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Journal articles on the topic 'SF2 helicase'

Author: Grafiati

Published: 14 March 2023

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1

Gilman, Benjamin, Pilar Tijerina, and Rick Russell. "Distinct RNA-unwinding mechanisms of DEAD-box and DEAH-box RNA helicase proteins in remodeling structured RNAs and RNPs." Biochemical Society Transactions 45, no. 6 (November 17, 2017): 1313–21. http://dx.doi.org/10.1042/bst20170095.

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Structured RNAs and RNA–protein complexes (RNPs) fold through complex pathways that are replete with misfolded traps, and many RNAs and RNPs undergo extensive conformational changes during their functional cycles. These folding steps and conformational transitions are frequently promoted by RNA chaperone proteins, notably by superfamily 2 (SF2) RNA helicase proteins. The two largest families of SF2 helicases, DEAD-box and DEAH-box proteins, share evolutionarily conserved helicase cores, but unwind RNA helices through distinct mechanisms. Recent studies have advanced our understanding of how their distinct mechanisms enable DEAD-box proteins to disrupt RNA base pairs on the surfaces of structured RNAs and RNPs, while some DEAH-box proteins are adept at disrupting base pairs in the interior of RNPs. Proteins from these families use these mechanisms to chaperone folding and promote rearrangements of structured RNAs and RNPs, including the spliceosome, and may use related mechanisms to maintain cellular messenger RNAs in unfolded or partially unfolded conformations.

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2

Seybert, Anja, Leonie C. van Dinten, Eric J. Snijder, and John Ziebuhr. "Biochemical Characterization of the Equine Arteritis Virus Helicase Suggests a Close Functional Relationship between Arterivirus and Coronavirus Helicases." Journal of Virology 74, no. 20 (October 15, 2000): 9586–93. http://dx.doi.org/10.1128/jvi.74.20.9586-9593.2000.

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ABSTRACT The arterivirus equine arteritis virus nonstructural protein 10 (nsp10) has previously been predicted to contain a Zn finger structure linked to a superfamily 1 (SF1) helicase domain. A recombinant form of nsp10, MBP-nsp10, was produced in Escherichia coli as a fusion protein with the maltose-binding protein. The protein was partially purified by affinity chromatography and shown to have ATPase activity that was strongly stimulated by poly(dT), poly(U), and poly(dA) but not by poly(G). The protein also had both RNA and DNA duplex-unwinding activities that required the presence of 5′ single-stranded regions on the partial-duplex substrates, indicating a 5′-to-3′ polarity in the unwinding reaction. Results of this study suggest a close functional relationship between the arterivirus nsp10 and the coronavirus helicase, for which NTPase and duplex-unwinding activities were recently demonstrated. In a number of biochemical properties, both arterivirus and coronavirus SF1 helicases differ significantly from the previously characterized RNA virus SF1 and SF2 enzymes. Thus, the combined data strongly support the idea that nidovirus helicases may represent a separate group of RNA virus-encoded helicases with distinct properties.

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3

Fan, Li, and Kevin T. DuPrez. "XPB: An unconventional SF2 DNA helicase." Progress in Biophysics and Molecular Biology 117, no. 2-3 (March 2015): 174–81. http://dx.doi.org/10.1016/j.pbiomolbio.2014.12.005.

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4

Woodman, Isabel L., and Edward L. Bolt. "Molecular biology of Hel308 helicase in archaea." Biochemical Society Transactions 37, no. 1 (January 20, 2009): 74–78. http://dx.doi.org/10.1042/bst0370074.

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Hel308 is an SF2 (superfamily 2) helicase with clear homologues in metazoans and archaea, but not in fungi or bacteria. Evidence from biochemistry and genetics implicates Hel308 in remodelling compromised replication forks. In the last 4 years, significant advances have been made in understanding the biochemistry of archaeal Hel308, most recently through atomic structures from cren- and eury-archaea. These are good templates for SF2 helicase function more generally, highlighting co-ordinated actions of accessory domains around RecA folds. We review the emerging molecular biology of Hel308, drawing together ideas of how it may contribute to genome stability through the control of recombination, with reference to paradigms developed in bacteria.

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5

Du Pont, Kelly E., Russell B. Davidson, Martin McCullagh, and Brian J. Geiss. "Motif V regulates energy transduction between the flavivirus NS3 ATPase and RNA-binding cleft." Journal of Biological Chemistry 295, no. 6 (December 30, 2019): 1551–64. http://dx.doi.org/10.1074/jbc.ra119.011922.

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The unwinding of dsRNA intermediates is critical for the replication of flavivirus RNA genomes. This activity is provided by the C-terminal helicase domain of viral nonstructural protein 3 (NS3). As a member of the superfamily 2 (SF2) helicases, NS3 requires the binding and hydrolysis of ATP/NTP to translocate along and unwind double-stranded nucleic acids. However, the mechanism of energy transduction between the ATP- and RNA-binding pockets is not well-understood. Previous molecular dynamics simulations conducted by our group have identified Motif V as a potential “communication hub” for this energy transduction pathway. To investigate the role of Motif V in this process, here we combined molecular dynamics, biochemistry, and virology approaches. We tested Motif V mutations in both the replicon and recombinant protein systems to investigate viral genome replication, RNA-binding affinity, ATP hydrolysis activity, and helicase-mediated unwinding activity. We found that the T407A and S411A substitutions in NS3 reduce viral replication and increase the helicase-unwinding turnover rates by 1.7- and 3.5-fold, respectively, suggesting that flaviviruses may use suboptimal NS3 helicase activity for optimal genome replication. Additionally, we used simulations of each mutant to probe structural changes within NS3 caused by each mutation. These simulations indicate that Motif V controls communication between the ATP-binding pocket and the helical gate. These results help define the linkage between ATP hydrolysis and helicase activities within NS3 and provide insight into the biophysical mechanisms for ATPase-driven NS3 helicase function.

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6

Moukhtar, Mirna, Wafi Chaar, Ziad Abdel-Razzak, Mohamad Khalil, Samir Taha, and Hala Chamieh. "ARCPHdb: A comprehensive protein database for SF1 and SF2 helicase from archaea." Computers in Biology and Medicine 80 (January 2017): 185–89. http://dx.doi.org/10.1016/j.compbiomed.2016.12.004.

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7

Kawaoka, Jane, Eckhard Jankowsky, and Anna Marie Pyle. "Backbone tracking by the SF2 helicase NPH-II." Nature Structural & Molecular Biology 11, no. 6 (May 16, 2004): 526–30. http://dx.doi.org/10.1038/nsmb771.

