Academic literature on the topic 'CIN-TCP proteins'

TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR 1 and 2 (TCP) family proteins are the plant-specific transcription factors extensively participating in diverse developmental processes by integrating external cues with internal signals. The roles of CINCINNATA (CIN)-like TCPs are conserved in control of the morphology and size of leaves, petal development, trichome formation and plant flowering. The tight regulation of CIN-like TCP activity at transcriptional and post-transcriptional levels are central for plant developmental plasticity in response to the ever-changing environmental conditions. In this review, we summarize recent progresses with regard to the function and regulation of CIN-like TCPs. CIN-like TCPs are regulated by abiotic and biotic cues including light, temperature and pathogens. They are also finely controlled by microRNA319 (miRNA319), chromatin remodeling complexes and auxin homeostasis. The protein degradation plays critical roles in tightly controlling the activity of CIN-like TCPs as well.

The plant-specific Teosinte-branched 1/Cycloidea/Proliferating (TCP) transcription factor genes are involved in plants’ development, hormonal pathways, and stress response but their evolutionary history is uncertain. The genome-wide analysis performed here for 47 plant species revealed 535 TCP candidates in terrestrial plants and none in aquatic plants, and that TCP family genes originated early in the history of land plants. Phylogenetic analysis divided the candidate genes into Classes I and II, and Class II was further divided into CYCLOIDEA (CYC) and CINCINNATA (CIN) clades; CYC is more recent and originated from CIN in angiosperms. Protein architecture, intron pattern, and sequence characteristics were conserved in each class or clade supporting this classification. The two classes significantly expanded through whole-genome duplication during evolution. Expression analysis revealed the conserved expression of TCP genes from lower to higher plants. The expression patterns of Class I and CIN genes in different stages of the same tissue revealed their function in plant development and their opposite effects in the same biological process. Interaction network analysis showed that TCP proteins tend to form protein complexes, and their interaction networks were conserved during evolution. These results contribute to further functional studies on TCP family genes.

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.

The plant-specific TCP family proteins play an important role in the processes of plant growth and development. Broussonetia papyrifera is a versatile perennial deciduous tree, and its genome data have been published. However, no comprehensive analysis of the TCP gene family in B. papyrifera has been undertaken. In this study, 20 BpTCP genes (BpTCPs) were identified in the B. papyrifera genome. Phylogenetic analysis divided BpTCPs into three subclades, the PCF subclade, the CIN subclade and the CYC/TB1 subclade. Gene structure analysis displayed that all BpTCPs except BpTCP19 contained one coding region. Conserved motif analysis showed that BpTCP proteins in the same subclade possessed similar motif structures. Segmental duplication was the primary driving force for the expansion of BpTCPs. Expression patterns showed that BpTCPs may play diverse biological functions in organ or tissue development. Transcriptional activation activity analysis of BpTCP8, BpTCP14 and BpTCP19 showed that they possessed transcriptional activation ability. The ectopic expression analysis in Arabidopsis wild-type and AtBRC1 ortholog mutant showed that BpTCP8, BpTCP14 and BpTCP19 could prevent rosette branch outgrowth. Collectively, our study not only established the first genome-wide analysis of the B. papyrifera TCP gene family, but also provided valuable information for understanding the function of BpTCPs in shoot branching.

The plant-specific TCP transcription factors are well-characterized in both monocots and dicots, which have been implicated in multiple aspects of plant biological processes such as leaf morphogenesis and senescence, lateral branching, flower development and hormone crosstalk. However, no systematic analysis of the petunia TCP gene family has been described. In this work, a total of 66 petunia TCP genes (32 PaTCP genes in P. axillaris and 34 PiTCP genes in P. inflata) were identified. Subsequently, a systematic analysis of 32 PaTCP genes was performed. The phylogenetic analysis combined with structural analysis clearly distinguished the 32 PaTCP proteins into two classes—class Ι and class Ⅱ. Class Ⅱ was further divided into two subclades, namely, the CIN-TCP subclade and the CYC/TB1 subclade. Plenty of cis-acting elements responsible for plant growth and development, phytohormone and/or stress responses were identified in the promoter of PaTCPs. Distinct spatial expression patterns were determined among PaTCP genes, suggesting that these genes may have diverse regulatory roles in plant growth development. Furthermore, differential temporal expression patterns were observed between the large- and small-flowered petunia lines for most PaTCP genes, suggesting that these genes are likely to be related to petal development and/or petal size in petunia. The spatiotemporal expression profiles and promoter analysis of PaTCPs indicated that these genes play important roles in petunia diverse developmental processes that may work via multiple hormone pathways. Moreover, three PaTCP-YFP fusion proteins were detected in nuclei through subcellular localization analysis. This is the first comprehensive analysis of the petunia TCP gene family on a genome-wide scale, which provides the basis for further functional characterization of this gene family in petunia.

