Sir2 whose homology biology homolog in mammal s is known as SIRT1 , SIR2L1 or Sir2 was the first gene ... Sir2 like Proteins journal Biochemical and Biophysical Research Communications volume 273 issue ... ref The term sirtuin is derived from Sir2 and stands for u S u ilent u I u nformation u R u eg u u u lator u T u wo Sir2 prote u in u . ref name pmid15128440 cite journal last1 North first1 Brian J last2 Verdin first2 Eric title Sirtuins Sir2 related NAD dependent protein deacetylases. journal ... 224 ref The name Sir2 is used for the enzyme in the yeast Saccharomyces cerevisiae where it was first ... , Sir 2.1 is used to denote the gene product most similar to yeast Sir2 in structure and activity ... and function to Sir2. ref cite journal last1 Dryden first1 S. C. last2 Nahhas first2 F. A. last3 ... The Sir2 protein family from EMBL s InterPro database ref They add the acetyl group from the protein .... Sir2 is the only Class III histone deacetylase HDAC in budding yeast. ref name pm12067588 cite journal ... 1637 02 00003 X ref The HDAC activity of Sir2 results in tighter packaging of chromatin and a reduction in transcription genetics transcription at the targeted gene locus. The silencing activity of Sir2 ... RNA is transcribed. Limited gene expression overexpression of the Sir2 gene results in a lifespan ... the mother cell can undergo before cell death. Concordantly, deletion of Sir2 results in a 50 reduction in lifespan. ref name pm12067588 In particular, the silencing activity of Sir2, in complex with Sir3 ... McVey first2 M. last3 Guarente first3 L. title The SIR2 3 4 complex and SIR2 alone promote longevity ..., Sir2 activity at the rDNA locus is correlated with a decrease in the formation of rDNA circles. Chromatin silencing, as a result of Sir2 activity, reduces homologous recombination between rDNA repeats ... is the primary way in which yeast are believed to age , then the action of Sir2 in preventing ... the activity of Sir2. Furthermore, removing the Sir2 gene eliminates the life extending effect of caloric ... more details
Leonard P. Guarente is an United States American biologist best known for his research on life span extension in the budding yeast Cerevisiae Saccharomyces cerevisiae . He is currently at the Massachusetts Institute of Technology where he is Novartis Professor of Biology. ref http mit.edu biology www facultyareas facresearch guarente.html Lenord Guarente s faculty website at MIT. ref Guarente, along with graduate students Mitch McVey and Matt Kaeberlein , reported in 1999 that increased activity of the Sir2 protein slows aging in yeast mother cells. ref cite journal author Kaeberlein M, McVey M, Guarente L year 1999 month Oct 1 title The SIR2 3 4 complex and SIR2 alone promote longevity in Saccharomyces cerevisiae by two different mechanisms. journal Genes & Development url http genesdev.cshlp.org content 13 19 2570.full.pdf html volume 13 publisher Cold Spring Harbor Laboratory Press issue 19 pages 2570 80 pmid 10521401 laysummary quote The SIR genes are determinants of life span in yeast mother cells. Here we show that life span regulation by the Sir proteins is independent of their role in nonhomologous end joining. The short life span of a sir3 or sir4 mutant is due to the simultaneous expression of a and alpha mating type information, which indirectly causes an increase in rDNA recombination and likely increases the production of extrachromosomal rDNA circles. The short life span of a sir2 mutant also reveals a direct failure to repress recombination generated by the Fob1p mediated replication block in the rDNA. Sir2p is a limiting component in promoting yeast longevity, and increasing the gene dosage extends the life span in wild type cells. A possible role of the conserved SIR2 in mammalian aging is discussed. doi 10.1101 gad.13.19.2570 pmc 317077 ref Sir2 is the founding member of the Sirtuin family of enzymes. Guarente is recognized as the leading proponent of the hypothesis that caloric restriction slows aging by sirtuin activator activation of Sirtuins . ... more details