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8

Halgasova, Nora, Radka Matuskova, Daniel Kraus, Adela Tkacova, Lenka Balusikova, and Gabriela Bukovska. "Gp41, a superfamily SF2 helicase from bacteriophage BFK20." Virus Research 245 (February 2018): 7–16. http://dx.doi.org/10.1016/j.virusres.2017.12.005.

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9

Romero, Zachary J., Stefanie H. Chen, Thomas Armstrong, Elizabeth A. Wood, Antoine van Oijen, Andrew Robinson, and Michael M. Cox. "Resolving Toxic DNA repair intermediates in every E. coli replication cycle: critical roles for RecG, Uup and RadD." Nucleic Acids Research 48, no. 15 (July 9, 2020): 8445–60. http://dx.doi.org/10.1093/nar/gkaa579.

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Abstract DNA lesions or other barriers frequently compromise replisome progress. The SF2 helicase RecG is a key enzyme in the processing of postreplication gaps or regressed forks in Escherichia coli. A deletion of the recG gene renders cells highly sensitive to a range of DNA damaging agents. Here, we demonstrate that RecG function is at least partially complemented by another SF2 helicase, RadD. A ΔrecGΔradD double mutant exhibits an almost complete growth defect, even in the absence of stress. Suppressors appear quickly, primarily mutations that compromise priA helicase function or recA promoter mutations that reduce recA expression. Deletions of uup (encoding the UvrA-like ABC system Uup), recO, or recF also suppress the ΔrecGΔradD growth phenotype. RadD and RecG appear to avoid toxic situations in DNA metabolism, either resolving or preventing the appearance of DNA repair intermediates produced by RecA or RecA-independent template switching at stalled forks or postreplication gaps. Barriers to replisome progress that require intervention by RadD or RecG occur in virtually every replication cycle. The results highlight the importance of the RadD protein for general chromosome maintenance and repair. They also implicate Uup as a new modulator of RecG function.

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10

Hajj, Mirna, Petra Langendijk-Genevaux, Manon Batista, Yves Quentin, Sébastien Laurent, Régine Capeyrou, Ziad Abdel-Razzak, et al. "Phylogenetic Diversity of Lhr Proteins and Biochemical Activities of the Thermococcales aLhr2 DNA/RNA Helicase." Biomolecules 11, no. 7 (June 26, 2021): 950. http://dx.doi.org/10.3390/biom11070950.

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Helicase proteins are known to use the energy of ATP to unwind nucleic acids and to remodel protein-nucleic acid complexes. They are involved in almost every aspect of DNA and RNA metabolisms and participate in numerous repair mechanisms that maintain cellular integrity. The archaeal Lhr-type proteins are SF2 helicases that are mostly uncharacterized. They have been proposed to be DNA helicases that act in DNA recombination and repair processes in Sulfolobales and Methanothermobacter. In Thermococcales, a protein annotated as an Lhr2 protein was found in the network of proteins involved in RNA metabolism. To investigate this, we performed in-depth phylogenomic analyses to report the classification and taxonomic distribution of Lhr-type proteins in Archaea, and to better understand their relationship with bacterial Lhr. Furthermore, with the goal of envisioning the role(s) of aLhr2 in Thermococcales cells, we deciphered the enzymatic activities of aLhr2 from Thermococcus barophilus (Tbar). We showed that Tbar-aLhr2 is a DNA/RNA helicase with a significant annealing activity that is involved in processes dependent on DNA and RNA transactions.

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11

Pugh, Robert A., Masayoshi Honda, Haley Leesley, Alvin Thomas, Yuyen Lin, Mark J. Nilges, Isaac K. O. Cann, and Maria Spies. "The Iron-containing Domain Is Essential in Rad3 Helicases for Coupling of ATP Hydrolysis to DNA Translocation and for Targeting the Helicase to the Single-stranded DNA-Double-stranded DNA Junction." Journal of Biological Chemistry 283, no. 3 (November 20, 2007): 1732–43. http://dx.doi.org/10.1074/jbc.m707064200.

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Helicases often achieve functional specificity through utilization of unique structural features incorporated into an otherwise conserved core. The archaeal Rad3 (xeroderma pigmentosum group D protein (XPD)) helicase is a prototypical member of the Rad3 family, distinct from other related (superfamily II) SF2 enzymes because of a unique insertion containing an iron-sulfur (FeS) cluster. This insertion may represent an auxiliary domain responsible for modifying helicase activity or for conferring specificity for selected DNA repair intermediates. The importance of the FeS cluster for the fine-tuning of Rad3-DNA interactions is illustrated by several clinically relevant point mutations in the FeS domain of human Bach1 (FancJ) and XPD helicases that result in distinct disease phenotypes. Here we analyzed the substrate specificity of the Rad3 (XPD) helicase from Ferroplasma acidarmanus (FacRad3) and probed the importance of the FeS cluster for Rad3-DNA interactions. We found that the FeS cluster stabilizes secondary structure of the auxiliary domain important for coupling of single-stranded (ss) DNA-dependent ATP hydrolysis to ssDNA translocation. Additionally, we observed specific quenching of the Cy5 fluorescent dye when the FeS cluster of a bound helicase is positioned in close proximity to a Cy5 fluorophore incorporated into the DNA molecule. Taking advantage of this Cy5 quenching, we developed an equilibrium assay for analysis of the Rad3 interactions with various DNA substrates. We determined that the FeS cluster-containing domain recognizes the ssDNA-double-stranded DNA junction and positions the helicase in an orientation consistent with duplex unwinding. Although it interacts specifically with the junction, the enzyme binds tightly to ssDNA, and the single-stranded regions of the substrate are the major contributors to the energetics of FacRad3-substrate interactions.

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12

Bonde, Nina J., Zachary J. Romero, Sindhu Chitteni-Pattu, and Michael M. Cox. "RadD is a RecA-dependent accessory protein that accelerates DNA strand exchange." Nucleic Acids Research 50, no. 4 (February 12, 2022): 2201–10. http://dx.doi.org/10.1093/nar/gkac041.