As a magnoliid angiosperm, the Liriodendron chinense (Hamsl) Sarg in the Magnoliaceae family is susceptible to external environmental factors. The TEOSINTE BRANCHED 1/CYCLOIDEA/PROLIFERATING CELL FACTORS (TCP) proteins known for their growth and developmental biological roles have been identified in various plant species but not in the Liriodendron chinense. In this study, 15 TCP genes were identified in the L. chinense genome, and categorized into two classes, termed class I (PCF) and class II (CIN and CYC/TB1). A total of 14 TCP genes were located on the 10 chromosomes, and the remaining one, on a contig. Multispecies phylogenetic tree analysis supported the classification of identified LcTCP genes and exhibited that the expansion of the LcTCP gene family was before the angiosperm evolutionary divergence times. Additional gene duplication investigations revealed a purifying selection pressure during evolution history. Moreover, the LcTCP genes were also observed to have various cis-acting elements related to plant growth and development, phytohormone regulations, and abiotic stress responses. Gene expression pattern analysis also paraded that LcTCP genes play a crucial role in abiotic stress regulations. In particular, LcTCP1 in all stresses investigated. Overall, our findings suggest a pivotal role for the TCP gene family during external environmental stresses in L. chinense. This study will provide valuable information on the identification and function of the LcTCPs during abiotic stresses, paving the way for further research on the functional verification of L. chinense TCPs.

Plant-specific transcription factors such as the TCP family play crucial roles in light responses and lateral branching. The commercial development of S. muricatum has been influenced by the ease with which its lateral branches can be germinated, especially under greenhouse cultivation during the winter with supplemented LED light. The present study examined the TCP family genes in S. muricatum using bioinformatics analysis (whole-genome sequencing and RNA-seq) to explore the response of this family to different light treatments. Forty-one TCP genes were identified through a genome-wide search; phylogenetic analysis revealed that the CYC/TB1, CIN and Class I subclusters contained 16 SmTCP, 11 SmTCP and 14 SmTCP proteins, respectively. Structural and conserved sequence analysis of SmTCPs indicated that the motifs in the same subcluster were highly similar in structure and the gene structure of SmTCPs was simpler than that in Arabidopsis thaliana; 40 of the 41 SmTCPs were localized to 12 chromosomes. In S. muricatum, 17 tandem repeat sequences and 17 pairs of SmTCP genes were found. We identified eight TCPs that were significantly differentially expressed (DETCPs) under blue light (B) and red light (R), using RNA-seq. The regulatory network of eight DETCPs was preliminarily constructed. All three subclusters responded to red and blue light treatment. To explore the implications of regulatory TCPs in different light treatments for each species, the TCP regulatory gene networks and GO annotations for A. thaliana and S. muricatum were compared. The regulatory mechanisms suggest that the signaling pathways downstream of the TCPs may be partially conserved between the two species. In addition to the response to light, functional regulation was mostly enriched with auxin response, hypocotyl elongation, and lateral branch genesis. In summary, our findings provide a basis for further analysis of the TCP gene family in other crops and broaden the functional insights into TCP genes regarding light responses.

Abstract Background TCP-domain proteins, plant specific transcription factors, play important roles in various developmental processes. CIN-TCPs control leaf curvature in simple leaf species while regulate leaf complexity in compound leaf species. However, the knowledge was largely based on findings in few model species. To extend our knowledge on this group of proteins in Solanaceae species, we identified a CIN-TCP gene from petunia, and studied its functions using virus-induced gene silencing (VIGS). Results Consistently, silencing of CIN-TCPs increases complexity of tomato leaves, and enhances leaf curvature in Nicotiana benthamiana. However, in petunia (Petunia hybrida), silencing of petunia LA, a CIN-TCP, through VIGS did not obviously affect leaf shape. The silencing, however, enhanced petal curvature. The event was associated with petal expansion at the distal portion where epidermal cell size along the midribs was also increased. The enlarged epidermal cells became flattened. Although shapes of PhLA-silenced flowers largely resemble phmyb1 mutant phenotype, PhMYB1 expression was not affected when PhLA was specifically silenced. Therefore, both PhLA and PhMYB1 are required to regulate flower morphology. In corolla, PhLA and miR319 deferentially express in different regions with strong expressions in limb and tube region respectively. Conclusions In conclusion, unlike LA-like genes in tomato and N. benthamiana, PhLA plays a more defined role in flower morphogenesis, including petal curvature and epidermal cell differentiation.

