Image Helicase.png thumb 220px Structure of E. coli helicase RuvA Helicases are a class of enzyme s vital ... Real time observation of bacteriophage T4 gp41 helicase reveals an unwinding mechanism journal PNAS ... Single molecule studies reveal dynamics of DNA unwinding by the ring shaped t7 helicase journal Cell ... ref In the latter case, the helicase acts comparably to an active motor, unwinding and translocating ... physorg1 Defects in the gene that codes helicase cause Werner syndrome , a disorder characterized by the appearance ... of the amino acid sequence is related to the specific features of each helicase. Based on the presence of defined helicase motifs, it is possible to attribute a putative helicase activity to a given protein, though the presence of a motif does not confirm the protein as a helicase. Conserved ... and the form of helicase motifs, helicases have been separated in 4 superfamilies and 2 smaller ... from superfamily 1. This helicase has multiple roles at different stages of viral RNA replication, as dissected ... X author Garcia JA, Kaariainen L, Gomez de cedron M, Ehsani N, Mikkola ML title RNA helicase activity ... year 1999 pmid 10217401 ref Superfamily II RecQ helicase RecQ E. coli, DNA repair , eIF4A saccharomyces ... pubmed DocSum RNA Translocation and Unwinding Mechanism of HCV NS3 Helicase and its Coordination ... on the host cell machinery to replicate. SF3 helicase in small viruses is associated with an origin binding domain. By pairing a domain that recognises the ori with a helicase, the virus can ..., and the viral DNA is replicated. DnaB like family dnaB helicase dnaB E. coli , replication , gp41 bacteriophage T4 , DNA replication , T7 DNA Helicase T7gp4 bacteriophage T7, DNA replication . Rho ... families. RNA Helicases RNA Helicases and DNA Helicases can be found together in all the Helicase ... 2010 ref However, not all RNA Helicases exhibit helicase activity as defined by enzymatic function, i.e., proteins of the Swi Snf family. Although these proteins carry the typical helicase motifs, hydrolize ... more details
lowercase title Cleanup date September 2008 Infobox protein Name Replicative DNA helicase image width caption Symbol dnaB AltSymbols CAS number CAS supplemental DrugBank EntrezGene 948555 PDB RefSeq UniProt P0ACB0 ECnumber 3.6.1. Chromosome dnaB helicase is an enzyme in bacteria which opens the replication fork during DNA replication . Initially when DnaB binds to dnaA , it is associated with dnaC , a negative regulator. After DnaC dissociates, DnaB binds dnaG . In eukaryotes, helicase function is provided by the T antigen . The DnaB helicase is the product of the dnaB gene. The helicase enzyme that is produced is a hexamer in E. coli , as well as in many other bacteria. The energy for DnaB activity is provided by NTP hydrolysis. Mechanical energy moves the DnaB into the replication fork, physically splitting it in half E. coli dnaB In E. coli , dnaB is a hexameric protein of six 471 residue subunits, which form a ring shaped structure with threefold symmetry. During DNA replication, the lagging strand of DNA binds in the central channel of dnaB, and the second DNA strand is excluded. The binding of dNTPs causes a conformational change which allows the dnaB to translocate along the DNA, thus mechanically forcing the separation of the DNA strands. External links MeshName DnaB Helicases hydrolase stub DNA replication Category DNA replication Category EC 3.6.1 ja DnaB ru DnaB ... more details
PBB geneid 1660 ATP dependent RNA helicase A is an enzyme that in humans is encoded by the DHX9 gene . ref name pmid8344961 cite journal author Lee CG, Hurwitz J title Human RNA helicase A is homologous ... Domain structure of human nuclear DNA helicase II RNA helicase A journal J Biol Chem volume 272 ... and division. This gene encodes a DEAD box protein with RNA helicase activity. It may participate ... domain and an RGG box. The RNA binding domains and RGG box influence and regulate RNA helicase activity ... month Jul. title Sam68, RNA helicase A and Tap cooperate in the post transcriptional regulation of human ... month Aug. title Mapping the functional domains of HAP95, a protein that binds RNA helicase A and activates ... T R, Wong Staal F year 2000 month Jul. title A novel shuttle protein binds to RNA helicase A and activates ... Oct. title Specific interaction between RNA helicase A and Tap, two cellular proteins that bind to the constitutive .... title RNA helicase A interacts with nuclear factor kappaB p65 and functions as a transcriptional .... title Arginine methylation of RNA helicase a determines its subcellular localization journal J. Biol ... of RNA helicase A causes inhibition of endogenous BRCA1 function and defects in