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Abstract In rapidly growing cells, with recombinational DNA repair required often and a new replication fork passing every 20 min, the pace of RecA-mediated DNA strand exchange is potentially much too slow for bacterial DNA metabolism. The enigmatic RadD protein, a putative SF2 family helicase, exhibits no independent helicase activity on branched DNAs. Instead, RadD greatly accelerates RecA-mediated DNA strand exchange, functioning only when RecA protein is present. The RadD reaction requires the RadD ATPase activity, does not require an interaction with SSB, and may disassemble RecA filaments as it functions. We present RadD as a new class of enzyme, an accessory protein that accelerates DNA strand exchange, possibly with a helicase-like action, in a reaction that is entirely RecA-dependent. RadD is thus a DNA strand exchange (recombination) synergist whose primary function is to coordinate closely with and accelerate the DNA strand exchange reactions promoted by the RecA recombinase. Multiple observations indicate a uniquely close coordination of RadD with RecA function.

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13

Smith, Corey L., and Craig L. Peterson. "A Conserved Swi2/Snf2 ATPase Motif Couples ATP Hydrolysis to Chromatin Remodeling." Molecular and Cellular Biology 25, no. 14 (July 2005): 5880–92. http://dx.doi.org/10.1128/mcb.25.14.5880-5892.2005.

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ABSTRACT Yeast (Saccharomyces cerevisiae) SWI/SNF is a prototype for a large family of ATP-dependent chromatin-remodeling enzymes that facilitate numerous DNA-mediated processes. Swi2/Snf2 is the catalytic subunit of SWI/SNF, and it is the founding member of a novel subfamily of the SF2 superfamily of DNA helicase/ATPases. Here we present a functional analysis of the diagnostic set of helicase/ATPase sequence motifs found within all Swi2p/Snf2p family members. Whereas many of these motifs play key roles in ATP binding and/or hydrolysis, we identify residues within conserved motif V that are specifically required to couple ATP hydrolysis to chromatin-remodeling activity. Interestingly, motif V of the human Swi2p/Snf2p homolog, Brg1p, has been shown to be a possible hot spot for mutational alterations associated with cancers.

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14

Masterson, Philip J., Margaret A. Stanley, Alan P. Lewis, and Michael A. Romanos. "A C-Terminal Helicase Domain of the Human Papillomavirus E1 Protein Binds E2 and the DNA Polymerase α-Primase p68 Subunit." Journal of Virology 72, no. 9 (September 1, 1998): 7407–19. http://dx.doi.org/10.1128/jvi.72.9.7407-7419.1998.

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ABSTRACT The human papillomavirus (HPV) E1 and E2 proteins bind cooperatively to the viral origin of replication (ori), forming an E1-E2-ori complex that is essential for initiation of DNA replication. All other replication proteins, including DNA polymerase α-primase (polα-primase), are derived from the host cell. We have carried out a detailed analysis of the interactions of HPV type 16 (HPV-16) E1 with E2, ori, and the four polα-primase subunits. Deletion analysis showed that a C-terminal region of E1 (amino acids [aa] 432 to 583 or 617) is required for E2 binding. HPV-16 E1 was unable to bind theori in the absence of E2, but the same C-terminal domain of E1 was sufficient to tether E1 to the ori via E2. Of the polα-primase subunits, only p68 bound E1, and binding was competitive with E2. The E1 region required (aa 397 to 583) was the same as that required for E2 binding but additionally contained 34 N-terminal residues. In confirmation of these differences, we found that a monoclonal antibody, mapping adjacent to the N-terminal junction of the p68-binding region, blocked E1-p68 but not E1-E2 binding. Sequence alignments and secondary-structure prediction for HPV-16 E1 and other superfamily 3 (SF3) viral helicases closely parallel the mapping data in suggesting that aa 439 to 623 constitute a discrete helicase domain. Assuming a common nucleoside triphosphate-binding fold, we have generated a structural model of this domain based on the X-ray structures of the hepatitis C virus and Bacillus stearothermophilus (SF2) helicases. The modelling closely matches the deletion analysis in suggesting that this region of E1 is indeed a structural domain, and our results suggest that it is multifunctional and critical to several stages of HPV DNA replication.

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15

Jangra, Rohit K., MinKyung Yi, and Stanley M. Lemon. "DDX6 (Rck/p54) Is Required for Efficient Hepatitis C Virus Replication but Not for Internal Ribosome Entry Site-Directed Translation." Journal of Virology 84, no. 13 (April 14, 2010): 6810–24. http://dx.doi.org/10.1128/jvi.00397-10.

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ABSTRACT DDX6 (Rck/p54) is an evolutionarily conserved member of the SF2 DEAD-box RNA helicase family that contributes to the regulation of translation and storage and the degradation of cellular mRNAs. It interacts with multiple proteins and is a component of the micro-RNA (miRNA)-induced silencing complex (miRISC). Since miRNA-122 (miR-122) is essential for efficient hepatitis C virus (HCV) replication, we investigated the requirement for DDX6 in HCV replication in cultured hepatoma cells. Small interfering RNA (siRNA)-mediated knockdown of DDX6 and rescue with an siRNA-resistant mutant demonstrated that DDX6 expression is indeed required for optimal HCV replication. However, DDX6 knockdown did not impair miR-122 biogenesis or alter HCV responsiveness to miR-122 supplementation. Overexpression of DDX6 fused to EYFP (EYFP-DDX6) enhanced replication, whereas a helicase-deficient mutant with a substitution in the conserved DEAD-box motif II (DQAD) had a dominant-negative effect, reducing HCV yields. Coimmunoprecipitation experiments revealed an intracellular complex containing DDX6, HCV core protein, and both viral and cellular RNAs, the formation of which was dependent upon the C-terminal domain of DDX6 but not DDX6 helicase activity. However, since DDX6 abundance influenced the replication of subgenomic HCV RNAs lacking core sequence, the relevance of this complex is uncertain. Importantly, DDX6 knockdown caused minimal reductions in cellular proliferation, generally stimulated cellular translation ([35S]Met incorporation), and did not impair translation directed by the HCV internal ribosome entry site. Thus, DDX6 helicase activity is essential for efficient HCV replication, reflecting essential roles for DDX6 in HCV genome amplification and/or maintenance of cellular homeostasis.

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16

CHINO, MAKOTO, KIYOHIRO NISHIKAWA, RYUICHI SAWA, MASA HAMADA, HIROSHI NAGANAWA, TSUTOMU SAWA, and TOMIO TAKEUCHI. "Heliquinomycin, a New Inhibitor of DNA Helicase, Produced by Streptomyces sp. MJ929-SF2. III. Biosynthesis." Journal of Antibiotics 50, no. 9 (1997): 781–84. http://dx.doi.org/10.7164/antibiotics.50.781.