Pfam box Symbol SIR2 Name Sir2 family image 1SZD.png width caption Crystallographic structure of yeast sir2 rainbow colored cartoon, N terminus blue, C terminus red complexed with Adenosine diphosphate ADP space filling model , carbon white, oxygen red, nitrogen blue, phosphorus orange and a histone H4 peptide magenta containing an acylated lysine residue displayed as spheres . ref name pmid15150415 ... cleavage and ADP ribose transfer by NAD dependent Sir2 histone protein deacetylases journal ... , PDB2 1s7g , PDB2 1szc , PDB2 1szd , PDB2 1yc2 , PDB2 1yc5 Sirtuin or Sir2 proteins are a class .... ref name pmid15128440 cite journal author North BJ, Verdin E title Sirtuins Sir2 related NAD ... Sirtuins regulate important biological pathways in bacteria , archaea and eukaryote s. The name Sir2 ... Yeast Sir2 and some, but not all, sirtuins are protein deacetylase s. Unlike other known protein deacetylases ..., eukaryotes encode several sirtuins in their genomes. In yeast, roundworms, and fruitflies, sir2 ... L title The Sir2 family of protein deacetylases journal Annu. Rev. Biochem. volume 73 issue 1 ... a lower eukaryote , sirtuin was initially found and named sir2. In more complex mammals, there are seven known enzymes that act as on cellular regulation, as sir2 does in yeast. These genes are designated ... cite journal author Frye R title Phylogenetic classification of prokaryotic and eukaryotic Sir2 like ... a Sir2 or Sir2p, br Hst1 or Hst1p Sirt1 SIRT1 nucleus, cytoplasm deacetylase metabolism br inflammation ... and substrate binding properties of cobB, a Sir2 homolog protein deacetylase from Escherichia ... E title Sirtuins Sir2 related NAD dependent protein deacetylases journal Genome Biol volume 5 ... by nicotinamide altering the NAD cosubstrate specificity of a Sir2 enzyme journal Mol. Cell ... of the human sirtuin SIRT1 shows that it behaves like the yeast sirtuin Sir2 SIRT2 assists ... Ageing Sir2 Resveratrol Biological immortality Caloric restriction Trichostatin A histone deacetylases ... more details
, B.K. 2004 . Sir2 independent life span extension by calorie restriction in yeast. PLoS Biol 2, E296. ref ref Kaeberlein, M., and Powers, R.W., 3rd 2007 . Sir2 and calorie restriction in yeast A skeptical ... more details
Infobox protein Name NAD dependent deacetylase image CobB NAD dependent deacetylase 1S5P.png width caption Crystallographic structure of the CobB protein rainbow colored, N terminus blue, C terminus red complexed with a portion of histone H4 magenta where the sidechain of acylated lysine 16 is displayed as stick diagram. ref name pmid15019790 PDB 1S5P cite journal author Zhao K, Chai X, Marmorstein R title Structure and substrate binding properties of cobB, a Sir2 homolog protein deacetylase from Escherichia coli journal J. Mol. Biol. volume 337 issue 3 pages 731 41 year 2004 month March pmid 15019790 doi 10.1016 j.jmb.2004.01.060 url issn ref Symbol npdA AltSymbols cobB, ycfY IUPHAR id ATC prefix ATC suffix ATC supplemental CAS number CAS supplemental DrugBank EntrezGene 945687 HGNCid OMIM PDB 1S5P RefSeq UniProt P75960 ECnumber Chromosome Arm Band LocusSupplementaryData CobB is a bacterial protein that belongs to the sirtuin family, a broadly conserved family of Nicotinamide adenine dinucleotide NAD dependent protein deacetylase s. ref name pmid12493915 cite journal author Starai VJ, Celic I, Cole RN, Boeke JD, Escalante Semerena JC title Sir2 dependent activation of acetyl CoA synthetase by deacetylation of active lysine journal Science volume 298 issue 5602 pages 2390 2 year 2002 month December pmid 12493915 doi 10.1126 science.1077650 url issn ref ref name pmid18249170 cite journal author Schwer B, Verdin E title Conserved metabolic regulatory functions of sirtuins journal Cell Metab. volume 7 issue 2 pages 104 12 year 2008 month February pmid 18249170 doi 10.1016 j.cmet.2007.11.006 url ref References reflist protein stub Category Proteins ... more details
Onyango P, Celic I, McCaffery JM, Boeke JD, Feinberg AP title SIRT3, a human SIR2 homologue, is an NAD ... A novel VNTR enhancer within the SIRT3 gene, a human homologue of SIR2, is associated with survival ... gene, a human homologue of SIR2, is associated with survival at oldest ages journal Genomics volume ... 1 cite journal author Onyango P, Celic I, McCaffery JM, title SIRT3, a human SIR2 homologue, is an NAD ... of two mouse genes with homology to the yeast Sir2 gene journal Genomics volume 69 issue ... author Frye RA title Phylogenetic classification of prokaryotic and eukaryotic Sir2 like proteins ... to the yeast SIR2 gene Sir2 like proteins sirtuins metabolize NAD and may have protein ADP ribosyltransferase ... more details