ploidy and cytokinesis ... Jul. title BRCA1 protein is linked to the RNA polymerase II holoenzyme complex via RNA helicase A journal ... citations cite journal author Lee CG, Hurwitz J title A new RNA helicase isolated from HeLa cells ... D, Greenberg AH title Leukophysin an RNA helicase A related molecule identified in cytotoxic ... doi cite journal author Nakajima T, Uchida C, Anderson SF, et al. title RNA helicase A mediates ... and genomic DNA encoding mouse RNA helicase A. journal Genomics volume 47 issue 3 pages 365 71 year ... T, et al. title BRCA1 protein is linked to the RNA polymerase II holoenzyme complex via RNA helicase ... author Lee CG, da Costa Soares V, Newberger C, et al. title RNA helicase A is essential for normal ... al. title A role for RNA helicase A in post transcriptional regulation of HIV type 1. journal Proc ... more details
ATP dependent helicase Werner syndrome caption image width HGNCid 12791 Symbol Werner syndrome ATP dependent helicase WRN AltSymbols EntrezGene 7486 OMIM 604611 RefSeq NM 000553 UniProt Q14191 PDB ECnumber Chromosome 8 Arm p Band LocusSupplementaryData RecQ helicase is a family of helicase enzyme ... The function of RecQ helicase gene family especially BLM in DNA recombination and joining journal ... members share three regions of conserved protein sequence referred to as the N terminus N terminal Helicase middle RecQ conserved RecQ Ct and C terminus C terminal Helicase and RNase D C terminal HRDC domains. The removal of the N terminal residues Helicase and, RecQ Ct domains impairs both helicase ... journal author Hanada K, Hickson ID title Molecular genetics of RecQ helicase disorders journal Cell ... of RecQ helicase with topoisomerase III at the N terminal region is involved in the suppression ... BLM gene encodes a RecQ Helicase , description of the gene Acid anhydride hydrolases Category EC 3.6.1 ... more details
Orphan date April 2011 infobox biodatabase title RNA helicase database. logo File Database.png description RNA helicase database. scope organism center Case Western Reserve University laboratory Department of Biochemistry, Center for RNA Molecular Biology author Anja Jankowsky pmid Jankowsky & al. 2011 ref name pmid21112871 released 2010 standard format url http www.rnahelicase.org www.rnahelicase.org download webservice sql sparql webapp standalone license versioning frequency curation bookmark version The The RNA helicase database stores data sequence, structures... about RNA helicase s. ref name pmid21112871 cite journal quotes yes last Jankowsky first Anja authorlink coauthors Guenther Ulf Peter, Jankowsky Eckhard year 2011 month Jan title The RNA helicase database journal Nucleic Acids Res. volume 39 issue Database issue pages D338 41 publisher location England issn pmid 21112871 doi 10.1093 nar gkq1002 bibcode oclc id url pmc 3013637 language eng format accessdate laysummary laysource laydate quote ref References references See also Helicase External links http www.rnahelicase.org www.rnahelicase.org Biodatabase stub Category Biological databases Category RNA Category RNA binding proteins not sure ... more details
T7 DNA Helicase is a hexameric motor protein that uses energy from Thymidine triphosphate dTTP hydrolysis to process unidirectionally along single stranded DNA , separating the two strands as it progresses. Crystal Structure The crystal structure was solved to 3.0 resolution in 2000, ref cite journal doi 10.1016 S0092 8674 00 80871 5 author Singleton MR, Sawaya MR, Ellenberger T, Wigley DB title Crystal structure of T7 gene 4 ring helicase indicates a mechanism for sequential hydrolysis of nucleotides journal Cell volume 101 issue 6 pages 589 600 year 2000 month June pmid 10892646 url http linkinghub.elsevier.com retrieve pii S0092 8674 00 80871 5 ref as shown in the figure. In A , notice that the separate subunits appear to be anchored through interactions between an alpha helix and an adjacent subunit. In B , there are six sets of three loops. The red loop, known as loop II, contains three lysine residues and is thought to be involved in binding the ssDNA that is fed through the center of the enzyme. Mechanism of Sequential dTTP Hydrolysis Crampton et al. have proposed a mechanism for the ssDNA dependent hydrolysis of dTTP by T7 DNA Helicase as shown in the figure below. ref cite journal author Crampton DJ, Mukherjee S, Richardson CC title DNA induced switch from independent to sequential dTTP hydrolysis in the bacteriophage T7 DNA helicase journal Mol. Cell volume 21 issue 2 pages 165 74 year 2006 month January pmid 16427007 doi 10.1016 j.molcel.2005.11.027 url http linkinghub.elsevier.com retrieve pii S1097 2765 05 01815 0 ref In their model, protein loops located on each hexameric subunit, each of which contain three lysine residues, sequentially interact with the negatively ... of the T7 DNA helicase journal Nat. Struct. Biol. volume 3 issue 9 pages 740 3 year 1996 month September pmid 8784344 ref . References reflist See also Helicase External links MeshName T7 DNA Primase Helicase Protein DNA replication Category Molecular biology Category Enzymes Category DNA replication ... more details
