therefore traditional methods to measure flow curves out of such measurements are not necessarily precise enough. In this contribution the authors focus on non-isothermal conductive tensile tests of the manganese-boron steel MBW® 1500 in order to understand its flow behaviour at elevated temperature. Numerical calculations using Finite Element Method (FEM) of the tests itself with correct boundary conditions as well as for all necessary phenomena are used to identify accurately the material’s flow curves by use of inverse optimisation. Finally, for validation purpose the identified flow curves out of the optimisation method were used to simulate the hot stamping of two different parts. Both geometries were chosen such that various strain paths are covered i.e. uniaxial tension to plane strain.
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Delgado, Laura, Paz Zúñiga, Nicolás Figueroa, Edgar Pastene, Hugo Escobar-Sepúlveda, Pablo Figueroa, Adrián Garrido-Bigotes y Carlos Figueroa. "Application of a JA-Ile Biosynthesis Inhibitor to Methyl Jasmonate-Treated Strawberry Fruit Induces Upregulation of Specific MBW Complex-Related Genes and Accumulation of Proanthocyanidins". Molecules 23, n.º 6 (13 de junio de 2018): 1433. http://dx.doi.org/10.3390/molecules23061433.
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Amato, Alessandra, Erika Cavallini, Amanda R. Walker, Mario Pezzotti, Mattijs Bliek, Francesca Quattrocchio, Ronald Koes et al. "The MYB 5‐driven MBW complex recruits a WRKY factor to enhance the expression of targets involved in vacuolar hyper‐acidification and trafficking in grapevine". Plant Journal 99, n.º 6 (27 de junio de 2019): 1220–41. http://dx.doi.org/10.1111/tpj.14419.
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Zhou, Zheng, Alex Windhorst, Dirk Schenke y Daguang Cai. "RNAseq-Based Working Model for Transcriptional Regulation of Crosstalk between Simultaneous Abiotic UV-B and Biotic Stresses in Plants". Genes 14, n.º 2 (17 de enero de 2023): 240. http://dx.doi.org/10.3390/genes14020240.
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Plants adjust their secondary metabolism by altering the expression of corresponding genes to cope with both abiotic and biotic stresses. In the case of UV-B radiation, plants produce protective flavonoids; however, this reaction is impeded during pattern-triggered immunity (PTI) induced by pathogens. Pathogen attack can be mimicked by the application of microbial associated molecular patterns (e.g., flg22) to study crosstalk between PTI and UV-B-induced signaling pathways. Switching from Arabidopsis cell cultures to in planta studies, we analyzed whole transcriptome changes to gain a deeper insight into crosstalk regulation. We performed a comparative transcriptomic analysis by RNAseq with four distinct mRNA libraries and identified 10778, 13620, and 11294 genes, which were differentially expressed after flg22, UV-B, and stress co-treatment, respectively. Focusing on genes being either co-regulated with the UV-B inducible marker gene chalcone synthase CHS or the flg22 inducible marker gene FRK1 identified a large set of transcription factors from diverse families, such as MYB, WRKY, or NAC. These data provide a global view of transcriptomic reprogramming during this crosstalk and constitute a valuable dataset for further deciphering the underlying regulatory mechanism(s), which appear to be much more complex than previously anticipated. The possible involvement of MBW complexes in this context is discussed.
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Ballico, E. "Infinite-dimensional complex projective spaces and complete intersections". Mathematica Bohemica 131, n.º 4 (2006): 419–25. http://dx.doi.org/10.21136/mb.2006.133969.
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Mo, Rongli, Guangming Han, Zhixian Zhu, Jemaa Essemine, Zhaoxia Dong, Yong Li, Wen Deng, Mingnan Qu, Cheng Zhang y Cui Yu. "The Ethylene Response Factor ERF5 Regulates Anthocyanin Biosynthesis in ‘Zijin’ Mulberry Fruits by Interacting with MYBA and F3H Genes". International Journal of Molecular Sciences 23, n.º 14 (9 de julio de 2022): 7615. http://dx.doi.org/10.3390/ijms23147615.
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Ethylene promotes ripening in fruits as well as the biosynthesis of anthocyanins in plants. However, the question of which ethylene response factors (ERFs) interact with the genes along the anthocyanin biosynthesis pathway is yet to be answered. Herein, we conduct an integrated analysis of transcriptomes and metabolome on fruits of two mulberry genotypes (‘Zijin’, ZJ, and ‘Dashi’, DS, with high and low anthocyanin abundance, respectively) at different post-flowering stages. In total, 1035 upregulated genes were identified in ZJ and DS, including MYBA in the MBW complex and anthocyanin related genes such as F3H. A KEGG analysis suggested that flavonoid biosynthesis and plant hormone signaling transduction pathways were significantly enriched in the upregulated gene list. In particular, among 103 ERF genes, the expression of ERF5 showed the most positive correlation with the anthocyanin change pattern across both genotypes and in the post-flowering stages, with a Pearson correlation coefficient (PCC) of 0.93. Electrophoresis mobility shift assay (EMSA) and luciferase assay suggested that ERF5 binds to the promoter regions of MYBA and F3H and transcriptionally activates their gene expression. We elucidated a potential mechanism by which ethylene enhances anthocyanin accumulation in mulberry fruits and highlighted the importance of the ERF5 gene in controlling the anthocyanin content in mulberry species. This knowledge could be used for engineering purposes in future mulberry breeding programs.
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Jin, Si-Won, Md Abdur Rahim, Hoy-Taek Kim, Jong-In Park, Jong-Goo Kang y Ill-Sup Nou. "Molecular analysis of anthocyanin-related genes in ornamental cabbage". Genome 61, n.º 2 (febrero de 2018): 111–20. http://dx.doi.org/10.1139/gen-2017-0098.
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Ornamental cabbage (Brassica oleracea var. acephala) is a winter-grown and important decorative plant of the family Brassicaceae, which displays an exceptional coloration in the central leaves of the rosette. Anthocyanins are the key determinant of the red, purple, and blue colors of vegetative and reproductive parts of many plant species including ornamental cabbage. Total anthocyanin content was measured spectrophotometrically, and the highest anthocyanin content was detected in the red followed by light-red and white ornamental cabbage lines. Anthocyanin biosynthesis is controlled by members of three different transcription factor (TF) families, such as MYB, basic helix-loop-helix (bHLH), and WD40 repeats (WDR), which function as a MBW complex. We identified three MYB, six bHLH, and one WDR TFs that regulate anthocyanin biosynthesis in ornamental cabbage. The expression of the regulatory and biosynthetic genes for anthocyanin synthesis was determined by qPCR. The tested structural genes of the anthocyanin pathway were shown to be up-regulated in the red followed by light-red ornamental cabbage lines; however, the expression levels of the late biosynthetic genes were barely detected in the white ornamental cabbage lines. Among the regulatory genes, BoPAP2 (MYB), BoTT8, BoEGL3.1, and BoMYC1.2 (bHLH), and BoTTG1 (WDR) were identified as candidates for the regulation of anthocyanin biosynthesis. This work could be useful for the breeding of novel colorful ornamental cabbage cultivars.