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17

Mackeldanz, Petra, Jürgen Alves, Elisabeth Möncke-Buchner, Karol H. Wyszomirski, Detlev H. Krüger, and Monika Reuter. "Functional consequences of mutating conserved SF2 helicase motifs in the Type III restriction endonuclease EcoP15I translocase domain." Biochimie 95, no. 4 (April 2013): 817–23. http://dx.doi.org/10.1016/j.biochi.2012.11.014.

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18

CHINO, MAKOTO, KIYOHIRO NISHIKAWA, TOSHIO TSUCHIDA, RYUICHI SAWA, HIKARU NAKAMURA, KAZUO T. NAKAMURA, YASUHIKO MURAOKA, et al. "Heliquinomycin, a New Inhibitor of DNA Helicase, Produced by Streptomyces sp. MJ929-SF2.II. Structure Determination of Heliquinomycin." Journal of Antibiotics 50, no. 2 (1997): 143–46. http://dx.doi.org/10.7164/antibiotics.50.143.

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19

Gajewski, Stefan, Michael R. Webb, Vitold Galkin, Edward H. Egelman, Kenneth N. Kreuzer, and Stephen W. White. "Crystal Structure of the Phage T4 Recombinase UvsX and Its Functional Interaction with the T4 SF2 Helicase UvsW." Journal of Molecular Biology 405, no. 1 (January 2011): 65–76. http://dx.doi.org/10.1016/j.jmb.2010.10.004.

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20

CHINO, M., K. NISHIKAWA, R. SAWA, M. HAMADA, H. NAGANAWA, T. SAWA, and T. TAKEUCHI. "ChemInform Abstract: Heliquinomycin, a New Inhibitor of DNA Helicase, Produced by Streptomyces sp. MJ929-SF2. Part 3. Biosynthesis." ChemInform 29, no. 9 (June 23, 2010): no. http://dx.doi.org/10.1002/chin.199809242.

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21

CHINO, M., K. NISHIKAWA, T. TSUCHIDA, R. SAWA, H. NAKAMURA, K. T. NAKAMURA, Y. MURAOKA, et al. "ChemInform Abstract: Heliquinomycin, a New Inhibitor of DNA Helicase, Produced by Streptomyces Sp. MJ929-SF2. Part 2. Structure Determination of Heliquinomycin." ChemInform 28, no. 30 (August 3, 2010): no. http://dx.doi.org/10.1002/chin.199730221.

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22

Zhang, Xianduo, Jianbo Song, Liping Wang, Zhi Min Yang, and Di Sun. "Identification of a DEAD-Box RNA Helicase BnRH6 Reveals Its Involvement in Salt Stress Response in Rapeseed (Brassica napus)." International Journal of Molecular Sciences 24, no. 1 (December 20, 2022): 2. http://dx.doi.org/10.3390/ijms24010002.

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Rapeseed (Brassica napus) is one of the most important vegetable oil crops worldwide. Abiotic stresses such as salinity are great challenges for its growth and productivity. DEAD-box RNA helicase 6 (RH6) is a subfamily member of superfamily 2 (SF2), which plays crucial roles in plant growth and development. However, no report is available on RH6 in regulating plant abiotic stress response. This study investigated the function and regulatory mechanism for BnRH6. BnRH6 was targeted to the nucleus and cytoplasmic processing body (P-body), constitutively expressed throughout the lifespan, and induced by salt stress. Transgenic overexpressing BnRH6 in Brassica and Arabidopsis displayed salt hypersensitivity, manifested by lagging seed germination (decreased to 55%–85% of wild-type), growth stunt, leaf chlorosis, oxidative stress, and over-accumulation of Na ions with the K+/Na+ ratio being decreased by 18.3%–28.6%. Given the undesirable quality of knockout Brassica plants, we utilized an Arabidopsis T-DNA insertion mutant rh6-1 to investigate downstream genes by transcriptomics. We constructed four libraries with three biological replicates to investigate global downstream genes by RNA sequencing. Genome-wide analysis of differentially expressed genes (DEGs) (2-fold, p < 0.05) showed that 41 genes were upregulated and 66 genes were downregulated in rh6-1 relative to wild-type under salt stress. Most of them are well-identified and involved in transcription factors, ABA-responsive genes, and detoxified components or antioxidants. Our research suggests that BnRH6 can regulate a group of salt-tolerance genes to negatively promote Brassica adaptation to salt stress.

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23

Fairman-Williams, Margaret E., Ulf-Peter Guenther, and Eckhard Jankowsky. "SF1 and SF2 helicases: family matters." Current Opinion in Structural Biology 20, no. 3 (June 2010): 313–24. http://dx.doi.org/10.1016/j.sbi.2010.03.011.

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24

Thomas, Christopher A., Jonathan M. Craig, Shuichi Hoshika, Andrew H. Laszlo, Jesse R. Huang, Sarah J. Abell, Hwanhee C. Kim, et al. "C-Glycoside DNA bases from an artificially expanded genetic information system reduce processivity in a SF2 helicase as revealed by nanopore tweezers." Biophysical Journal 121, no. 3 (February 2022): 209a—210a. http://dx.doi.org/10.1016/j.bpj.2021.11.1671.

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25

CHINO, MAKOTO, KIYOHIRO NISHIKAWA, MAYA UMEKITA, CHIGUSA HAYASHI, TAKAKO YAMAZAKI, TOSHIO TSUCHIDA, TSUTOMU SAWA, MASA HAMADA, and TOMIO TAKEUCHI. "Heliquinomycin, a New Inhibitor of DNA Helicase, Produced by Streptomyces sp. MJ929-SF2. I. Taxonomy, Production, Isolation, Physico-chemical Properties and Biological Activities." Journal of Antibiotics 49, no. 8 (1996): 752–57. http://dx.doi.org/10.7164/antibiotics.49.752.

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26

CHINO, M., K. NISHIKAWA, M. UMEKITA, C. HAYASHI, T. YAMAZAKI, T. TSUCHIDA, T. SAWA, M. HAMADA, and T. TAKEUCHI. "ChemInform Abstract: Heliquinomycin, a New Inhibitor of DNA Helicase, Produced by Streptomyces sp. MJ929-SF2. Part 1. Taxonomy, Production, Isolation, Physico-Chemical Properties and Biological Activities." ChemInform 28, no. 6 (August 4, 2010): no. http://dx.doi.org/10.1002/chin.199706230.