Pfam box Symbol DEAD Name DEAD DEAH box helicase image PDB 1qva EBI.jpg width caption Structure of the amino terminal domain of yeast initiation factor 4A. ref name pmid10606264 cite journal author Johnson ER, McKay DB title Crystallographic structure of the amino terminal domain of yeast initiation factor 4A, a representative DEAD box RNA helicase journal RNA volume 5 issue 12 pages 1526 34 year 1999 month December pmid 10606264 pmc 1369875 doi 10.1017 S1355838299991410 url ref Pfam PF00270 Pfam clan CL0023 InterPro IPR011545 SMART PROSITE PDOC00039 SCOP 1qva TCDB OPM family OPM protein PDB PDB2 1fuk , PDB2 1fuu , PDB2 1gku , PDB2 1gl9 , PDB2 1gm5 , PDB2 1hv8 , PDB2 1oyw , PDB2 1oyy , PDB2 1q0u , PDB2 1qde , PDB2 1qva , PDB2 1t5i , PDB2 1t6n , PDB2 1vec , PDB2 1xti , PDB2 1xtj , PDB2 1xtk , PDB2 2g9n , PDB2 2j0u The DEAD DEAH box helicases are a family of protein s whose purpose is to unwind nucleic acid s. The DEAD box helicase s are involved in various aspects of RNA metabolism, including nuclear transcription genetics transcription , pre mRNA splicing, ribosome biogenesis , nucleocytoplasmic transport, translation, RNA decay and organellar gene expression. ref name pmid10322435 cite journal author de la Cruz J, Kressler D, Linder P title Unwinding RNA in Saccharomyces cerevisiae DEAD box proteins and related families journal Trends Biochem. Sci. volume 24 issue 5 pages 192 8 year 1999 month May pmid 10322435 doi 10.1016 S0968 0004 99 01376 6 url http linkinghub.elsevier.com retrieve pii S0968 0004 99 01376 6 issn ref ref name pmid9862990 cite journal author Aubourg S, Kreis M, Lecharny A title The DEAD box RNA helicase family in Arabidopsis thaliana journal Nucleic Acids Res. volume 27 issue 2 pages 628 36 year 1999 month January pmid 9862990 pmc 148225 doi 10.1093 nar 27.2.628 url http nar.oxfordjournals.org cgi pmidlookup?view long&pmid 9862990 issn ref References Reflist InterPro content IPR011545 Category Protein domains ... more details
Helicase dependent amplification HDA is a method for in vitro DNA amplification like the polymerase chain reaction PCR , but that works at constant temperature. Introduction The polymerase chain reaction is the most widely used method for in vitro DNA amplification for purposes of molecular biology and biomedical research. ref cite journal journal Science volume 239 issue 4839 pages 487 491 year 1988 author Saiki RK et al. title Primer directed enzymatic amplification of DNA with a thermostable DNA polymerase pmid 2448875 doi 10.1126 science.2448875 ref This process involves the separation of the double stranded DNA in high heat into single strands the denaturation step, typically achieved at 95 97 sup o sup C , annealing of the primers to the single stranded DNA the annealing step and copying the single strands to create new double stranded DNA the extension step that requires the DNA polymerase requires the reaction to be done in a thermal cycler . These bench top machines are large, expensive and costly to run and maintain, limiting the potential applications of DNA amplification in situations outside the laboratory e.g., in the identification of potentially hazardous micro organisms at the scene of investigation, or at the point of care of a patient . In vivo , DNA is replicated by DNA polymerases with various accessory proteins, including a DNA helicase that acts to separate the DNA by unwinding the DNA double helix. ref cite book author Kornberg A, Baker T year 1992 title ... from this concept, using a helicase an enzyme to denature the DNA. Methodology Strands of double stranded DNA are first separated by a DNA helicase and coated by single stranded DNA ssDNA binding ... H. title Helicase dependent isothermal DNA amplification pmid 15247927 doi 10.1038 sj.embor.7400200 ..., Kong H, Tang YW, Tang W. title Application of isothermal helicase dependent amplification with a disposable ... http www.biohelix.com Biohelix Corporation official website References references DEFAULTSORT Helicase ... more details
between WRN, the helicase exonuclease defective in progeroid Werner s syndrome, and an essential ... no update citations no DEFAULTSORT Werner Syndrome Atp Dependent Helicase Category Genes es WRN ... more details