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Andrea, Moglia, Elia Florio Francesco, Iacopino Sergio, Guerrieri Alessandra, Anna Milani Maria, Comino Cinzia, Barchi Lorenzo et al. "Identification of a new R3 MYB type repressor and functional characterization of the members of the MBW transcriptional complex involved in anthocyanin biosynthesis in eggplant (S. melongena L.)". PLOS ONE 15, n.º 5 (14 de mayo de 2020): e0232986. http://dx.doi.org/10.1371/journal.pone.0232986.
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Wu, Chang-Hao, Gerrit J. Schut, Farris L. Poole, Dominik K. Haja y Michael W. W. Adams. "Characterization of membrane-bound sulfane reductase: A missing link in the evolution of modern day respiratory complexes". Journal of Biological Chemistry 293, n.º 43 (4 de septiembre de 2018): 16687–96. http://dx.doi.org/10.1074/jbc.ra118.005092.
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Hyperthermophilic archaea contain a hydrogen gas–evolving,respiratory membrane–bound NiFe-hydrogenase (MBH) that is very closely related to the aerobic respiratory complex I. During growth on elemental sulfur (S°), these microorganisms also produce a homologous membrane-bound complex (MBX), which generates H2S. MBX evolutionarily links MBH to complex I, but its catalytic function is unknown. Herein, we show that MBX reduces the sulfane sulfur of polysulfides by using ferredoxin (Fd) as the electron donor, and we rename it membrane-bound sulfane reductase (MBS). Two forms of affinity-tagged MBS were purified from genetically engineered Pyrococcus furiosus (a hyperthermophilic archaea species): the 13-subunit holoenzyme (S-MBS) and a cytoplasmic 4-subunit catalytic subcomplex (C-MBS). S-MBS and C-MBS reduced dimethyl trisulfide (DMTS) with comparable Km (∼490 μm) and Vmax values (12 μmol/min/mg). The MBS catalytic subunit (MbsL), but not that of complex I (NuoD), retains two of four NiFe-coordinating cysteine residues of MBH. However, these cysteine residues were not involved in MBS catalysis because a mutant P. furiosus strain (MbsLC85A/C385A) grew normally with S°. The products of the DMTS reduction and properties of polysulfides indicated that in the physiological reaction, MBS uses Fd (Eo′ = −480 mV) to reduce sulfane sulfur (Eo′ −260 mV) and cleave organic (RSnR, n ≥ 3) and anionic polysulfides (Sn2−, n ≥ 4) but that it does not produce H2S. Based on homology to MBH, MBS also creates an ion gradient for ATP synthesis. This work establishes the electrochemical reaction catalyzed by MBS that is intermediate in the evolution from proton- to quinone-reducing respiratory complexes.
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Mo, Rongli, Na Zhang, Jinxin Li, Qiang Jin, Zhixian Zhu, Zhaoxia Dong, Yong Li, Cheng Zhang y Cui Yu. "Transcriptomic Analysis Provides Insights into Anthocyanin Accumulation in Mulberry Fruits". Horticulturae 8, n.º 10 (7 de octubre de 2022): 920. http://dx.doi.org/10.3390/horticulturae8100920.
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Mulberry fruits are rich in anthocyanins, which are important secondary metabolites that give mulberries their bright color, favorable taste and high nutritional quality, making them a popular fruit. However, few studies have focused on the molecular mechanism underlying anthocyanin accumulation in mulberries and the gene regulatory networks of anthocyanin biosynthetic pathways remain largely unknown. In this study, we performed RNA sequencing to identify differentially expressed genes (DEGs) associated with anthocyanin accumulation between two mulberry genotypes (‘Zi Jing’, ZJ and ‘Zhen Zhu Bai’, ZZB, with purple and white fruit flesh, respectively) at 5, 18, 27 and 31 days after flower. Using transcriptome analysis, we explored several key DEGs involved in the anthocyanin biosynthetic pathway, including the structural genes: CHS, CHI, F3H, DFR1, DFR2 and ANS, known as MBW complex genes: MYB (M.alba_G0017209), MYB (M.alba_G0017689), bHLH (M.alba_G0012659), bHLH (M.alba_G0009347) and bHLH3 (M.alba_G0016257) and the ethylene response factor: ERF (M.alba_G0016603). Of these, changing trends related to expression pattern and anthocyanin content showed their most positive correlation at the post-flowering stage in both genotypes. Our results indicated that ethylene enhances anthocyanin accumulation in mulberry fruits. Furthermore, qRT-PCR was performed to confirm the above-mentioned genes’ expression (except for MYB (M.alba_G0017689) and bHLH (M.alba_G0009347) was significantly up-regulated under ethylene treatment at 300 mg/L. These findings help uncover the gene regulatory networks of the anthocyanin biosynthetic pathway and will contribute to engineering purposes in future mulberry breeding programs.
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Beljic-Ivanovic, Katarina y Nevenka Teodorovic. "Morphological characteristics of mesiobuccal root canals of the first maxillary molars". Srpski arhiv za celokupno lekarstvo 138, n.º 7-8 (2010): 414–19. http://dx.doi.org/10.2298/sarh1008414b.
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Introduction. The first maxillary molar is a tooth with three roots, and mesiobuccal one is with the most complex canal morphology. Factors influencing variations of its morphology are numerous, and may significantly complicate endodontic treatment. Objective. The objective was to investigate the number, configuration and curvature orientation of the mesiobuccal root canals in the maxillary first molars. Methods. The study was conducted on 200 mesiobuccal (MB) roots of extracted first molars in human subjects using radiography. In each canal Flexofile was introduced until reaching the apical foramen and the root was then radiographed in series from two projections. Number of root canals (MB1, MB2 and MB3), configuration according to Vertucci classification, and the orientation of the curvature were established. Relevant statistical parameters and the significance of differences were computed (p<0.05). Results. Of total 200 mesiobuccal roots 86.5% were with two, 9% with three, and 4.5% with a single canal. Most frequent configurations were type IV (36%) and II (34.5%). From the clinical projection all MB1 canals were oriented distally, from the proximal 78% palatally and 22% buccally. The orientation of all MB2 canals was distal from the clinical projection, from the proximal projection 76% were oriented palatally, and 24% buccally. The MB3 canal was always oriented distally from the clinical projection, and buccally from the proximal aspect. Conclusion. The mesiobuccal roots of the first maxillary molars showed multiple canals in 96%, with dominant Vertucci type II and IV of configuration. All canals were curved.