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27

Chamieh, Hala, Hiba Ibrahim, and Juliana Kozah. "Genome-wide identification of SF1 and SF2 helicases from archaea." Gene 576, no. 1 (January 2016): 214–28. http://dx.doi.org/10.1016/j.gene.2015.10.007.

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28

Hanet, Aoife, Felix Räsch, Ramona Weber, Vincenzo Ruscica, Maria Fauser, Tobias Raisch, Duygu Kuzuoğlu-Öztürk, et al. "HELZ directly interacts with CCR4–NOT and causes decay of bound mRNAs." Life Science Alliance 2, no. 5 (September 30, 2019): e201900405. http://dx.doi.org/10.26508/lsa.201900405.

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Eukaryotic superfamily (SF) 1 helicases have been implicated in various aspects of RNA metabolism, including transcription, processing, translation, and degradation. Nevertheless, until now, most human SF1 helicases remain poorly understood. Here, we have functionally and biochemically characterized the role of a putative SF1 helicase termed “helicase with zinc-finger,” or HELZ. We discovered that HELZ associates with various mRNA decay factors, including components of the carbon catabolite repressor 4-negative on TATA box (CCR4–NOT) deadenylase complex in human and Drosophila melanogaster cells. The interaction between HELZ and the CCR4–NOT complex is direct and mediated by extended low-complexity regions in the C-terminal part of the protein. We further reveal that HELZ requires the deadenylase complex to mediate translational repression and decapping-dependent mRNA decay. Finally, transcriptome-wide analysis of Helz-null cells suggests that HELZ has a role in the regulation of the expression of genes associated with the development of the nervous system.

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29

Chaar, Wafi, Hiba Ibrahim, Juliana Kozah, and Hala Chamieh. "Comparative analysis data of SF1 and SF2 helicases from three domains of life." Data in Brief 11 (April 2017): 510–16. http://dx.doi.org/10.1016/j.dib.2017.02.047.

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30

Pugh, Robert A., Colin G. Wu, and Maria Spies. "Regulation of translocation polarity by helicase domain 1 in SF2B helicases." EMBO Journal 31, no. 2 (November 11, 2011): 503–14. http://dx.doi.org/10.1038/emboj.2011.412.

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31

Korolev, Sergey, Timothy M. Lohman, Gabriel Waksman, Nanhua Yao, and Patricia C. Weber. "Comparisons between the structures of HCV and Rep helicases reveal structural similarities between SF1 and SF2 super-families of helicases." Protein Science 7, no. 3 (March 1998): 605–10. http://dx.doi.org/10.1002/pro.5560070309.

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32

Jedrzejczak, Robert, Jiawei Wang, Miroslawa Dauter, Roman J. Szczesny, Piotr P. Stepien, and Zbigniew Dauter. "Human Suv3 protein reveals unique features among SF2 helicases." Acta Crystallographica Section D Biological Crystallography 67, no. 11 (October 19, 2011): 988–96. http://dx.doi.org/10.1107/s0907444911040248.

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33

Sèle, Céleste, Frank Gabel, Irina Gutsche, Ivan Ivanov, Wim P. Burmeister, Frédéric Iseni, and Nicolas Tarbouriech. "Low-Resolution Structure of Vaccinia Virus DNA Replication Machinery." Journal of Virology 87, no. 3 (November 21, 2012): 1679–89. http://dx.doi.org/10.1128/jvi.01533-12.

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ABSTRACTSmallpox caused by the poxvirus variola virus is a highly lethal disease that marked human history and was eradicated in 1979 thanks to a worldwide mass vaccination campaign. This virus remains a significant threat for public health due to its potential use as a bioterrorism agent and requires further development of antiviral drugs. The viral genome replication machinery appears to be an ideal target, although very little is known about its structure. Vaccinia virus is the prototypic virus of theOrthopoxvirusgenus and shares more than 97% amino acid sequence identity with variola virus. Here we studied four essential viral proteins of the replication machinery: the DNA polymerase E9, the processivity factor A20, the uracil-DNA glycosylase D4, and the helicase-primase D5. We present the recombinant expression and biochemical and biophysical characterizations of these proteins and the complexes they form. We show that the A20D4 polymerase cofactor binds to E9 with high affinity, leading to the formation of the A20D4E9 holoenzyme. Small-angle X-ray scattering yielded envelopes for E9, A20D4, and A20D4E9. They showed the elongated shape of the A20D4 cofactor, leading to a 150-Å separation between the polymerase active site of E9 and the DNA-binding site of D4. Electron microscopy showed a 6-fold rotational symmetry of the helicase-primase D5, as observed for other SF3 helicases. These results favor a rolling-circle mechanism of vaccinia virus genome replication similar to the one suggested for tailed bacteriophages.

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Hickman, Alison Burgess, and Fred Dyda. "Binding and unwinding: SF3 viral helicases." Current Opinion in Structural Biology 15, no. 1 (February 2005): 77–85. http://dx.doi.org/10.1016/j.sbi.2004.12.001.

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Stopp, Marius, Philipp A. Steinmetz, and Gottfried Unden. "Properties of transmembrane helix TM1 of the DcuS sensor kinase of Escherichia coli, the stator for TM2 piston signaling." Biological Chemistry 402, no. 10 (August 6, 2021): 1239–46. http://dx.doi.org/10.1515/hsz-2021-0254.

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Abstract The sensor kinase DcuS of Escherichia coli perceives extracellular fumarate by a periplasmic PASP sensor domain. Transmembrane (TM) helix TM2, present as TM2-TM2′ homo-dimer, transmits fumarate activation in a piston-slide across the membrane. The second TM helix of DcuS, TM1, is known to lack piston movement. Structural and functional properties of TM1 were analyzed. Oxidative Cys-crosslinking (CL) revealed homo-dimerization of TM1 over the complete membrane, but only the central part showed α-helical +3/+4 spacing of the CL maxima. The GALLEX bacterial two-hybrid system indicates TM1/TM1′ interaction, and the presence of a TM1-TM1′ homo-dimer is suggested. The peripheral TM1 regions presented CL in a spacing atypical for α-helical arrangement. On the periplasmic side the deviation extended over 11 AA residues (V32-S42) between the α-helical part of TM1 and the onset of PASP. In the V32-S42 region, CL efficiency decreased in the presence of fumarate. Therefore, TM1 exists as a homo-dimer with α-helical arrangement in the central membrane region, and non-α-helical arrangement in the connector to PASP. The fumarate induced structural response in the V32-S42 region is suggested to represent a structural adaptation to the shift of TM2 in the TM1-TM1′/TM2-TM2′ four-helical bundle.