PcrA , standing for plasmid copy reduced is a helicase that was originally discovered in a screen for chromosomally encoded genes that are affected in plasmid rolling circle replication in the Gram positive pathogen Staphylococcus aureus . Biological functions Genetic and biochemical studies have shown that the helicase is essential for plasmid rolling circle replication and repair of DNA damage caused by exposure to ultraviolet radiation. It catalyzes the unwinding of double stranded plasmid DNA that has been nicked at the replication origin by the replication initiation protein. Genetic and biochemical studies have also shown that the helicase plays an important role in cell survival by regulating the levels of RecA mediated recombination in Gram positive bacteria. Biochemical properties The helicase is a monomeric translocase and utilizes ATP to unwind DNA. The preferred substrates are single stranded DNA containing 3 overhangs. The processivity of PcrA is increased in the presence of plasmid replication initiation protein. Crystal Structure The structure of the helicase has been solved at high resolution and indicates inchworming as the mechanism of translocation on single stranded DNA. A Mexican wave model has been proposed based on the changes in conformation of the helicase observed in the product versus substrate complex. Classification PcrA belongs to the SF1 superfamily of helicases, which also include the E. coli helicases UvrD and Rep and the eukaryotic helicase Srs2 ... E, Rose M, Entian KD, McGovern S, Ehrlich SD, Bruand C. PcrA is an essential DNA helicase of Bacillus ..., Munshi R, Khan SA. Biochemical characterization of the Staphylococcus aureus PcrA helicase and its ... 19. Anand SP, Zheng H, Bianco PR, Leuba SH, Khan SA. DNA helicase activity of PcrA is not required ... DNA helicase. Nucleic Acids Res. 1999 Mar 15 27 6 1421 8. Velankar SS, Soultanas P, Dillingham MS, Subramanya HS, Wigley DB. Crystal structures of complexes of PcrA DNA helicase with a DNA substrate ... more details
Sgs1 , also known as small growth suppressor 1 , ref cite journal title The yeast type I topoisomerase Top3 interacts with Sgs1, a DNA helicase homolog a potential eukaryotic reverse gyrase last Gangloff first S et al journal Molecular and Cellular Biology year 1994 month December volume 14 issue 12 page 8391 8398 pmc 359378 pmid 7969174 ref is a DNA helicase protein found in Saccharomyces cerevisiae . It is a Homology biology Homology of sequences in genetics homolog of the bacterial RecQ helicase. Like the other members of the RecQ helicase family, Sgs1 is important for DNA repair . In particular, Sgs1 collaborates with other proteins to repair double strand breaks during Homologous recombination In eukaryotes homologous recombination in eukaryotes. ref cite journal title Sae2, Exo1 and Sgs1 collaborate in DNA double strand break processing last1 Mimitou first1 EP last2 Symington first2 LS date 9 October 2008 volume 455 issue 7214 pages 770 774 doi 10.1038 nature07312 pmid 18806779 ref References Reflist Category DNA repair ... more details
lowercase title DnaG Infobox protein Name DNA primase image width caption Symbol dnaG AltSymbols dnaP CAS number CAS supplemental DrugBank EntrezGene 947570 PDB RefSeq UniProt P0ABS5 ECnumber 2.7.7.7 DnaG is a bacterial primase which synthesizes short RNA oligonucleotides during DNA replication. These RNA oligonucleotides serve as primers for DNA synthesis by bacterial DNA polymerase Pol III. On one of the two parental strands, called the lagging strand, the primase makes a primer every few kilobases. These primers serve a substrates for synthesis of Okazaki fragments. DnaG associates with bacterial replicative helicase DnaB to perform its primase activity. About three DnaG primase proteins associate with each DnaB helicase. External links MeshName dnaG protein, E coli MeshName DnaG Primase enzyme stub DNA replication Category DNA replication ru DnaG ... more details
The degradosome is a multi protein complex present in most bacteria that is involved in the processing of ribosomal RNA and the degradation of messenger RNA . It contains the proteins RNA helicase RNA helicase B , RNase RNase E and Polynucleotide phosphorylase . ref cite journal author Carpousis AJ title The Escherichia coli RNA degradosome structure, function and relationship in other ribonucleolytic multienzyme complexes journal Biochem. Soc. Trans. volume 30 issue 2 pages 150 5 year 2002 pmid 12035760 url http www.biochemsoctrans.org bst 030 0150 bst0300150.htm doi 10.1042 BST0300150 ref See also Exosome complex Proteasome References references Category Protein complexes Category Ribonucleases Enzyme stub ca Degradosoma es Degradosoma de Degradosom zh ... more details