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Begum, Najma, Noreen Duddy, Oana Sandu, Jennifer Reinzie y Louis Ragolia. "Regulation of Myosin-Bound Protein Phosphatase by Insulin in Vascular Smooth Muscle Cells: Evaluation of the Role of Rho Kinase and Phosphatidylinositol-3-Kinase-Dependent Signaling Pathways". Molecular Endocrinology 14, n.º 9 (1 de septiembre de 2000): 1365–76. http://dx.doi.org/10.1210/mend.14.9.0522.
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Abstract In this study, we examined the molecular mechanism of myosin-bound protein phosphatase (MBP) regulation by insulin and evaluated the role of MBP in insulin-mediated vasorelaxation. Insulin rapidly stimulated MBP in confluent primary vascular smooth muscle cell (VSMC) cultures. In contrast, VSMCs isolated from diabetic and hypertensive rats exhibited impaired MBP activation by insulin. Insulin-mediated MBP activation was accompanied by a rapid time-dependent reduction in the phosphorylation state of the myosin-bound regulatory subunit (MBS) of MBP. The decrease observed in MBS phosphorylation was due to insulin-induced inhibition of Rho kinase activity. Insulin also prevented a thrombin-mediated increase in Rho kinase activation and abolished the thrombin-induced increase in MBS phosphorylation and MBP inactivation. These data are consistent with the notion that insulin inactivates Rho kinase and decreases MBS phosphorylation to activate MBP in VSMCs. Furthermore, treatment with synthetic inhibitors of phosphatidylinositol-3 kinase (PI3kinase), nitric oxide synthase (NOS), and cyclic guanosine monophosphate (cGMP) all blocked insulin’s effect on MBP activation. We conclude that insulin stimulates MBP via its regulatory subunit, MBS partly by inactivating Rho kinase and stimulating NO/cGMP signaling via PI3-kinase as part of a complex signaling network that controls 20-kDa myosin light chain (MLC20) phosphorylation and VSMC contraction.
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Li, Chengshuai, Lijing Zhang, Decao Niu, Shuzhen Nan, Xiumei Miao, Xiaowei Hu y Hua Fu. "Investigation of flavonoid expression and metabolite content patterns during seed formation of Artemisia sphaerocephala Krasch." Seed Science Research 31, n.º 2 (junio de 2021): 136–48. http://dx.doi.org/10.1017/s096025852100012x.
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AbstractFlavonoids are a group of phenolic secondary metabolites in plants that have important physiological, ecological and economic value. In this study, using the desert plant Artemisia sphaerocephala Krasch. as the sample material, the content and components of the total flavonoids in its seeds at seven different developmental stages were determined. In addition, the genes involved in flavonoid metabolism were identified by full-length transcriptome sequencing (third-generation sequencing technology based on PacBio RS II). Their expression levels were analysed by RNA-seq short reading sequencing, to reveal the patterns and regulation mechanisms of flavonoid accumulation during seed development. The key results were as follows: the content of total flavonoids in mature seeds was 15.05 mg g−1, including five subclasses: flavonols, chalcones, flavones, flavanones and proanthocyanidins, among which flavonols accounted for 45.78%. The period of rapid accumulation of flavonoids was 40–70 d following anthesis. The high expression of phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase (4CL) and UDP-glucose:flavonoids 3-o-glucosyltransferase (UF3GT) promoted the accumulation of total flavonoids, while the high expression of flavonoids 3′-hydroxylase (F3′H) and flavonols synthase (FLS) made flavanols the main component. Transcription factors such as the MYB-bHLH-WDR (MBW) complex and Selenium-binding protein (SBP) directly regulated the structural genes of flavonoid metabolism, while C2H2-type zinc finger (C2H2), Zinc-finger transcription factor (GATA), Dehydration-responsive element binding (DREB), Global Transcription factor Group E protein (GTE), Trihelix DNA-binding factors (Trihelix) and Phytochrome-interacting factor (PIF) indirectly promoted the synthesis of flavonoids through hormones such as brassinoidsteroids (BRs) and abscisic acid (ABA). These results provided valuable resources for the application of related genes in genetics and breeding.
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Zhang, Yanjie, Tianjiao Zhang, Qing Zhao, Xiaodong Xie, Yan Li, Qiyan Chen, Fang Cheng, Jianwei Tian, Huihui Gu y Jinyong Huang. "Comparative Transcriptome Analysis of the Accumulation of Anthocyanins Revealed the Underlying Metabolic and Molecular Mechanisms of Purple Pod Coloration in Okra (Abelmoschus esculentus L.)". Foods 10, n.º 9 (14 de septiembre de 2021): 2180. http://dx.doi.org/10.3390/foods10092180.
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Color is an essential agronomic trait and the consumption of high anthocyanin containing vegetables in daily diet does provide benefits to human health, but the mechanisms on anthocyanin accumulation in tender pods of okra (Abelmoschus esculentus L.) were totally unknown. In this study, a wide characterization and quantitation of anthocyanins and flavonols in tender pods of 15 okra varieties were performed by UHPLC-Q-Orbitrap HRMS for the first time. Two major anthocyanins (delphinidin 3-O-sambubioside and cyanidin 3-O-sambubioside) and six kinds of flavonol glycosides (most are quercetin-based) were identified and quantified. The coloration of the purple okra pod mainly arises from the accumulation of both delphinidin 3-O-sambubioside and cyanidin 3-O-sambubioside in most of purple varieties (Hong Yu, Bowling Red and Burgundy), except Jing Orange. The significant differences in the compositions and contents of anthocyanins are responsible for the pod color ranging from brick-red to purplish-red among the various okra cultivars. Furthermore, four representative okra cultivars exhibiting obvious differences in anthocyanin accumulation were further analyzed with transcriptome and more than 4000 conserved differentially expressed genes were identified across the three compared groups (B vs. BR, B vs. HY and B vs. JO). Based on the comprehensive analysis of transcriptomic data, it was indicated that MBW complex consisting of AeMYB114, AeTT8, and AeTTG1 and other transcriptional factors coordinately regulate the accumulation of anthocyanins via the transcriptional regulation of structural genes. Moreover, four independent working models explaining the diversities of anthocyanin pigmentation in okra pods were also proposed. Altogether, these results improved our understanding on anthocyanin accumulation in okra pods, and provided strong supports for the development of okra pod as a functional food in the future.