in genetics homologs of the Sir2 gene in S. cerevisiae . Members of the sirtuin family are characterized ... Human Sir2 related protein SIRT1 associates with the bHLH repressors HES1 and HEY2 and is involved ... title Characterization of five human cDNAs with homology to the yeast SIR2 gene Sir2 like proteins sirtuins ... journal author Frye RA title Phylogenetic classification of prokaryotic and eukaryotic Sir2 like ... journal author Langley E, Pearson M, Faretta M, et al. title Human SIR2 deacetylates p53 and antagonizes ... regulator of yeast sir2 and human SIRT1. journal J. Biol. Chem. volume 277 issue 47 pages 45099 ... F title Human Sir2 related protein SIRT1 associates with the bHLH repressors HES1 and HEY2 and is involved ... refend External links http www.corante.com pipeline archives 2005 11 20 sir2 surprise.php Corante weblog by Derek Lowe chemist Derek Lowe about sir2 and SIRT1 research. Category Enzymes The PBB ... more details
PBB geneid 23408 Sirtuin silent mating type information regulation 2 homolog 5 S. cerevisiae , also known as SIRT5 is a protein which in humans in encoded by the SIRT5 gene and in other species by the Sirt5 gene. ref name entrez cite web title Entrez Gene SIRT5 sirtuin silent mating type information regulation 2 homolog 5 S. cerevisiae url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 23408 accessdate ref This gene encodes a member of the sirtuin family of proteins, Homology biology Homology of sequences in genetics homologs to the yeast Sir2 protein. Members of the sirtuin family are characterized by a sirtuin core domain and grouped into four classes. The functions of human sirtuins have not yet been determined however, yeast sirtuin proteins are known to regulate epigenetics epigenetic gene silencing and suppress recombination of rDNA. Studies suggest that the human sirtuins may function as intracellular regulatory proteins with mono ADP nucleoside ribosyltransferase ribosyltransferase activity. The protein encoded by this gene is included in class III of the sirtuin family. Alternative splicing of this gene results in two transcript variants. ref name entrez References reflist Further reading refbegin 2 PBB Further reading citations cite journal author Frye RA title Characterization of five human cDNAs with homology to the yeast SIR2 gene Sir2 like proteins sirtuins metabolize NAD and may have protein ADP ribosyltransferase activity. journal Biochem. Biophys. Res. Commun. volume 260 issue 1 pages 273 9 year 1999 pmid 10381378 doi 10.1006 bbrc.1999.0897 cite journal author Frye RA title Phylogenetic classification of prokaryotic and eukaryotic Sir2 like proteins. journal Biochem. Biophys. Res. Commun. volume 273 issue 2 pages 793 8 year 2000 pmid 10873683 doi 10.1006 bbrc.2000.3000 cite journal author Hartley JL, Temple GF, Brasch MA title DNA cloning using in vitro site specific recombination. journal Genome Res. volume 10 issue ... more details
PBB geneid 51547 NAD dependent deacetylase sirtuin 7 is an enzyme that in humans is encoded by the SIRT7 gene . ref name pmid10873683 cite journal author Frye RA title Phylogenetic classification of prokaryotic and eukaryotic Sir2 like proteins journal Biochem Biophys Res Commun volume 273 issue 2 pages 793 8 year 2000 month Aug pmid 10873683 pmc doi 10.1006 bbrc.2000.3000 ref ref name pmid16618798 cite journal author Ford E, Voit R, Liszt G, Magin C, Grummt I, Guarente L title Mammalian Sir2 homolog SIRT7 is an activator of RNA polymerase I transcription journal Genes Dev volume 20 issue 9 pages 1075 80 year 2006 month May pmid 16618798 pmc 1472467 doi 10.1101 gad.1399706 ref ref name entrez cite web title Entrez Gene SIRT7 sirtuin silent mating type information regulation 2 homolog 7 S. cerevisiae url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 51547 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 This gene encodes a member of the sirtuin family of proteins, Homology biology Homology of sequences in genetics homologs to the yeast Sir2 protein. Members of the sirtuin family are characterized by a sirtuin core domain and grouped into four classes. The functions of human sirtuins have not yet been determined however, yeast sirtuin proteins are known to regulate epigenetic gene silencing and suppress recombination of rDNA. Studies suggest that the human sirtuins may function as intracellular regulatory proteins with mono ADP ribosyltransferase activity. The protein encoded by this gene is included in class IV of the sirtuin family. ref name entrez References reflist Further reading refbegin 2 PBB Further reading citations cite journal author de Nigris F, Cerutti J, Morelli C, et al. title Isolation of a SIR like gene, SIR T8, that is overexpressed in thyroid carcinoma cell lines and tissues. journal Br. J. Cancer ... more details