lowercase title Infobox protein Name Chromosomal replication initiator protein dnaA image width caption Symbol dnaA AltSymbols CAS number CAS supplemental DrugBank EntrezGene 948217 PDB RefSeq UniProt P03004 ECnumber Chromosome dnaA is a replication initiation factor which promotes the unwinding or Denaturation biochemistry denaturation of DNA at oriC around 240 base pair bp in Escherichia coli , during DNA replication in prokaryotes . The formation of the oriC DnaA complex and DNA unwinding requires ATP hydrolysis ref 1 . The oriC site in E. coli has three adenosine A threonine T rich 13 base pair regions DNA unwinding element DUE s elements followed by five 9 bp regions. Around 10 dnaA molecule s bind to the 9 bp regions, which wrap around the proteins causing the DNA at the AT rich region to unwind. The denatured AT rich region allows for the recruitment of DnaB helicase complexes with DnaC helicase loader . DnaC helps the helicase to bind to and to properly accommodate the ssDNA at the 13 bp region, this is accomplished by Adenosine triphosphate ATP hydrolysis after which DnaC is released. Single strand binding protein Single strand binding protein s SSBs stabilize the single DNA strands in order to maintain the replication bubble . DnaB is a 5 3 helicase, so it travels on the lagging strand . It associates with DnaG a primase to form the only Primer molecular biology primer for the leading strand and to add RNA primers on the lagging strand. The interaction between DnaG and DnaB is necessary to control the longitude of Okazaki fragments on the lagging strand. DNA polymerase III is then able to start DNA replication . External links MeshName DnaA protein, Bacteria References div class references small Voet, Donald Voet, Judith Pratt, Charlotte 2001 . Fundamentals of Biochemistry . Wiley. Nelson, David L. Cox, Michael M. 2008 . Principles of Biochemistry . Freeman. div genetics stub biochem stub DNA replication Category Biomolecules Category DNA replication it Dn ... more details
Orphan date February 2009 PBB geneid 5965 ATP dependent DNA helicase Q1 is an enzyme that in humans is encoded by the RECQL gene . ref name pmid7527136 cite journal author Seki M, Miyazawa H, Tada S, Yanagisawa J, Yamaoka T, Hoshino S, Ozawa K, Eki T, Nogami M, Okumura K, et al. title Molecular cloning of cDNA encoding human DNA helicase Q1 which has homology to Escherichia coli Rec Q helicase and localization of the gene at chromosome 12p12 journal Nucleic Acids Res volume 22 issue 22 pages 4566 73 year 1995 month Jan pmid 7527136 pmc 308502 doi 10.1093 nar 22.22.4566 ref ref name pmid7961977 cite journal author Puranam KL, Blackshear PJ title Cloning and characterization of RECQL, a potential human homologue of the Escherichia coli DNA helicase RecQ journal J Biol Chem volume 269 issue 47 ... RECQL RecQ protein like DNA helicase Q1 like url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ... text The protein encoded by this gene is a member of the RecQ DNA helicase family. DNA helicases are enzymes ... to malignancy and chromosomal instability. The biological function of this helicase has not yet ... protein like DNA helicase Q1 like url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch ... homologue, Qip1 discrimination of Qip1 and Rch1 from hSrp1 by their ability to interact with DNA helicase ... DNA helicase RECQL and its mouse homologue. journal Genomics volume 26 issue 3 pages 595 8 year ... T, et al. title Purification of two DNA dependent adenosinetriphosphatases having DNA helicase activity ... and Rch1 from hSrp1 by their ability to interact with DNA helicase Q1 RecQL. journal Biochem. Biophys ... cite journal author Zhang AH, Xi X title Molecular cloning of a splicing variant of human RECQL helicase ... of the DNA unwinding activity of human RECQ1, a helicase specifically stimulated by human ... of the unwinding activity of the dimeric RECQ1 helicase in the presence of human replication protein ... pmc 528928 cite journal author Doherty KM, Sharma S, Uzdilla LA, et al. title RECQ1 helicase interacts ... more details
orphan date August 2010 RHAU RNA Helicase associated with AU rich element, also known as DHX36 or G4R1 is a 114 kDa human RNA helicase of the DEAH box family of helicases encoded by the DHX36 gene. ref cite journal doi 10.1016 S0888 7543 03 00049 1 author Abdelhaleem M, Maltais L, Wain H title The human DDX and DHX gene families of putative RNA helicases journal Genomics volume 81 issue 6 pages 618 22 year 2003 month June pmid 12782131 url http linkinghub.elsevier.com retrieve pii S0888754303000491 ref Structure File RHAU domain architecture 02.svg thumb 600xpx Schematic representation of RHAU protein Structurally, RHAU is a 1008 amino acid long modular protein. It consists of a 440 amino acid helicase core comprising all signature motifs of the DEAH box family of helicases with N and C terminal flanking