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Song, Hayoung, Jong-In Park, Byung-Ho Hwang, Hankuil Yi, HyeRan Kim y Yoonkang Hur. "SNP in DFR1 Coding Sequence Is Tightly Associated with Anthocyanin Accumulation in Cabbage (B. oleracea var. capitata f. alba) at Low Temperature". Agronomy 10, n.º 4 (23 de abril de 2020): 602. http://dx.doi.org/10.3390/agronomy10040602.
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Keeping green leaf color at the time of harvest is one of the important traits for breeding of Brassica oleracea var. capitata f. alba, and this trait is related to low anthocyanin contents. To understand the differential accumulation of anthocyanins in cabbage, we selected high anthocyanin accumulators (HAAs) and low anthocyanin accumulator (LAAs) of cabbages and examined the anthocyanin content and the expression of anthocyanin biosynthesis-related genes. Among many genes investigated, BoDFR1 was found to be closely related to anthocyanin accumulation, even under low temperature (LT) conditions. BoDFR1 sequence analyses between HAAs and LAAs revealed that there is a single nucleotide polymorphism (SNP) (1118T/A) in the coding sequence, which substitutes one amino acid from Leu261 to His261; we named BoDFR1 with His261 substitution as BoDFR1v. This amino acid substitution did not affect dihydroflavonol 4-reductase (DFR) activity and substrate specificity, but the polymorphism showed tight association to the BoDFR1 expression, i.e., high level expression of BoDFR1 and low level expression of BoDFR1v under LT conditions. The high levels of BoDFR1 expression were due to the high levels of BoMYB114 and BobHLH expressions combined with low level expression of BoMYBL2, a repressor MYB. On the other hand, low levels of BoDFR1v expression seemed to be related to very low level expressions of BoMYB114 and BobHLH combined with a high level expression of BoMYBL2. It seems that different expression levels of these regulatory genes for MBW (MYB-bHLH-WD40) complex between HAAs and LAAs regulate BoDFR expression and anthocyanin accumulation. Using a single nucleotide polymorphism (SNP) between BoDFR1 and BoDFR1v, molecular markers for PCR and high resolution melt analyses were developed and validated to distinguish between HAAs and LAAs. Combined use of the BoDFR1 SNP marker with other stress markers, such as a cold tolerant marker, will greatly improve cabbage breeding.
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TAN, Suet Mien, Maxey C. M. CHUNG, Oi Lian KON, Steffen THIEL, Szu Hee LEE y Jinhua LU. "Improvements on the purification of mannan-binding lectin and demonstration of its Ca2+-independent association with a C1s-like serine protease". Biochemical Journal 319, n.º 2 (15 de octubre de 1996): 329–32. http://dx.doi.org/10.1042/bj3190329.
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Mannan-binding lectin (MBL), previously called ‘mannan-binding protein’ or MBP, is a plasma C-type lectin which, upon binding to carbohydrate structures on micro-organisms, activates the classical pathway of complement. Purification of MBL relies on its Ca2+-dependent affinity for carbohydrate, but existing methods are susceptible to contamination by anti-carbohydrate antibodies. In the present study a sequential-sugar-elution method has been developed which can achieve a preparation of virtually pure MBL and its associated serine protease (MBL-associated serine protease, MASP) by two steps of affinity chromatography. In further separation of MASP from MBL, it was found that activated MASP was associated with MBL independent of Ca2+. Since MBL was found to bind to underivatized Sepharose 4B, the MBL-MASP complex was purified using Sepharose 4B and protease inhibitors were included to purify the complex with MASP in its proenzyme form. Analysis of thus-purified MBL-MASP complex by gel filtration on a Sephacryl S-300 column at pH 7.8 showed that the proenzyme MASP was also associated with MBL independently of Ca2+, but that the complex could be disrupted at a low pH (5.0). Therefore the mechanism of MBL-MASP-mediated complement activation appears to be significantly different from the C1-mediated classical pathway.
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Bai, Zhiqiang, Xiaowen Sun, Xun Yu y Lin Li. "Chitosan Microbeads as Supporter for Pseudomonas putida with Surface Displayed Laccases for Decolorization of Synthetic Dyes". Applied Sciences 9, n.º 1 (3 de enero de 2019): 138. http://dx.doi.org/10.3390/app9010138.
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Various untreated wastewaters contaminated with industrial dyes pose significant pollution hazards to the natural environment as well as serious risks to public health. The current study reports a new material with a configurative chitosan matrix and engineered Pseudomonas putida cells with surface-displayed laccases that can decolorize five industrial dyes. Through a self-configuring device, five chitosan microbeads (CTS-MBs) with different particle sizes were prepared. P. putida cells were then immobilized onto the CTS-MBs under optimized immobilization conditions, forming a degrading-biosorbent dual-function decolorization complex. Scanning electron microscope and infrared analysis confirmed the successful immobilization of the cells onto the CTS-MB matrix. The optimized CTS-MB1 with surface-grafted aldehyde groups (aCTS-MB1) complex was capable of decolorizing Acid Green 25 and Acid Red 18 over a pH range of 2.5–8.5 and a relatively broad temperature range of 15–85 °C, with a maximum relative decolorization value of over 94%; the complex was also able to efficiently decolorize Direct Red 243, Reactive Blue 220 and Reactive Blue 198. Moreover, the aCTS-MB1 composite showed favorable activity in continuous and regenerative decolorization reactions. Therefore, the chitosan-immobilized decolorizing material, with both improved mechanical strength and performance, shows potential for further large-scale or continuous processes.
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Zhang, Yiyi, Tinghong Zhou, Zhongwu Dai, Xiaoyu Dai, Wei Li, Mengxia Cao, Chengru Li et al. "Comparative Transcriptomics Provides Insight into Floral Color Polymorphism in a Pleione limprichtii Orchid Population". International Journal of Molecular Sciences 21, n.º 1 (30 de diciembre de 2019): 247. http://dx.doi.org/10.3390/ijms21010247.