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Ruben, George C., and W. H. Stockmayer. "Evidence for helical structures in poly(l-olefin sulfones) by TEM." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 1 (August 1992): 276–77. http://dx.doi.org/10.1017/s0424820100121788.

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Advances in the techniques of TEM, including the preparation of ultrathin vertically shadowed platinum-carbon (Pt-C) replicas, have allowed the direct recognition of single-structural features, such as DNA , pectin helices or polysiloxane polymers. Here we report some observations on the chain conformations of serval poly (olefin sulfones). We find strong evidence for the presence of some helical conformations, which had been inferred for over a decade but could not so far be established by other methods.Unusual conformational behavior of poly(olefin sulfones) was indicated over twenty-five years ago. Dilute solutions of several poly (1-olefin sulfones), [-CH2-CHR-S02-]X, in non-polar solvents exhibited unexpectedly strong low-frequency dielectric dispersion, with relaxation times typical of rigid tumbling or of the terminal normal mode. In contrast, polysulfones made from olefins with internal double bonds show no low-frequency dielectric loss. To explain these facts, we refer to the crucial experiments of Fawcett and Fee (1982), who prepared terpolymers of 1-hexene,

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VAN DER KNAAP, Jan A., Vincent VAN DEN BOOM, Jeroen KUIPERS, Michiel J. T. VAN EIJK, Peter C. VAN DER VLIET, and H. Th Marc TIMMERS. "The gene for human TATA-binding-protein-associated factor (TAFII) 170: structure, promoter and chromosomal localization." Biochemical Journal 345, no. 3 (January 25, 2000): 521–27. http://dx.doi.org/10.1042/bj3450521.

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The TATA-binding protein (TBP) plays a central role in eukaryotic transcription and forms protein complexes with TBP-associated factors (TAFs). The genes encoding TAFII proteins frequently map to chromosomal regions altered in human neoplasias. TAFII170 of B-TFIID is a member of the SF2 superfamily of putative helicases. Members of this superfamily have also been implicated in several human genetic disorders. In this study we have isolated human genomic clones encoding TAFII170 and we show that the gene contains 37 introns. Ribonuclease-protection experiments revealed that TAFII170 has multiple transcription start sites, consistent with the observation that the promoter lacks a canonical TATA box and initiator element. Deletion analysis of the promoter region showed that a fragment of 264 bp is sufficient to direct transcription. In addition, we determined the chromosomal localization by two independent methods which mapped the gene to human chromosome 10q22-q23 between the markers D10S185 and WI-1183. The region surrounding these markers has been implicated in several human disorders.

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Böttcher, P., and H. Buchkremer-Hermanns. "Darstellung und Kristallstruktur des Bis(2-amino-1-ammonioethan)hexasulfids [H3N-(CH2)2-NH2]2S6 /Synthesis and Crystal Structure of Bis(2-amino-1-ammonioethan)hexasulfide, [H3N—(CH2)2-NH2]2S6." Zeitschrift für Naturforschung B 42, no. 3 (March 1, 1987): 267–71. http://dx.doi.org/10.1515/znb-1987-0303.

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Bis(2-amino-1-ammonioethan)hexasulfide has been synthesized from ethylendiamine, sulfur and hydrogensulfide in ethanolic solution. It consists of unbranched chains S62- (helical all-trans-conformation) and monoprotonated ethylenediamine cations; the latter show the uncommon synclinical conformation. A remarkable system of N - H···S-bridges links the S62-chains to form an infinite array. It crystallizes in the space group P1̄ with a = 9.203(4) Å, b = 9.921(4) Å, c = 15.583(5) Å, α = 93.03(3)°, β = 90.04(3)°, γ = 79.07(3)°

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PROUX-GILLARDEAUX, Véronique, Thierry GALLI, Isabelle CALLEBAUT, Anatoly MIKHAILIK, Georges CALOTHY, and Maria MARX. "D53 is a novel endosomal SNARE-binding protein that enhances interaction of syntaxin 1 with the synaptobrevin 2 complex in vitro." Biochemical Journal 370, no. 1 (February 15, 2003): 213–21. http://dx.doi.org/10.1042/bj20021309.

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Synaptobrevin 2 (Sb2), syntaxin1 (Stx1), and synaptosomal-associated protein of 25kDa (SNAP-25) are the main components of the soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) complex involved in fusion of synaptic vesicles with the presynaptic plasma membrane. We report the characterization of D53, a novel SNARE-binding protein preferentially expressed in neural and neuro-endocrine cells. Its two-dimensional organization, established by the hydrophobic cluster analysis, is reminiscent of SNARE proteins. D53 contains two putative helical regions, one of which includes a large coiled-coil domain involved in the interaction with Sb2 in vitro. Following subcellular fractionation, endogenous D53 was specifically detected in the membrane-containing fraction of PC12 cells, where it co-immunoprecipitated with Sb2. Analysis by confocal microscopy showed that, in these cells, endogenous D53 co-localized partially with the transferrin receptor in early endosomes. In vitro assays revealed that binding properties of D53 to Stx1 and Sb2 are comparable with those of SNAP-25. Furthermore, D53 forms Sb2/Stx1/D53 complexes in vitro in a manner similar to SNAP-25. We propose that D53 could be involved in the assembly or disassembly of endosomal SNARE complexes by regulating Sb2/Stx interaction.

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James, J. Anson, Carlos R. Escalante, Miran Yoon-Robarts, Thomas A. Edwards, R. Michael Linden, and Aneel K. Aggarwal. "Crystal Structure of the SF3 Helicase from Adeno-Associated Virus Type 2." Structure 11, no. 8 (August 2003): 1025–35. http://dx.doi.org/10.1016/s0969-2126(03)00152-7.

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Béguin, Pierre, Bruno Baron, Sukhvinder Gill, Nicole Charpin, and Patrick Forterre. "The SF1 helicase encoded by the archaeal plasmid pTN2 of Thermococcus nautili." Extremophiles 18, no. 4 (June 3, 2014): 779–87. http://dx.doi.org/10.1007/s00792-014-0658-5.

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Fradet-Turcotte, Amélie, Cary Moody, Laimonis A. Laimins, and Jacques Archambault. "Nuclear Export of Human Papillomavirus Type 31 E1 Is Regulated by Cdk2 Phosphorylation and Required for Viral Genome Maintenance." Journal of Virology 84, no. 22 (September 15, 2010): 11747–60. http://dx.doi.org/10.1128/jvi.01445-10.