regions of 180 and 380 amino acids, respectively. Like all the DEAH box proteins, the helicase associated domain is located adjacent to the helicase core region and occupies 75 of the C terminal region. Function RHAU exhibits a unique ATP dependent G quadruplex guanine quadruplex G4 resolvase activity and specificity for its substrate in vitro . ref cite journal author Vaughn JP, Creacy SD, Routh ED, et al. title The DEXH protein product of the DHX36 gene is the major source of tetramolecular quadruplex G4 DNA resolving activity in HeLa cell lysates journal The Journal of Biological Chemistry volume 280 issue 46 pages 38117 20 year 2005 month November pmid 16150737 doi 10.1074 jbc.C500348200 ref ref cite journal author Creacy SD, Routh ED, Iwamoto F, Nagamine Y, Akman SA, Vaughn JP title G4 resolvase 1 binds both DNA and RNA tetramolecular quadruplex with high affinity and is the major source of tetramolecular quadruplex G4 DNA and G4 RNA resolving activity in HeLa cell ... N, Iwamoto F, Fujiki Y, Nagamine Y title Recruitment of the RNA helicase RHAU to stress granules via ... functional domains of the RNA helicase RHAU involved in subcellular localization and RNA interaction ... more details
mechanisms differ between different bacteria and viruses where the primase covalently link to helicase ... HSV 1 , primase can form complexes with helicase. ref name cav cite journal author Cavanaugh, Nisha ... Simplex Virus 1 Primase Helicase Complex and Either Herpes DNA Polymerase or Human DNA Polymerase ... ref The primase helicase complex is used to unwind dsDNA and synthesizes the lagging strand using RNA ... Helicase binding domain of Escherichia coli primase http proteopedia.org wiki index.php 2r6c Proteopedia Complex between the DnaB helicase and the DnaG primase References Reflist Polymerases ... more details
HDA may stand for HDA, the ICAO airline code for Dragonair airline Dragonair Hard Dance Awards Head and Disk Assembly of a Winchester sealed hard disk drive Helicase dependent amplification , a technique to copy DNA Hidden Falls High density amorphous ice , a phase of water How to Destroy Angels band , a 2010s band featuring Trent Reznor Technology and computing tt Device file system Naming conventions dev hda tt , on linux the master device on the first AT Attachment channel Intel High Definition Audio High Definition Audio See also dev hda disambig de HDA it HDA ja HDA ... more details
Refimprove date December 2009 In molecular biology, a primosome is a protein complex responsible for creating RNA primers on single stranded DNA during DNA replication . The primosome consists of seven proteins DnaG primase , DnaB helicase , DnaC helicase assistant, DnaT, PriA , Pri B , and PriC . The primosome is utilized once on the leading strand of DNA and repeatedly, initiating each Okazaki fragment , on the lagging DNA strand. Initially the complex formed by PriA, PriB, and PriC binds to DNA. Then the DnaB DnaC helicase complex attaches along with DnaT. This structure is referred to as the pre primosome. Finally, DnaG will bind to the pre primosome forming a complete primosome. The primosome attaches 1 10 RNA nucleotides to the single stranded DNA creating a DNA RNA hybrid. This sequence of RNA is used as a primer to initiate DNA polymerase III . The RNA bases are ultimately replaced with DNA bases by RNase H nuclease eukaryotes or DNA polymerase I nuclease prokaryotes . DNA Ligase then acts to join the two ends together. Assembly of the Escherichia coli primosome requires six proteins, PriA, PriB, PriC, DnaB, DnaC, and DnaT, acting at a primosome assembly site pas on an SSBcoated single stranded 8s DNA. Assembly is initiated by interactions of PriA and PriB with ssDNA and the pas. PriC, DnaB, DnaC, and DnaT then act on the PriAPriB DNA complex to yield the primosome. ref Assembly of the primosome of DNA replication in Escherichia coli. http www.ncbi.nlm.nih.gov pubmed 8366072 ref Primosomes are nucleoproteins assemblies that activate DNA replication forks. Their primary role is to recruit the replicative helicase onto single stranded DNA. The replication restart primosome, defined in Escherichia coli, is involved in the reactivation of arrested replication forks. Binding of the PriA protein to forked DNA triggers its assembly. PriA is conserved in bacteria, but its primosomal partners are not. In Bacillus subtilis, genetic analysis has revealed three primosom ... more details
Orphan date September 2010 Unreferenced date April 2010 Very short patch VSP repair is a DNA repair system that removes GT mismatches created by the deamination of 5 methylcytosine to thymine . This system exists because the glycosylases which normally target deaminated bases cannot target thymine it being one of the regular four bases in DNA . The components of the system are MutS, which binds to the GT mismatch, the Vsr endonuclease, which cuts the DNA, and MutL, which recruits the UvrD helicase. Category DNA repair genetics stub DNA repair ... more details