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Floral color polymorphism can provide great insight into species evolution from a genetic and ecological standpoint. Color variations between species are often mediated by pollinators and are fixed characteristics, indicating their relevance to adaptive evolution, especially between plants within a single population or between similar species. The orchid genus Pleione has a wide variety of flower colors, from violet, rose-purple, pink, to white, but their color formation and its evolutionary mechanism are unclear. Here, we selected the P. limprichtii population in Huanglong, Sichuan Province, China, which displayed three color variations: Rose-purple, pink, and white, providing ideal material for exploring color variations with regard to species evolution. We investigated the distribution pattern of the different color morphs. The ratio of rose-purple:pink:white-flowered individuals was close to 6:3:1. We inferred that the distribution pattern may serve as a reproductive strategy to maintain the population size. Metabolome analysis was used to reveal that cyanindin derivatives and delphidin are the main color pigments involved. RNA sequencing was used to characterize anthocyanin biosynthetic pathway-related genes and reveal different color formation pathways and transcription factors in order to identify differentially-expressed genes and explore their relationship with color formation. In addition, qRT-PCR was used to validate the expression patterns of some of the genes. The results show that PlFLS serves as a crucial gene that contributes to white color formation and that PlANS and PlUFGT are related to the accumulation of anthocyanin which is responsible for color intensity, especially in pigmented flowers. Phylogenetic and co-expression analyses also identified a R2R3-MYB gene PlMYB10, which is predicted to combine with PlbHLH20 or PlbHLH26 along with PlWD40-1 to form an MBW protein complex (MYB, bHLH, and WDR) that regulates PlFLS expression and may serve as a repressor of anthocyanin accumulation-controlled color variations. Our results not only explain the molecular mechanism of color variation in P. limprichtii, but also contribute to the exploration of a flower color evolutionary model in Pleione, as well as other flowering plants.
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Fritz, R. B., M. J. Skeen, C. H. Chou, M. Garcia y I. K. Egorov. "Major histocompatibility complex-linked control of the murine immune response to myelin basic protein." Journal of Immunology 134, n.º 4 (1 de abril de 1985): 2328–32. http://dx.doi.org/10.4049/jimmunol.134.4.2328.
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Abstract Recent experiments have shown that different regions of myelin basic protein (MBP) are encephalitogenic for different inbred strains of mice. It was therefore of interest to determine whether the immune response to MBP was MHC associated, and if so, what subregion controlled this response. Because PL/J and A/J mice were good responders to mouse MBP and C57Bl/10SN were not, B10.PL(73NS) and B10.A mice were immunized with mouse MBP under conditions designed to induce EAE. These strains were found to be highly susceptible. Intra-H-2 recombinant mice were then assessed for susceptibility. B10.A(4R) and B10.MBR were susceptible, whereas B10.A(5R) were resistant. Thus, EAE induced by purified MBP is under the control of the MHC, and the response maps to the I-A subregion. Production of IL 2 in vitro by T cells from MBP-primed mice in the presence of antigen and adherent cells was blocked by monoclonal antibody to the I-A, but not the I-E, subregion. When the specificity of the encephalitogenic response was tested, peptide 1-37 was active in B10.PL(73NS) and B10.A mice, whereas peptide 89-169 was active in A.SW, SWR, and B10.T(6R) strains. Serum from mice immunized with MBP peptides was assayed for antibody content. PL, B10.PL, and B10.A mice made a good antibody response to peptides 1-37 and 43-88 but were nonresponsive to peptide 89-169. SJL, A.SW, SWR, and B10.T(6R) mice responded well to peptide 89-169 but were poorly responsive to peptides 1-37 and 43-88.
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Sunstrum, Frederick G., Hannah L. Liu, Sharon Jancsik, Lufiani L. Madilao, Joerg Bohlmann y Sandra Irmisch. "4-Coumaroyl-CoA ligases in the biosynthesis of the anti-diabetic metabolite montbretin A". PLOS ONE 16, n.º 10 (7 de octubre de 2021): e0257478. http://dx.doi.org/10.1371/journal.pone.0257478.
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Background Montbretins are rare specialized metabolites found in montbretia (Crocosmia x crocosmiiflora) corms. Montbretin A (MbA) is of particular interest as a novel therapeutic for type-2 diabetes and obesity. There is no scalable production system for this complex acylated flavonol glycoside. MbA biosynthesis has been reconstructed in Nicotiana benthamiana using montbretia genes for the assembly of MbA from its various different building blocks. However, in addition to smaller amounts of MbA, the therapeutically inactive montbretin B (MbB) was the major product of this metabolic engineering effort. MbA and MbB differ in a single hydroxyl group of their acyl side chains, which are derived from caffeoyl-CoA and coumaroyl-CoA, respectively. Biosynthesis of both MbA and MbB also require coumaroyl-CoA for the formation of the myricetin core. Caffeoyl-CoA and coumaroyl-CoA are formed in the central phenylpropanoid pathway by acyl activating enzymes (AAEs) known as 4-coumaroyl-CoA ligases (4CLs). Here we investigated a small family of montbretia AAEs and 4CLs, and their possible contribution to montbretin biosynthesis. Results Transcriptome analysis for gene expression patterns related to montbretin biosynthesis identified eight different montbretia AAEs belonging to four different clades. Enzyme characterization identified 4CL activity for two clade IV members, Cc4CL1 and Cc4CL2, converting different hydroxycinnamic acids into the corresponding CoA thioesters. Both enzymes preferred coumaric acid over caffeic acid as a substrate in vitro. While expression of montbretia AAEs did not enhance MbA biosynthesis in N. benthamiana, we demonstrated that both Cc4CLs can be used to activate coumaric and caffeic acid towards flavanone biosynthesis in yeast (Saccharomyces cerevisiae). Conclusions Montbretia expresses two functional 4CLs, but neither of them is specific for the formation of caffeoyl-CoA. Based on differential expression analysis and phylogeny Cc4CL1 is most likely involved in MbA biosynthesis, while Cc4CL2 may contribute to lignin biosynthesis. Both Cc4CLs can be used for flavanone production to support metabolic engineering of MbA in yeast.
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Sun, H., K. Dunham, L. Cunningham, Y. Ni, M. Westover y R. Thomas. "0348 Sleep EEG-Based Brain Age Index is Reduced Under Continuous Positive Airway Pressure Treatment". Sleep 43, Supplement_1 (abril de 2020): A132. http://dx.doi.org/10.1093/sleep/zsaa056.345.
