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<table><tr><td colspan='2'>[[6t9j]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Baker's_yeast Baker's yeast]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6T9J OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6T9J FirstGlance]. <br>
<table><tr><td colspan='2'>[[6t9j]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Baker's_yeast Baker's yeast]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6T9J OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6T9J FirstGlance]. <br>
6t9j is a 3 chain structure with sequence from Baker's yeast. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[SPT20_YEAST] Transcription regulator. May recruit TATA binding protein (TBP) and possibly other basal factors to bind to the TATA box. Functions as component of the transcription regulatory histone acetylation (HAT) complexes SAGA, SALSA and SLIK. SAGA is involved in RNA polymerase II-dependent transcriptional regulation of approximately 10% of yeast genes. At the promoters, SAGA is required for recruitment of the basal transcription machinery. It influences RNA polymerase II transcriptional activity through different activities such as TBP interaction (SPT3, SPT8 and SPT20) and promoter selectivity, interaction with transcription activators (GCN5, ADA2, ADA3 and TRA1), and chromatin modification through histone acetylation (GCN5) and deubiquitination (UBP8). SAGA acetylates nucleosomal histone H3 to some extent (to form H3K9ac, H3K14ac, H3K18ac and H3K23ac). SAGA interacts with DNA via upstream activating sequences (UASs). SALSA, an altered form of SAGA, may be involved in positive transcriptional regulation. SLIK is proposed to have partly overlapping functions with SAGA. It preferentially acetylates methylated histone H3, at least after activation at the GAL1-10 locus.[1] [TRA1_YEAST] Essential component of histone acetyltransferase (HAT) complexes, which serves as a target for activators during recruitment of HAT complexes. Essential for vegetative growth. Functions as a component of the transcription regulatory histone acetylation (HAT) complexes SAGA, SALSA and SLIK. SAGA is involved in RNA polymerase II-dependent transcriptional regulation of approximately 10% of yeast genes. At the promoters, SAGA is required for recruitment of the basal transcription machinery. It influences RNA polymerase II transcriptional activity through different activities such as TBP interaction (SPT3, SPT8 and SPT20) and promoter selectivity, interaction with transcription activators (GCN5, ADA2, ADA3 and TRA1), and chromatin modification through histone acetylation (GCN5) and deubiquitination (UBP8). SAGA acetylates nucleosomal histone H3 to some extent (to form H3K9ac, H3K14ac, H3K18ac and H3K23ac). SAGA interacts with DNA via upstream activating sequences (UASs). SALSA, an altered form of SAGA, may be involved in positive transcriptional regulation. SLIK is proposed to have partly overlapping functions with SAGA. It preferentially acetylates methylated histone H3, at least after activation at the GAL1-10 locus.[2][3] [TAF12_YEAST] Functions as a component of the DNA-binding general transcription factor complex TFIID and the transcription regulatory histone acetylation (HAT) complexes SAGA, SALSA and SLIK. Binding of TFIID to a promoter (with or without TATA element) is the initial step in preinitiation complex (PIC) formation. TFIID plays a key role in the regulation of gene expression by RNA polymerase II through different activities such as transcription activator interaction, core promoter recognition and selectivity, TFIIA and TFIIB interaction, chromatin modification (histone acetylation by TAF1), facilitation of DNA opening and initiation of transcription. SAGA is involved in RNA polymerase II-dependent transcriptional regulation of approximately 10% of yeast genes. At the promoters, SAGA is required for recruitment of the basal transcription machinery. It influences RNA polymerase II transcriptional activity through different activities such as TBP interaction (SPT3, SPT8 and SPT20) and promoter selectivity, interaction with transcription activators (GCN5, ADA2, ADA3 and TRA1), and chromatin modification through histone acetylation (GCN5) and deubiquitination (UBP8). SAGA acetylates nucleosomal histone H3 to some extent (to form H3K9ac, H3K14ac, H3K18ac and H3K23ac). SAGA interacts with DNA via upstream activating sequences (UASs). SALSA, an altered form of SAGA, may be involved in positive transcriptional regulation. SLIK is proposed to have partly overlapping functions with SAGA. It preferentially acetylates methylated histone H3, at least after activation at the GAL1-10 locus.[4][5][6][7][8][9][10][11][12][13]
Publication Abstract from PubMed
Gene transcription by RNA polymerase II is regulated by activator proteins that recruit the coactivator complexes SAGA (Spt-Ada-Gcn5-acetyltransferase)(1,2) and transcription factor IID (TFIID)(2-4). SAGA is required for all regulated transcription(5) and is conserved among eukaryotes(6). SAGA contains four modules(7-9): the activator-binding Tra1 module, the core module, the histone acetyltransferase (HAT) module and the histone deubiquitination (DUB) module. Previous studies provided partial structures(10-14), but the structure of the central core module is unknown. Here we present the cryo-electron microscopy structure of SAGA from the yeast Saccharomyces cerevisiae and resolve the core module at 3.3 A resolution. The core module consists of subunits Taf5, Sgf73 and Spt20, and a histone octamer-like fold. The octamer-like fold comprises the heterodimers Taf6-Taf9, Taf10-Spt7 and Taf12-Ada1, and two histone-fold domains in Spt3. Spt3 and the adjacent subunit Spt8 interact with the TATA box-binding protein (TBP)(2,7,15-17). The octamer-like fold and its TBP-interacting region are similar in TFIID, whereas Taf5 and the Taf6 HEAT domain adopt distinct conformations. Taf12 and Spt20 form flexible connections to the Tra1 module, whereas Sgf73 tethers the DUB module. Binding of a nucleosome to SAGA displaces the HAT and DUB modules from the core-module surface, allowing the DUB module to bind one face of an ubiquitinated nucleosome.