Cleanup date December 2009 Dda short for DNA dependent ATPase also known as Dda helicase and Dda DNA helicase is the 439 amino acid 49,897 atomic mass unit protein coded by the Dda gene of the bacteriophage T4 phage , a virus that infects enterobacteria . Biochemistry Dda is a molecular motor , specifically a helicase that moves in the 5 end to 3 direction along a nucleic acid phosphodiester bond phosphodiester backbone , separating two annealed nucleic acid strands, using the free energy released by the hydrolysis of adenosine triphosphate . The National Center for Biotechnology Information NCBI Reference Sequence accession number is NP 049632. Molecular Biology Dda is involved in the initiation of T4 DNA replication and DNA recombination. Citation needed date December 2009 Genetics The Dda gene is 31,219 base pair long. The GenBank accession number is AAD4255. The coding strand see also sense strand begins in base number 9,410 and ends in base numer 10,729. ref name ncbi http www.ncbi.nlm.nih.gov nuccore NC 000866.4 ?from 9410&to 10729&strand true&report fasta ref ref http www.uniprot.org uniprot P32270 ref Cellular Biology Dda is toxic to cells at elevated levels. Citation needed date December 2009 See also Enzymes br Motor proteins br Transcription genetics References references External links http www.ncbi.nlm.nih.gov National Center for Biotechnology Access to biomedical and genomic information via the National Library of Medicine NLM at the National Institutes of Health NIH . Categories Category Molecular biology protein stub ... more details
PBB geneid 64135 Interferon induced helicase C domain containing protein 1 is an enzyme that in humans is encoded by the IFIH1 gene . ref name entrez cite web title Entrez Gene IFIH1 interferon induced with helicase C domain 1 url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 64135 accessdate ref The PBB Summary template is automatically maintained by Protein Box Bot. See Template PBB Controls to Stop updates. PBB Summary section title summary text DEAD box proteins, characterized by the conserved motif Asp Glu Ala Asp DEAD , are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Based on their distribution patterns, some members of this family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. This gene encodes a DEAD box protein that is upregulated in response to treatment with beta interferon IFNB and a protein kinase C activating ... name entrez cite web title Entrez Gene IFIH1 interferon induced with helicase C domain 1 url http ..., Gopalkrishnan RV, Wu Q, et al. title mda 5 An interferon inducible putative RNA helicase with double ... of Helicard, a CARD containing helicase cleaved during apoptosis, accelerates DNA degradation. journal ... helicase, RH116, differentially regulates cell growth, programmed cell death and human immunodeficiency ... the IFN inducible RNA helicase, mda 5, and inhibit its activation of the IFN beta promoter. journal ... locus in the interferon induced helicase IFIH1 region. journal Nat. Genet. volume 38 issue 6 ... D, et al. title The interferon inducible RNA helicase, mda 5, is involved in measles virus induced ..., Montgomery DS, Dickson MC, et al. title The interferon induced with helicase domain 1 A946T polymorphism ... J, Owen CJ, et al. title Genomic polymorphism at the interferon induced helicase IFIH1 locus contributes ... more details
Image DNA replication en.svg thumb 300px right A representation of the structures of the replisome during DNA replication The replisome is a complex molecular machine that carries out replication of DNA . It is made up of a number of subcomponents that each provide a specific function during the process of replication. Major Components While the replisome acts as a singular machine, its subcomponents are the complexes that perform the specific functions of replication. Helicase Helicase is an enzyme which breaks H bonds between the two strands of DNA. Its doughnut like structure wraps around DNA and separates the strands ahead of DNA synthesis. As helicase unwinds the double helix, it causes the helix to form supercoils in other areas of the DNA. In eukaryotes, the Mcm2 7 complex acts as a helicase, though which subunits are required for helicase activity is not entirely clear. ref http www.ncbi.nlm.nih.gov pubmed 18657510 ref This helicase translocates in the same direction as the DNA polymerase 3 to 5 with respect to the template strand . In prokaryotic systems, the helicases are better identified and include