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Abstract Introduction Continuous positive airway pressure (CPAP) is a treatment for apnea. With long-term CPAP, changes in electroencephalogram (EEG) include increased delta power (1 - 4Hz) and sigma power (11 - 15Hz, spindle). However, the short-term EEG response to CPAP in a split-night study is less quantified. We recently developed a “brain age” model using sleep EEG features. The brain age index (BAI) is defined as the difference between chronological age and brain age (BA - CA). Here we first quantify how BAI changes during CPAP in the same patient, and then investigate how much brain age features during the diagnostic part can predict the reduction in apnea-hypopnea index (AHI) during CPAP. Methods The dataset consisted of 160 subjects. The average age was 59 years with 53% male, 24% female and 23% unknown. We extracted 480 features including band powers, and then computed the BAIs for both diagnostic and CPAP parts. To predict the reduction in AHI during CPAP, we fit a Bayesian regression model using the brain age features, demographics, and sleep parameters during the diagnostic part, and assessed the feature importance using dominance analysis. Results The BAI from the diagnostic part is significantly reduced compared to BAI during CPAP for the same subject (paired t-test, p < 0.01). The diagnostic part has an average BAI 2.24 years; and the CPAP part -4.75 years. The brain age features that are increased during CPAP include sigma powers in N2 and N3. The prediction of AHI reduction has Pearson’s correlation 0.85. The features predictive of reduced AHI are the diagnostic AHI (explained variance 69%), followed by high/low waveforms during N2 (e.g. K-complex, measured by kurtosis) (8.6%), delta power during REM (4.5%) and N1 (2%). The feature predictive of increased AHI is frontal alpha power during quiet awake (2.6%). Conclusion The average BAI is reduced during CPAP. BAI provides a novel view of the acute response to CPAP in sleep EEG. Future study with more CPAP failure patients has the potential of predicting CPAP failure. Support MBW is supported by Glenn Foundation for Medical Research. RJT is supported by Category I AASM Foundation.
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Wang, Yu, En Chen, Jun Qing Gao y Yun Feng Gong. "Joint Modeling and Simulation of the Spindle System of Hammer Crusher Based on Finite Element Analysis and Flexible Multi-Body Dynamics. Part2: Analysis". Advanced Materials Research 630 (diciembre de 2012): 297–301. http://dx.doi.org/10.4028/www.scientific.net/amr.630.297.
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The hammer crusher always works under heavy load, discontinuous and impact working condition, which is complex, especially when impact happens. The spindle is one of the most important parts of the hammer crusher, the performance of which has a great effect on the whole structure. This paper discussed the main loads acting on the spindle. After the multi-body system dynamics (MBD) models were built up in previous paper, three kinds of multi-body system simulation (MBS) analysis were conducted to gain the impact loads, then a static analysis of spindle was carried out with the loads, which verified the reliability of the design of the spindle. To evaluate the correctness of the MBS results, comparisons between simulation and theoretical impact force results were done, which proved the acceptance of the MBD models. Another theoretical analysis model for the spindle was established and employed to verify the results of FEA and reliability of the design of the spindle.
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Chernyak, A. V., G. V. Neklyudova, S. A. Krasovskiy, K. Yu Mikhaylichenko, Zh K. Naumenko y G. E. Polivanov. "Nitrogen leaching in multiple breathing and structural changes in the bronchopulmonary system in adult patients with cystic fibrosis". Russian Pulmonology 30, n.º 2 (21 de junio de 2020): 193–203. http://dx.doi.org/10.18093/0869-0189-2020-30-2-193-203.
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The aim of this work was to assess the functional and structural disorders of the bronchopulmonary system detected by high-resolution computed tomography (HRCT) in adult patients with cystic fibrosis (CF), and to determine the correlation between them.Methods. A cross-sectional study included patients with CF (n = 54: 20 male and 34 female; median age 25 years) and healthy volunteers (n = 32: 12 male, 20 female; median age 25 years). A complex study of the pulmonary function test (PFT) was carried out; it included spirometry, bodyplethysmography and measurement of the diffusing lung capacity for carbon monoxide (DLCO), nitrogen leaching in multiple respiration (NLMR) and HRCT. Dyspnea was assessed using the Modified Research Council Scale (mMRC). NLMR measurements were performed using the Easy-One Pro module, MBW (NDD Medizintechnik AG, Switzerland). Analysis of HRCT data according to the Bhalla classification was performed by two independent, experienced radiologists.Results. The mean value (± SD) of the forced expiratory volume for 1 second (FEV1) was 63 ± 26% of the proper value, forced vital capacity of the lungs (FVC) was 86 ± 20% of the proper value, the ratio of FEV1/FVC was 61 ± 15%; residual lung volume (RLV) was 220 ± 71% of the proper value, the ratio of RLV/ total lung capacity (TLC) was 48 ± 13%, intrathoracic gas volume was 150 ± 33% of the proper value, DLCO was 80 ± 16% of the proper value, lung clearance index (LCI) was 16.9 ± 5.0; moment ratio (MR2) was 54.7 ± 34.1. Bronchoectases with predominant lesions of > 9 segments and bronchial lesions from V generation and more distal were found in all patients. Peribronchial infiltration and mucoid plugs were also diagnosed in almost all patients (94 and 96%, respectively), while bronchogenic cysts or abscesses, atelectasis/consolidation, bullae or emphysema were rarely detected (in 30, 35, 20, and 17% of cases, respectively). The parameters of NLMR were statistically significantly correlated with both the PFT parameters and the HRTC data.Conclusion. In adult patients with CF, there is a significant unevenness of pulmonary ventilation, progressing as structural damage to the bronchopulmonary system increases and the PFT worsens. With a statistically significant increase in MR, the involvement of not only the central, but also peripheral airways in the pathological process is emphasized. It has been established that in adult CF patients there is a strong correlation between LCI and the severity of structural changes, detected by HRCT, comparable in strength and significance to FEV1.
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Kavas, Musa, Mohamed Farah Abdulla, Karam Mostafa, Zafer Seçgin, Bayram Ali Yerlikaya, Çiğdem Otur, Gökhan Gökdemir, Aslıhan Kurt Kızıldoğan, Jameel Mohammed Al-Khayri y Shri Mohan Jain. "Investigation and Expression Analysis of R2R3-MYBs and Anthocyanin Biosynthesis-Related Genes during Seed Color Development of Common Bean (Phaseolus vulgaris)". Plants 11, n.º 23 (5 de diciembre de 2022): 3386. http://dx.doi.org/10.3390/plants11233386.