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ABSTRACT The initiator protein E1 from human papillomavirus (HPV) is a helicase essential for replication of the viral genome. E1 contains three functional domains: a C-terminal enzymatic domain that has ATPase/helicase activity, a central DNA-binding domain that recognizes specific sequences in the origin of replication, and a N-terminal region necessary for viral DNA replication in vivo but dispensable in vitro. This N-terminal portion of E1 contains a conserved nuclear export signal (NES) whose function in the viral life cycle remains unclear. In this study, we provide evidence that nuclear export of HPV31 E1 is inhibited by cyclin E/A-Cdk2 phosphorylation of two serines residues, S92 and S106, located near and within the E1 NES, respectively. Using E1 mutant proteins that are confined to the nucleus, we determined that nuclear export of E1 is not essential for transient viral DNA replication but is important for the long-term maintenance of the HPV episome in undifferentiated keratinocytes. The findings that E1 nuclear export is not required for viral DNA replication but needed for genome maintenance over multiple cell divisions raised the possibility that continuous nuclear accumulation of E1 is detrimental to cellular growth. In support of this possibility, we observed that nuclear accumulation of E1 dramatically reduces cellular proliferation by delaying cell cycle progression in S phase. On the basis of these results, we propose that nuclear export of E1 is required, at least in part, to limit accumulation of this viral helicase in the nucleus in order to prevent its detrimental effect on cellular proliferation.

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Peled-Zehavi, Hadas, J. Andrew Berglund, Michael Rosbash, and Alan D. Frankel. "Recognition of RNA Branch Point Sequences by the KH Domain of Splicing Factor 1 (Mammalian Branch Point Binding Protein) in a Splicing Factor Complex." Molecular and Cellular Biology 21, no. 15 (August 1, 2001): 5232–41. http://dx.doi.org/10.1128/mcb.21.15.5232-5241.2001.

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ABSTRACT Mammalian splicing factor 1 (SF1; also mammalian branch point binding protein [mBBP]; hereafter SF1/mBBP) specifically recognizes the seven-nucleotide branch point sequence (BPS) located at 3′ splice sites and participates in the assembly of early spliceosomal complexes. SF1/mBBP utilizes a “maxi-K homology” (maxi-KH) domain for recognition of the single-stranded BPS and requires a cooperative interaction with splicing factor U2AF65 bound to an adjacent polypyrimidine tract (PPT) for high-affinity binding. To investigate how the KH domain of SF1/mBBP recognizes the BPS in conjunction with U2AF and possibly other proteins, we constructed a transcriptional reporter system utilizing human immunodeficiency virus type 1 Tat fusion proteins and examined the RNA-binding specificity of the complex using KH domain and RNA-binding site mutants. We first established that SF1/mBBP and U2AF cooperatively assemble in our reporter system at RNA sites composed of the BPS, PPT, and AG dinucleotide found at 3′ splice sites, with endogenous proteins assembled along with the Tat fusions. We next found that the activities of the Tat fusion proteins on different BPS variants correlated well with the known splicing efficiencies of the variants, supporting a model in which the SF1/mBBP-BPS interaction helps determine splicing efficiency prior to the U2 snRNP-BPS interaction. Finally, the likely RNA-binding surface of the maxi-KH domain was identified by mutagenesis and appears similar to that used by “simple” KH domains, involving residues from two putative α helices, a highly conserved loop, and parts of a β sheet. Using a homology model constructed from the cocrystal structure of a Nova KH domain-RNA complex (Lewis et al., Cell 100:323–332, 2000), we propose a plausible arrangement for SF1/mBBP-U2AF complexes assembled at 3′ splice sites.

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Paul, John H., Shannon J. Williamson, Amy Long, R. Nathan Authement, David John, Anca M. Segall, Forest L. Rohwer, Matthew Androlewicz, and Stacey Patterson. "Complete Genome Sequence of φHSIC, a Pseudotemperate Marine Phage of Listonella pelagia." Applied and Environmental Microbiology 71, no. 6 (June 2005): 3311–20. http://dx.doi.org/10.1128/aem.71.6.3311-3320.2005.

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ABSTRACT The genome for the marine pseudotemperate member of the Siphoviridae φHSIC has been sequenced using a combination of linker amplification library construction, restriction digest library construction, and primer walking. φHSIC enters into a pseudolysogenic relationship with its host, Listonella pelagia, characterized by sigmoidal growth curves producing >109 cells/ml and >1011 phage/ml. The genome (37,966 bp; G+C content, 44%) contained 47 putative open reading frames (ORFs), 17 of which had significant BLASTP hits in GenBank, including a β subunit of DNA polymerase III, a helicase, a helicase-like subunit of a resolvasome complex, a terminase, a tail tape measure protein, several phage-like structural proteins, and 1 ORF that may assist in host pathogenicity (an ADP ribosyltransferase). The genome was circularly permuted, with no physical ends detected by sequencing or restriction enzyme digestion analysis, and lacked a cos site. This evidence is consistent with a headful packaging mechanism similar to that of Salmonella phage P22 and Shigella phage Sf6. Because none of the phage-like ORFs were closely related to any existing phage sequences in GenBank (i.e., none more than 62% identical and most <25% identical at the amino acid level), φHSIC is unique among phages that have been sequenced to date. These results further emphasize the need to sequence phages from the marine environment, perhaps the largest reservoir of untapped genetic information.

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Müller, C., and P. Böttcher. "Darstellung und Kristallstruktur des Bis(diisobutylammonium)-heptasulfids [H2N(i-C4H9)2]2S7 / Synthesis and Crystal Structure of Bis(diisobutylammonium)-heptasulfide [H2N(i-C4H9)2]2S7." Zeitschrift für Naturforschung B 48, no. 12 (December 1, 1993): 1732–36. http://dx.doi.org/10.1515/znb-1993-1207.

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The reaction of diisobutylamine, H2S, and sulfur in a mixture of dimethylformamide, formamide, and ethanol yields orange crystals of bis(diisobutylammonium)-heptasulfide. The compound crystallizes in the centrosymmetric orthorhombic space group Pbca, the lattice constants are a = 11.234(4), b = 17.875(7), c = 27.009(10) Å. The S72-chain does not have the common helical all-trans-conformation, but a mixed conformation trans-cis-trans (sequence of the signs of torsion angles + + - - and - - + +).