dnaB , which moves 5 to 3 on the strand opposite the DNA polymerase. Gyrase Gyrase a form of Topoisomerase relaxes and undoes the supercoiling caused by helicase. It does this by cutting the DNA strands, allowing it to rotate and release the supercoil, and then rejoining the strands. Gyrase is most commonly found upstream of the replication fork, where the supercoils form. Primase Primase adds complementary RNA primers to a DNA strand to begin Okazaki fragments . These primers are approximately 10 base pairs long and are at the 5 end of the okazaki fragment. Additionally, because DNA Polymerase can continue, but not begin, a strand, Primase must begin the leading strand as well. DNA polymerase III holoenzyme DNA polymerase III DNA pol III holoenzyme contains two catalytic cores one for replication of the leading strand and one for the lagging strand. DNA pol ... more details
Wikify date February 2011 PBB geneid 1663 Probable ATP dependent RNA helicase DDX11 is an enzyme that in humans is encoded by the DDX11 gene . ref name entrez cite web title Entrez Gene DDX11 DEAD H Asp Glu Ala Asp His box polypeptide 11 CHL1 like helicase homolog, S. cerevisiae url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 1663 accessdate ref The PBB Summary template is automatically maintained by Protein Box Bot. See Template PBB Controls to Stop updates. PBB Summary section title summary text DEAD box proteins, characterized by the conserved motif Asp Glu Ala Asp DEAD , are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Based on their distribution patterns, some members of this family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. This gene encodes a DEAD box protein, which is an enzyme that possesses both ATPase and DNA helicase activities. This gene is a homolog of the yeast CHL1 gene, and may function to maintain chromosome transmission fidelity and genome stability. Alternative splicing results in multiple transcript variants encoding distinct isoforms. ref name entrez cite web title Entrez Gene DDX11 DEAD H Asp Glu Ala Asp His box polypeptide 11 CHL1 like helicase homolog, S. cerevisiae url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 1663 accessdate ref References reflist Further reading refbegin 2 PBB Further reading citations cite journal author Baens M, Aerssens ... JM title Localization of chi1 related helicase genes to human chromosome regions 12p11 and 12p13 similarity ... of the enzymatic activity of hChlR1, a novel human DNA helicase. journal Nucleic Acids Res. volume ... J, Wang X, et al. title The DNA helicase ChlR1 is required for sister chromatid cohesion in mammalian ... more details
PBB geneid 1655 Probable ATP dependent RNA helicase DDX5 also known as DEAD box protein 5 or RNA helicase p68 is an enzyme that in humans is encoded by the DDX5 gene . ref name entrez cite web title Entrez Gene DDX5 DEAD Asp Glu Ala Asp box polypeptide 5 url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 1655 accessdate ref Function DEAD box proteins, characterized by the conserved motif Asp Glu Ala Asp DEAD , are putative RNA helicase s. They are implicated in a number of cellular processes involving alteration of RNA secondary structure, such as translation initiation ... RNA helicase journal J. Biol. Chem. volume 276 issue 20 pages 17448 54 year 2001 month May pmid 11279182 ... url issn ref DHX9 RNA helicase A , ref name pmid18005418 cite journal author Wilson BJ, Gigu re ... Purification and identification of p68 RNA helicase acting as a transcriptional coactivator specific ... cite journal author Rossow KL, Janknecht R title Synergism between p68 RNA helicase and the transcriptional ... RNA helicase p68 interacts with the nucleolar protein fibrillarin and colocalizes specifically in nascent ... 2 cite journal author Iggo RD, Jamieson DJ, MacNeill SA, et al. title p68 RNA helicase identification ... Regulation of p68 RNA helicase by calmodulin and protein kinase C. journal J. Biol. Chem. volume ... of p68 RNA helicase acting as a transcriptional coactivator specific for the activation ... Structure and expression of the human p68 RNA helicase gene. journal Nucleic Acids Res. volume 28 ... Nicol SM, Causevic M, Prescott AR, Fuller Pace FV title The nuclear DEAD box RNA helicase p68 interacts ... and associates with p68 RNA helicase. journal J. Biol. Chem. volume 276 issue 20 pages 17448 54 ... helicase is an essential human splicing factor that acts at the U1 snRNA 5 splice site duplex. journal ... helicase and the transcriptional coactivators CBP and p300. journal Oncogene volume 22 issue 1 pages ... M, et al. title Roles of hnRNP A1, SR proteins, and p68 helicase in c H ras alternative splicing ... more details
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