Structure of the transcription coactivator SAGA.,Wang H, Dienemann C, Stutzer A, Urlaub H, Cheung ACM, Cramer P Nature. 2020 Jan;577(7792):717-720. doi: 10.1038/s41586-020-1933-5. Epub 2020 Jan, 22. PMID:31969703[14]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Grant PA, Eberharter A, John S, Cook RG, Turner BM, Workman JL. Expanded lysine acetylation specificity of Gcn5 in native complexes. J Biol Chem. 1999 Feb 26;274(9):5895-900. PMID:10026213
↑ Grant PA, Eberharter A, John S, Cook RG, Turner BM, Workman JL. Expanded lysine acetylation specificity of Gcn5 in native complexes. J Biol Chem. 1999 Feb 26;274(9):5895-900. PMID:10026213
↑ Brown CE, Howe L, Sousa K, Alley SC, Carrozza MJ, Tan S, Workman JL. Recruitment of HAT complexes by direct activator interactions with the ATM-related Tra1 subunit. Science. 2001 Jun 22;292(5525):2333-7. PMID:11423663 doi:http://dx.doi.org/10.1126/science.1060214
↑ Grant PA, Eberharter A, John S, Cook RG, Turner BM, Workman JL. Expanded lysine acetylation specificity of Gcn5 in native complexes. J Biol Chem. 1999 Feb 26;274(9):5895-900. PMID:10026213
↑ Sanders SL, Weil PA. Identification of two novel TAF subunits of the yeast Saccharomyces cerevisiae TFIID complex. J Biol Chem. 2000 May 5;275(18):13895-900. PMID:10788514
↑ Gangloff YG, Sanders SL, Romier C, Kirschner D, Weil PA, Tora L, Davidson I. Histone folds mediate selective heterodimerization of yeast TAF(II)25 with TFIID components yTAF(II)47 and yTAF(II)65 and with SAGA component ySPT7. Mol Cell Biol. 2001 Mar;21(5):1841-53. PMID:11238921 doi:http://dx.doi.org/10.1128/MCB.21.5.1841-1853.2001
↑ Gangloff YG, Romier C, Thuault S, Werten S, Davidson I. The histone fold is a key structural motif of transcription factor TFIID. Trends Biochem Sci. 2001 Apr;26(4):250-7. PMID:11295558
↑ Selleck W, Howley R, Fang Q, Podolny V, Fried MG, Buratowski S, Tan S. A histone fold TAF octamer within the yeast TFIID transcriptional coactivator. Nat Struct Biol. 2001 Aug;8(8):695-700. PMID:11473260 doi:http://dx.doi.org/10.1038/90408
↑ Sanders SL, Jennings J, Canutescu A, Link AJ, Weil PA. Proteomics of the eukaryotic transcription machinery: identification of proteins associated with components of yeast TFIID by multidimensional mass spectrometry. Mol Cell Biol. 2002 Jul;22(13):4723-38. PMID:12052880
↑ Sanders SL, Garbett KA, Weil PA. Molecular characterization of Saccharomyces cerevisiae TFIID. Mol Cell Biol. 2002 Aug;22(16):6000-13. PMID:12138208
↑ Martinez E. Multi-protein complexes in eukaryotic gene transcription. Plant Mol Biol. 2002 Dec;50(6):925-47. PMID:12516863
↑ Grant PA, Schieltz D, Pray-Grant MG, Steger DJ, Reese JC, Yates JR 3rd, Workman JL. A subset of TAF(II)s are integral components of the SAGA complex required for nucleosome acetylation and transcriptional stimulation. Cell. 1998 Jul 10;94(1):45-53. PMID:9674426
↑ Birck C, Poch O, Romier C, Ruff M, Mengus G, Lavigne AC, Davidson I, Moras D. Human TAF(II)28 and TAF(II)18 interact through a histone fold encoded by atypical evolutionary conserved motifs also found in the SPT3 family. Cell. 1998 Jul 24;94(2):239-49. PMID:9695952
↑ Wang H, Dienemann C, Stutzer A, Urlaub H, Cheung ACM, Cramer P. Structure of the transcription coactivator SAGA. Nature. 2020 Jan;577(7792):717-720. doi: 10.1038/s41586-020-1933-5. Epub 2020 Jan, 22. PMID:31969703 doi:http://dx.doi.org/10.1038/s41586-020-1933-5