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Anthocyanins are responsible for the coloration of common bean seeds, and their accumulation is positively correlated with the expression level of anthocyanin biosynthetic genes. The MBW (MYB-bHLH-WD40) complex is thought to regulate the expression of these genes, and MYB proteins, which are a key factor in activating anthocyanin pathway genes, have been identified in several plants. This study demonstrated gene structures, chromosomal placements, gene duplications of R2R3-MYBs, miRNAs associated with R2R3-MYBs, and the interaction of these genes with other flavonoid regulatory genes. qRT-PCR was used to investigate the role of specific R2R3-MYBs and flavonoid genes in common bean seed color development. As a result of a comprehensive analysis with the help of in silico tools, we identified 160 R2R3-MYB genes in the common bean genome. We divided these genes into 16 classes on the basis of their intron-exon and motif structures. Except for three, the rest of the common bean R2R3-MYB members were distributed to all chromosomes with different densities, primarily located on chromosomes 3 and 8. We identified a total of 44 duplicated gene pairs dispersed across 11 chromosomes and evolved under purifying selection (Ka/Ks < 1), 19 of which were derived from a whole-genome duplication. Our research uncovered 25 putative repressor PvMYB proteins that contain the EAR motif. Additionally, fifty different cis-regulatory elements regulated by light, stress, and hormone were identified. Within the genome of the common bean, we discovered a total of 36 microRNAs that target a total of 72 R2R3-MYB transcripts. The effect of 16 R2R3-MYB genes and 16 phenylpropanoid pathway genes, selected on the basis of their interaction in the protein-protein interaction map, playing role in the regulation of seed coat color development was evaluated using qRT-PCR in 5 different tissues at different developmental stages. The results revealed that these specific genes have different expression levels during different developmental periods, with higher levels in the pod filling and early pod stages than in the rest of the developmental periods. Furthermore, it was shown that PvTT8 (bHLH), PvTT2 (PvMYB42), PvMYB113, PvTTG1, and PvWD68 genes have effects on the regulation of seed coat color. The findings of this study, which is the first to use whole-genome analysis to identify and characterize the R2R3-MYB genes in common bean, may serve as a reference for future functional research in the legume.
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Geraybeyli, S. A. "RECYCLING SLAG FROM COMBUSTION OF MSW INTO COMPLEX MINERAL FERTILIZERS USING POOR PHOSPHORITE". Chemical Problems 20, n.º 2 (2022): 138–44. http://dx.doi.org/10.32737/2221-8688-2022-2-138-144.
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The article deals with the issue of secondary recycling municipal solid waste (MSW) into complex mineral fertilizers using domestic agricultural raw materials. Used in the recycling were slag from combustion of MSW and poor phosphorite. The nature of the decomposition of phosphorite 50-80% acid H2SO4 was studied at an acid consumption rate of 60-110%, of the consumption rate of acid H2SO4, which made it possible to identify optimal conditions used also for recycling binary raw materials. The increase in the content of assimilable Р2О5 has been uncovered in the liquid phase during the recycling binary raw materials in comparison with the decomposition of phosphorite under similar conditions. The role of MSW of slag in increasing the content of assimilable Р2О5 due to the improvement of conditions for the diffusion of molecules of the formed phosphoric acid to phosphorite particles is explained. The possibility of regulating the characteristics of the obtained complex mineral fertilizers by the ratio of the components of raw materials is shown.
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Długosz, Jacek, Anna Piotrowska-Długosz, Anetta Siwik-Ziomek y Anna Figas. "Depth-Related Changes in Soil P-Acquiring Enzyme Activities and Microbial Biomass—The Effect of Agricultural Land Use/Plant Cover and Pedogenic Processes". Agriculture 12, n.º 12 (3 de diciembre de 2022): 2079. http://dx.doi.org/10.3390/agriculture12122079.
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Although the phosphatase enzymes regulate phosphorus (P) turnover throughout the soil profile, at present, they are rarely studied and are less well understood in the deeper soil layers than in the surface horizons. Hence the changes in P-associated soil properties were assessed throughout five Phaeozem profiles for different agricultural land uses including alfalfa, winter wheat, grapevine, apple trees and hops. The acid phosphatase (AcP), alkaline phosphatase (AlP) and phosphodiesterase (PDE) activity was assayed, as were the microbial biomass carbon (MBC) and phosphorus (MBP) contents and also other properties (e.g., available phosphorus, total organic carbon, total nitrogen). We have also determined the mass, length and surface area of the plant roots. In general, the activities of the studied enzymes were highest in the topsoil in four out of the five profiles studied, which corresponded to the highest level of root mass. The older the plant, the greater the root mass and increased enzymatic activity in the deeper horizons of apple trees and hop profiles in comparison to the surface layers. The greatest enzymatic activity, MBC and MBP contents were found in the horizons with a TOC content >0.5% and decreased down the soil profiles similarly to the changes in TOC and TN contents. While the studied properties were determined to varying degrees by means of the organic C content and availability in all of the genetic horizons, the influence of the prevailing conditions and the factors related to soil depth and pedogenic processes were less pronounced. The clay content was related to a significant extent to all of the studied enzyme activities, but only in horizons with a TOC content <0.5%. Significantly higher phosphatase activity under aerobic as opposed to anaerobic conditions were determined in this study, while the opposite trend was found for the content of MBC and MBP as well as the ratio of MBC/MBP. Overall, we pointed out the complex effect of the soil depth, soil forming-processes and cultivated plants on soil P-associated enzyme activities and other properties throughout the soil profiles. This knowledge will allow better understanding of the state of enzymes and their contribution to the biogeochemical cycle of soil P, especially in subsoils, where the enzyme activities follow different patterns than those in the surface horizons.
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Girg, Petr y Lukáš Kotrla. "Generalized trigonometric functions in complex domain". Mathematica Bohemica 140, n.º 2 (2015): 223–39. http://dx.doi.org/10.21136/mb.2015.144328.
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Heinze, Stefanie, Michael Hemkemeyer, Sanja Annabell Schwalb, Khalid Saifullah Khan, Rainer Georg Joergensen y Florian Wichern. "Microbial Biomass Sulphur—An Important Yet Understudied Pool in Soil". Agronomy 11, n.º 8 (12 de agosto de 2021): 1606. http://dx.doi.org/10.3390/agronomy11081606.