two conserved aging pathways. One of these pathways involves the gene Sir2 , a Nicotinamide adenine dinucleotide NAD dependent histone deacetylase. In yeast, Sir2 is required for genomic silencing at three ... the lack of a connection between circular DNA and aging in higher organisms, extra copies of Sir2 ... replicated by other investigators, and the activator of Sir2 resveratrol does not reproducibly ... 52 year 2007 month October pmid 17875315 doi 10.1016 j.mad.2007.07.007 ref . Whether the Sir2 homologues ... with extended lifespan. In yeast, Sir2 activity is regulated by the nicotinamidase PNC1. PNC1 is transcriptionally ... the activity of Sir2. A nicotinamidase found in humans, known as PBEF , may serve a similar ... in biology between humans and model organisms. Sir2 activity has been shown to increase under ... activate Sir2. Resveratrol , a stilbenoid found in the skin of red grape s, was reported to extend ... by independent investigators ref name resveratrol . It has been shown to activate Sir2 ... dependent on Sir2. Gene expression is imperfectly controlled, and it is possible that random ... akt 1 akt 2 PHB1 daf 16 PHB2 daf 12 CDC7 ctl 1 BUD1 old 1 RTG2 spe 26 RPD3 clk 1 HDA1 mev 1 SIR2 AMPK ... more details
The yeast sirtuin Sir2 3 4p complex is found in abundance at telomeres , where it participates in the formation ... competitive inhibitor of Sir2 and SIRT1 , and proposed the molecule as a physiological regulator ... co published that resveratrol extends the lifespan of worms and flies in a SIR2 dependent manner ... more details
Phylogenetic classification of prokaryotic and eukaryotic Sir2 like proteins journal Biochem. Biophys ... last8 Shenmen first8 CM last9 Schuler first9 GD cite journal author North BJ title The human Sir2 ortholog ... M title Sir2 regulates skeletal muscle differentiation as a potential sensor of the redox state journal ... more details
question. In the 3153A strain, a gene called SIR2 for silent information regulator has been found that seems to be important for phenotypic switching. SIR2 was originally found in Saccharomyces ... in the control of mating type are found in these silent regions, and SIR2 represses their expression ... SIR2 implicated in phenotypic switching suggests it too has silent regions controlled by SIR2 ... event. How SIR2 itself is regulated in S. cerevisiae may yet provide clues as to the switching mechanisms ... and back again the SIR2 silencing gene has a say in Candida s colony type work NCBI Coffeebreak ... more details
Caloric restriction mimetics CRM try to mimic the substantial anti aging effects caloric restriction CR has on many laboratory animals. In other words, the administration of a CRM results in the same physiological changes seen in CR itself. One way CRM work is by influencing specific genes that ultimately affect either cell repair or cell death. Candidate compounds include Resveratrol is found in red wine and grape s Citation needed date December 2007 . Many supplement companies market inexpensive concentrates. Resveratrol is a natural phenol ic plant chemical with proven beneficial cardiovascular effects. What is more, resveratrol is a potent CRM. In yeast, it stimulates Sir2, increasing DNA stability and extending life span by 70 . It is believed that it works the same way in humans, i.e., by activating the human homologue SIRT1, which results in reduced apoptosis in the liver, blood, and skin, as well as reduced risk of age related chronic disease. Research shows that resveratrol possesses an anticancer activity that is mediated through p53 modulation. A derivative of resveratrol can also block cells from dividing, without involving p53, thus safeguarding against unauthorised cell replication that may result in cancer. Metformin mimics the gene expression of CR mice Citation needed date December 2007 , and has extended mice s maximum lifespans Citation needed date December 2007 . It is already clinically approved to treat diabetes , and has been used for this indication for the past 40 years. It is considered to be a receptor sensitizer, because it enhances the sensitivity of insulin receptors on the surface of muscle and fat cells. Metformin is able to activate genes that reduce the production of glucose by the liver, thus reducing the risk of glycosylation and other age related damage. In addition, metformin can reduce the gene expression for enzymes that increase oxidation of fatty acids. In experiments, genes encoding for glucokinase and liver type pyruvate k ... more details