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Gargantini, Pablo R., Marianela C. Serradell, Alessandro Torri, and Hugo D. Lujan. "Putative SF2 helicases of the early-branching eukaryote Giardia lamblia are involved in antigenic variation and parasite differentiation into cysts." BMC Microbiology 12, no. 1 (2012): 284. http://dx.doi.org/10.1186/1471-2180-12-284.

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Müller, C., and P. Böttcher. "Darstellung und Kristallstruktur des Bis(dicyclohexylammoniuni)-lieptasulfids [H2N(C6H11 )2]2S7/Preparation and Crystal Structure of Bis(dicyclohexylammonium )-heptasulfide [H2N(C6H11)2]2S7." Zeitschrift für Naturforschung B 48, no. 1 (January 1, 1993): 90–92. http://dx.doi.org/10.1515/znb-1993-0120.

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The reaction of dicyclohexylamine and sulphur (molar ratio 2:7) with H2S in a mixture of dimethylformamide and formamide yields red crystals of bis(dicyclohexylammonium)heptasulfide. The compound crystallizes in the centrosymmetric space group P21,/c, the lattice constants are a = 9.787(2) Å, b = 18.972(4) Å, c = 17.118(3) Å, β = 96,12(2)°. The S72- chain has not the common helical all-trans-conformation, but a mixed conformation trans-cis-trans (sequence of the signs of torsion angles ++ - - and - - ++).

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Zheng, Zheng, Minli Bao, Fengnian Wu, Christopher Van Horn, Jianchi Chen, and Xiaoling Deng. "A Type 3 Prophage of ‘Candidatus Liberibacter asiaticus’ Carrying a Restriction-Modification System." Phytopathology® 108, no. 4 (April 2018): 454–61. http://dx.doi.org/10.1094/phyto-08-17-0282-r.

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Prophages, the lysogenic form of bacterial phages, are important genetic entities of ‘Candidatus Liberibacter asiaticus’ (CLas), a nonculturable α-proteobacterium associated with citrus Huanglongbing. Two CLas prophages have been described, SC1 (NC_019549.1, Type 1) and SC2 (NC_019550.1, Type 2), which involve the lytic cycle and the lysogenic cycle, respectively. To explore the prophage repertoire, 523 CLas DNA samples extracted from leaf petioles of CLas-infected citrus were collected from southern China and surveyed for Type 1 and Type 2 prophages by specific PCR. Eighteen samples were found lacking both prophages. One sample, JXGC, sequenced using Illumina HiSeq, generated >100 million short sequence reads (150 bp per read). Read mapping to known prophage sequences showed a sequence coverage of 46% to SC1 and 50% to SC2. BLAST search using SC1 and SC2 as queries identified three contigs from the JXGC de novo assembly that form a circular P-JXGC-3 (31,449 bp), designated as a new Type 3 prophage. Chromosomal integration of P-JXGC-3 was detected to occur within a helicase gene, resulting in a duplication of this gene. P-JXGC-3 had 36 open reading frames (ORFs), 10 of which were not found in Type 1 or Type 2 prophages, including four genes that encoded a restriction-modification (R-M) system (hsdR, hsdS, hsdM1, and hsdM2). Typed by prophage-specific PCR, the CLas strains in southern China contained all combinations of the three prophage types with the exception of a Type 2−Type 3 combination, suggesting active ongoing prophage−phage interactions. Based on gene annotation, P-JXGC-3 is not capable of reproduction via the lytic cycle. The R-M system was speculated to play a role against Type 1 prophage−phage invasion.

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George, Biju, Rajrani Ruhel, Mohit Mazumder, Veerendra Kumar Sharma, Swatantra Kumar Jain, Samudrala Gourinath, and Supriya Chakraborty. "Mutational analysis of the helicase domain of a replication initiator protein reveals critical roles of Lys 272 of the B′ motif and Lys 289 of the β-hairpin loop in geminivirus replication." Journal of General Virology 95, no. 7 (July 1, 2014): 1591–602. http://dx.doi.org/10.1099/vir.0.064923-0.

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Replication initiator protein (Rep) is indispensable for rolling-circle replication of geminiviruses, a group of plant-infecting circular ssDNA viruses. However, the mechanism of DNA unwinding by circular ssDNA virus-encoded helicases is unknown. To understand geminivirus Rep function, we compared the sequence and secondary structure of Rep with those of bovine papillomavirus E1 and employed charged residue-to-alanine scanning mutagenesis to generate a set of single-substitution mutants in Walker A (K227), in Walker B (D261, 262), and within or adjacent to the B′ motif (K272, K286 and K289). All mutants were asymptomatic and viral accumulation could not be detected by Southern blotting in both tomato and N. benthamiana plants. Furthermore, the K272 and K289 mutants were deficient in DNA binding and unwinding. Biochemical studies and modelling data based on comparisons with the known structures of SF3 helicases suggest that the conserved lysine (K289) located in a predicted β-hairpin loop may interact with ssDNA, while lysine 272 in the B′ motif (K272) located on the outer surface of the protein is presumably involved in coupling ATP-induced conformational changes to DNA binding. To the best of our knowledge, this is the first time that the roles of the B′ motif and the adjacent β-hairpin loop in geminivirus replication have been elucidated.

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Vasilevskaya, Ekaterina Romanovna, and Anastasia Gennadievna Akhremko. "Proteomic study of pig’s spleen." Potravinarstvo Slovak Journal of Food Sciences 13, no. 1 (May 28, 2019): 314–17. http://dx.doi.org/10.5219/1093.

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This work is devoted to pig spleen proteome study. Spleens were taken from Duroc pigs (females, 145 – 160 days old) and typical two-dimensional electrophoregrams were obtained. On proteomic maps after visualization and image analysis there were detected 600 fractions, including organ-specific proteins – 3 62 fractions. Among the identified constitutive fractions, the highest expression was observed (Vol spots more than 3.0E + 07) four protein spots S1, S9, S12 and S21, which are supposedly Annexin A1 (MW 38.76 kDa), Ectonucleoside triphosphate diphosphohydrolase 1 (MW 57.75 kDa) Pro-cathepsin H CD59 (MW 37.45 kDa) and glycoprotein (MW 13.79 kDa), respectively. Obtained electrophoregrams analysis using information resources made it possible to identify different active compounds in spleen with various functions, mainly immunoregulatory – glycoprotein CD59 (Mm 13.79 kDa) and ATP-dependent RNA helicase (Mm 107.58 kDa); the intensely expressed LIM-domain of the actin-binding protein (Mm 83.99 kDa). The results obtained are a prospect for immunomodulating biologic development based on animal raw materials for farm animals.

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