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Soil microorganisms require a range of essential elements for their optimal functioning and store several elements in the microbial biomass (MB), such as carbon (C), nitrogen (N), phosphorus (P) and sulphur (S), as well as other secondary and trace elements. The C, N and P content of the microbial biomass has been quantified in many studies for many years, whereas S has been the focus only in a few studies, despite the availability of methods and the relevance of MBS for the S turnover in soils. To illustrate the relevance of MBS, this review aims at summarizing the current state of knowledge on the quantities of MBS in different soils, influencing environmental and agricultural management factors, methodological shortcomings, and prospects for soil microbial biomass research. Median MBS contents were 6.0 µg g−1 soil in arable, 7.6 µg g−1 soil in grassland, and 5.7 µg g−1 soil in forest soils. All extractants used led to similar MBS contents in soils with similar soil organic (SO) C contents. MBC and soil pH positively explained MBS, using multiple linear regression analysis. Median MB-C/S ratios increased in the order arable (55), grassland (85), and forest (135) soils. As the overall quantity of MBS data is still small, future studies are required to verify these observations. Moreover, future research needs to more strongly consider stoichiometric relationships of elements in the soil and the soil microbial ionome. The role of S and its complex relationship with the availability of other elements in soils for the soil microbial biomass and its functions remains to be elucidated.
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Mészáros, István. "Complex Magnetic Investigation of Ferritic Stainless Steel". Materials Science Forum 473-474 (enero de 2005): 231–36. http://dx.doi.org/10.4028/www.scientific.net/msf.473-474.231.
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Magnetic Barkhausen noise measurement (MBN) is a relatively new non-destructive detection technique. Its working principle is based on Barkhausen discontinuities or noise when a ferromagnetic material is subjected to a varying magnetic field. MBN is being used to characterise the stress state of a ferritic stainless steel (AISI 430). Other magnetic parameters such as saturation induction (BMax), remnant induction (BR), coercive field (HC) and maximal relative permeability (PMax) derived from the hysteresis loop have also been used to support the results achieved using MBN. Microstructural changes due to cold working and heat treatments were characterized by the applied magnetic measurements. The MBN technique was proved to be a useful non-destructive and quantitative method for microstuctural investigation of the investigated ferritic stainless steel.
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Carvalho, Manuela C., Anabela G. Rodrigues, Luísa M. Conceição, Miguel L. Galvão y Luis C. Ribeiro. "Prothrombin complex concentrate (Octaplex)". Blood Coagulation & Fibrinolysis 23, n.º 3 (abril de 2012): 222–28. http://dx.doi.org/10.1097/mbc.0b013e328351250f.
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&NA;. "Prothrombin complex concentrate (Octaplex)". Blood Coagulation & Fibrinolysis 24, n.º 2 (marzo de 2013): 220. http://dx.doi.org/10.1097/mbc.0b013e32835effca.
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McCann, Malachy, Majella Geraghty, Michael Devereux, Denis O'Shea, James Mason y Luzveminda O'Sullivan. "Insights Into the Mode of Action of the Anti-Candida Activity of 1,10-Phenanthroline and its Metal Chelates". Metal-Based Drugs 7, n.º 4 (1 de enero de 2000): 185–93. http://dx.doi.org/10.1155/mbd.2000.185.
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Metal complexes of malonie acid (metal = Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Ag(I)) were prepared and only the Ag(I) complex inhibited the growth of Candida albicans. Malonate complexes incorporating the chelating 1,10-phenanthroline (1,10-phen) ligand showed a range of activities: good (Mn(II), Cu(II), Ag(I)); moderate (Zn(II)); poor (Co(II), Ni(II)). Metal-free 1,10-phen and Ag(CH3CO2) were also highly active. The metal-free non-chelating ligands 1,7- phenanthroline and 4,7-phenanthroline were inactive and the Cu(II), Mn(II) and Zn(II) complexs of 1,7-phen displayed only marginal activity. Whereas the Cu(II) malonate/1,10-phen complex induces significant cellular oxidative stress the Zn(II) analogue does not.
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Bozovic, Ivan y J. N. Eckstein. "Analysis of Growing Films of Complex Oxides by RHEED". MRS Bulletin 20, n.º 5 (mayo de 1995): 32–38. http://dx.doi.org/10.1557/s0883769400044870.
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The majority of sophisticated ultra-high-vacuum (UHV) systems for deposition of thin films, such as molecular beam epitaxy (MBE) machines, contain some kind of electron diffraction apparatus which is used to scrutinize the surface structure of the film while it is grown. Reflection high energy electron diffraction (RHEED) is probably the most frequently employed configuration. An excellent introduction to RHEED, including a treatment of electron diffraction, reciprocal-space description, reflection from imperfect surfaces, etc., was recently published in the MRS Bulletin by Lagally and Savage. Hence, we will not review these basics here. Rather, we will assume the reader to be familiar with that article, and will refer to it as LS.The materials discussed in LS include Si, Ge on Si, and GaAs. The applications of MBE for synthesis of semiconductor thin films and heterostructures are widely recognized. MRS has recently bestowed its greatest honor, the Von Hippel Award, to Alfred Y. Cho for his pioneering work on MBE synthesis of GaAs and its application to new devices.In contrast, here we focus on complex oxides—cuprates, titanates, manganates, etc. This is a relatively new area of application for both MBE and RHEED. Actually, it was only after the discovery of high-temperature superconductivity (HTS) that many MBE systems were designed and built specifically for metallic oxide deposition. More recently, some of these machines have also been employed to synthesize other interesting oxides, for example, ferroelectrics and ferromagnets. In all these studies, RHEED has been the principal diagnostic tool and source of information about the growing film surface.
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Lenz, Oliver, Andrea Gleiche, Angelika Strack y Bärbel Friedrich. "Requirements for Heterologous Production of a Complex Metalloenzyme: the Membrane-Bound [NiFe] Hydrogenase". Journal of Bacteriology 187, n.º 18 (15 de septiembre de 2005): 6590–95. http://dx.doi.org/10.1128/jb.187.18.6590-6595.2005.
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ABSTRACT By taking advantage of the tightly clustered genes for the membrane-bound [NiFe] hydrogenase of Ralstonia eutropha H16, broad-host-range recombinant plasmids were constructed carrying the entire membrane-bound hydrogenase (MBH) operon encompassing 21 genes. We demonstrate that the complex MBH biosynthetic apparatus is actively produced in hydrogenase-free hosts yielding fully assembled and functional MBH protein.
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Rosbjerg, Anne, Mikkel-Ole Skjoedt y Peter Garred. "MBL/ficolin associated protein-1 inhibits the complex formation between MASPs and MBL". Immunobiology 217, n.º 11 (noviembre de 2012): 1186. http://dx.doi.org/10.1016/j.imbio.2012.08.165.
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