PBB geneid 51548 Mono ADP ribosyltransferase sirtuin 6 is an enzyme that in humans is encoded by the SIRT6 gene . ref name pmid10873683 cite journal author Frye RA title Phylogenetic classification of prokaryotic and eukaryotic Sir2 like proteins journal Biochem Biophys Res Commun volume 273 issue 2 pages 793 8 year 2000 month Aug pmid 10873683 pmc doi 10.1006 bbrc.2000.3000 ref ref name entrez cite web title Entrez Gene SIRT6 sirtuin silent mating type information regulation 2 homolog 6 S. cerevisiae url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 51548 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 This gene encodes a member of the sirtuin family of proteins, Homology biology Homology of sequences in genetics homologs to the yeast Sir2 protein. Members of the sirtuin family are characterized by a sirtuin core domain and grouped into four classes. The functions of human sirtuins have not yet been determined however, yeast sirtuin proteins are known to regulate epigenetic gene silencing and suppress recombination of rDNA. Studies suggest that the human sirtuins may function as intracellular regulatory proteins with mono ADP ribosyltransferase activity. The protein encoded by this gene is included in class IV of the sirtuin family. ref name entrez Recent evidence suggests that the protein might act as the primary regulator for DNA repair activities in reaction to oxidative stress in mammals. ref Citation last Mao first Zhiyong year 2011 title SIRT6 Promotes DNA Repair Under Stress by Activating PARP1 publisher AAAS url http www.sciencemag.org content 332 6036 1443.abstract accessdate June 17, 2011 ref References reflist Further reading refbegin 2 PBB Further reading citations cite journal author Maruyama K, Sugano S title Oligo capping a simple method to replace the cap structure of eukaryotic mRNAs with oligori ... more details
, Sir2 and others. These functions are all known to regulate aging. Genes involved in these mechanisms are TOR, PKA, SCH9, MSN2 4, RIM15, SIR2,... ref cite journal last1 Kaeberlein first1 Matt last2 ... 007 6381 y ref ref cite journal last1 Chen first1 D last2 Guarente first2 L title SIR2 a potential target ... gene N.htm publisher USA Today accessdate 2007 05 03 first Dan last Vergano date 3 May 2007 ref Sir2 ... issue 7 pages 1033 1042 year 1997 pmid 9428525 doi 10.1016 S0092 8674 00 80493 6 ref In mammals Sir2 ... that the gene Sir2 may underlie the effect of calorie restriction in mammals by protecting cells ... 10.1038 nature02583 ref Sir2 SIRT1 and resveratrol Attempts are being made to develop CR mimetic s interventions ... to activate Sir2 SIRT1 and extend the lifespan of yeast, ref cite journal last1 Howitz first1 ... lifespan if the Sir2 gene was mutated. A 2010 study concluded that SRT1720 and resveratrol are not direct ... Seattle believe that Sinclair s work on resveratrol is an artifact and that the Sir2 gene has no relevance ... more details
, C., Suh, Y., Zhou, Z., Liu, X., Kennedy, B.K., and Kaeberlein, M. 2011. Sir2 deletion prevents lifespan ... 42. Kaeberlein, M. and Kennedy, B.K. 2007. Does resveratrol activate yeast Sir2 in vivo? Aging Cell ... mediates SIR2 independent life span extension by calorie restriction . Science 312 1312. 51. Nitta .... The enigmatic role of Sir2 in aging. Cell 123 548 550. 56. Kaeberlein, M., Hu, D., Kerr, E.O., Tsuchiya ..., M., Kirkland, K.T., Fields, S., and Kennedy, B.K. 2004. Sir2 independent life span extension by calorie ... more details
Sirtuin 1 SIRT1 , SIRT2 , SIRT3 , SIRT4 , SIRT5 , SIRT6 , SIRT7 Sir2 in the yeast Saccharomyces ... to Class II and silent information regulator 2 Sir2 corresponding to Class III. ref name pmid15352162 ... more details
Sir2 Der Nersessian, 52 ref The Gospel of 1262 MS No. 2660 was commissioned by Prince Levon, copied ... among the signed works of Roslin. ref name Sir2 The manuscript was kept in Sivas since the 17th ... more details
C title Nicotinamide riboside promotes Sir2 silencing and extends lifespan via Nrk and Urh1 Pnp1 ... Histone deacetylase deacetylases , such as Sir2 . ref Cite journal author North B, Verdin E title Sirtuins Sir2 related NAD dependent protein deacetylases journal Genome Biol volume 5 issue 5 page 224 ... structure. ref Cite journal author Blander G, Guarente L title The Sir2 family of protein deacetylases ... more details
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