The TCP gene family encodes non-canonical bHLH transcription factors that act as key regulatory molecules in diverse developmental processes in plants including organ morphogenesis, plant architecture, leaf maturation, and flowering transition. In this study, we assign a number of new functions to the CINCINNATA-like TCP (CIN-TCP) proteins throughout the life of Arabidopsis thaliana starting from light-mediated seedling morphogenesis, regulation of simple leaf architecture, and hormone homeostasis during leaf senescence. PART-I: Role of TCP transcription factors in light-mediated Arabidopsis seedling development Plant growth and morphogenesis rely heavily on the coordination between external and internal cues to cope with the ever-changing surroundings. In Arabidopsis seedlings grown under low light intensity, the embryonic stem (hypocotyl) elongates more in an attempt to reach the light source, a process called skotomorphogenesis. By contrast, seedlings grown under sufficient light grow shorter (photomorphogenesis). We had earlier shown that the CIN-TCPs promote cell elongation during photomorphogenesis. Here we show that this effect of CIN-TCPs is abolished in darkness, suggesting that CIN-TCP-mediated cell elongation is dependent on the light-signaling pathway. By analyzing hypocotyl elongation under various light qualities, we show that TCP4-mediated hypocotyl cell elongation is dependent on phytochrome B (PhyB) photoreceptor under diverse light conditions. Using various biochemical and genetic assays, we demonstrate that TCP4 activation leads to the stabilization of several phytochrome-interacting factor (PIF) proteins through protein-protein interaction. Enhanced PIF level leads to the destabilization of PhyB and indirectly represses the HFR1 protein to promote hypocotyl elongation. Thus, CIN-TCP functions as a major negative regulator of photomorphogenic seedling growth together with PIF. PART-II: CIN-TCPs actively suppress leaflet emergence to promote simple leaf form Though all angiosperm leaves are initiated as simple rod-like primordia at the flank of the shoot apical meristem (SAM), they show extensive shape diversity at maturity, based on which they are broadly divided into two forms; simple leaves with intact lamina and compound leaves with lamina dissected into leaflets. Although genetic intervention has converted compound leaves into simpler or more complex variants, it is not clear whether, or to what extent, simple leaves can initiate leaflets and form compound architecture upon endogenous gene manipulation. Here, we show that simultaneous down-regulation of CIN-TCP and class II KNOTTED1-LIKE (KNOX-II) proteins converts simple Arabidopsis lamina to super-compound form with reiterative and indeterminate leaflet emergence, accompanied with sustained reactivation of the meristem-specific genes including KNOX-I and CUPSHAPED COTYLEDON (CUC). CIN-TCPs activate KNOX-II and a dominant CIN-TCP member restores simple leaf form. These results offer a framework of simple leaf development wherein CIN-TCP-KNOX-II forms a strong differentiation module that suppresses the KNOX-I-CUC network and leaflet initiation in the primordia. PART-III: CIN-TCPs maintain jasmonic acid homeostasis during leaf senescence through an incoherent feed forward loop (IFFL) The class I and class II TCP transcription factors, divided based on their sequence diversity, display functional antagonism in regulating multiple cellular and physiological processes including jasmonic acid (JA) biosynthesis during leaf senescence, the final stage of leaf development. Five members of miR319-regulated class II TCPs (TCP2, 3, 4, 10 & 24), also called CIN-TCPs, redundantly promote the JA-biosynthetic enzyme-encoding gene LIPOXYGENASE2 (LOX2). For example, TCP4 binds to the LOX2 promoter and directly activates its transcription that induces leaf senescence. By contrast, the class I TCP members TCP9 and TCP20, together with TCP8 and TCP22, are recruited on the LOX2 promoter to repress its transcription. However, a molecular link between these two TCP groups in regulating LOX2 transcription has not been demonstrated. We here demonstrate a novel type I incoherent feed forward loop (IFFL) formed by the direct transcriptional link between class I (TCP9) and class II TCP proteins (TCP4/ TCP10) to balance the LOX2 expression dynamics. By combined mathematical modelling and genetic manipulation, we show that this IFFL filters out the stochastic noise in TCP and maintains a robust level of LOX2. Thus, the TCP4/TCP10-TCP9-LOX2 module regulates JA homeostasis and leaf senescence in Arabidopsis. In conclusion, we show that the CIN-TCP proteins, along with their class II members, regulate important developmental processes throughout the life of Arabidopsis starting from the seedling establishment, simple leaf shape, and hormone homeostasis. Studies on the role of CIN-TCP homologs in other species would test whether these functions are conserved in evolution.