Browse
Submit Data
Databases
API
Help

Dataset Information

290 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Crosslinking mass spectrometry of yeast Pol I pre-initiation complex

ABSTRACT: In eukaryotic cells, ribosomal RNA is transcribed by RNA polymerase I (Pol I). To initiate transcription, Pol I requires the assembly of a multi-subunit pre-initiation complex (PIC). In yeast, the minimal PIC includes Pol I, the transcription factor Rrn3 and Core Factor (CF) composed of subunits Rrn6, Rrn7 and Rrn11. We have determined the cryo-EM structure of a 18-subunit yeast Pol I complex together with CF, Rrn3 and transcription scaffold. To aid in modeling the structure based on the cryo-EM map, we performed crosslinking mass spectrometry.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: Katarzyna Buczak

LAB HEAD: Christoph Müller

PROVIDER: PXD006510 | Pride | 2017-07-31

REPOSITORIES: Pride

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
	2mM_DSS_interlinks.xlsx	Xlsx
	2mM_DSS_intralinks.xlsx	Xlsx
	2mM_DSS_looplinks.xlsx	Xlsx
	2mM_DSS_monolinks.xlsx	Xlsx
	5mM_DSS_interlinks.xlsx	Xlsx

Items per page:

1 - 5 of 51

Publications

Structural insights into transcription initiation by yeast RNA polymerase I.

Sadian Yashar Y Tafur Lucas L Kosinski Jan J Jakobi Arjen J AJ Wetzel Rene R Buczak Katarzyna K Hagen Wim Jh WJ Beck Martin M Sachse Carsten C Müller Christoph W CW

The EMBO journal 20170724 18

In eukaryotic cells, RNA polymerase I (Pol I) synthesizes precursor ribosomal RNA (pre-rRNA) that is subsequently processed into mature rRNA. To initiate transcription, Pol I requires the assembly of a multi-subunit pre-initiation complex (PIC) at the ribosomal RNA promoter. In yeast, the minimal PIC includes Pol I, the transcription factor Rrn3, and Core Factor (CF) composed of subunits Rrn6, Rrn7, and Rrn11. Here, we present the cryo-EM structure of the 18-subunit yeast Pol I PIC bound to a tr ...[more]

PMID: 28739580

Similar Datasets

Structure of transcription preinitiation complex engaged with the +1 nucleosome

Project description:The preinitiation complex (PIC) assembles on promoters of protein-coding genes to position RNA polymerase II (Pol II) for transcription initiation. Previous structural studies revealed the PIC on different promoters, but did not address how the PIC assembles in chromatin. In the yeast Saccharomyces cerevisiae, PIC assembly occurs adjacent to the +1 nucleosome that is positioned downstream of the core promoter. Here we present the cryo-EM structure of the yeast PIC bound to promoter DNA and the +1 nucleosome at a resolution of 3.4–3.9 Å. The general transcription factor TFIIH forms four contacts with the nucleosome, indicating how PIC assembly can be assisted by the +1 nucleosome. The TFIIH subunit Ssl2 (XPB in human TFIIH) forms a wedge between promoter DNA and the nucleosome, stabilizing two turns of DNA that are detached from the nucleosome. During subsequent scanning for the transcription start site (TSS), three additional turns of DNA can be detached before the partially unraveled nucleosome may counteract further scanning, explaining why TSSs are located at a distance of ~60 bp from the dyad of the +1 nucleosome in yeast.

2023-03-11 | PXD029840 | Pride

Structural basis of SNAPc-dependent snRNA transcription intiation by RNA polymerase II

Project description:RNA Polymerase II (Pol II) carries out transcription of both protein-coding and non-coding genes. Whereas Pol II initiation at protein-coding genes has been studied in detail, Pol II initiation at non-coding genes such as small nuclear RNA (snRNA) genes is not understood at the structural level. Here we study Pol II initiation at snRNA gene promoters and show that the snRNA-activating protein complex (SNAPc) enables DNA opening and transcription initiation independent of TFIIE and TFIIH in vitro. We then resolve cryo-EM structures of the SNAPc-containing Pol II preinitiation complex (PIC) assembled on U1 and U5 snRNA promoters. The core of SNAPc binds two turns of DNA and recognizes the snRNA promoter-specific proximal sequence element (PSE) located upstream of the TATA box-binding protein TBP. Two extensions of SNAPc called wing-1 and wing-2 bind TFIIA and TFIIB, respectively, explaining how SNAPc directs Pol II to snRNA promoters. Comparison of structures of closed and open promoter complexes elucidates TFIIH-independent DNA opening. These results provide the structural basis of Pol II initiation at non-coding RNA gene promoters.

2023-03-11 | PXD033638 | Pride

Structure of transcribing RNA polymerase II-Elongin complex

Project description:Elongin is a hetero-trimeric elongation factor for RNA polymerase (Pol) II transcription that is conserved among metazoa. We solved three structures of human Elongin bound to transcribing Pol II using cryo-EM assisted by crosslinking mass spectrometry. The structures show that Elongin subunit ELOA binds the RPB2 side of Pol II and anchors the ELOB-8 ELOC subunit heterodimer. ELOA contains an N-terminal ‘latch’ that binds between the end of the RPB1 bridge helix and the funnel helices, thereby inducing a conformational change near the Pol II active center. The latch is strictly required for the elongation-stimulatory activity of Elongin, but not for its binding to Pol II, indicating that Elongin functions by allosterically influencing the conformational mobility of the active center. Structural comparisons show that Elongin binding to Pol II is incompatible with association of super elongation complex, the PAF1 complex, and RTF1, which also contains a latch element that stimulates Pol II.

2023-10-11 | PXD045446 | Pride

Structure of Saccharomyces cerevisiae Mediator-RNA polymerase II pre-initiation complex for divergent transcription

Project description:This study has determined structure of transcription initiation complexes including a DNA-bound activator, RNA polymerase II (Pol II), and Mediator on a divergent promoter GAL80/SUT719 using a combination of cryo-EM and XL-MS analyses. Our cryo-EM single-particle analysis reveals a dimeric form of Med-PIC through the Mediator Tail module induced by the activator protein. Density of the upstream DNA bound to the Gal4-VP16 was identifiable along the Mediator Tail module, while XL-MS localized flexible regions that were not visible by cryo-EM analysis, such as activator-binding domains (ABDs and KIX).

2024-05-22 | PXD036149 | Pride

Allosteric transcription stimulation by super elongation complex

Project description:The super elongation complex (SEC) contains the positive transcription elongation factor b (P-TEFb) and a subcomplex, ELL2-EAF1, which stimulates transcription elongation by RNA polymerase II (Pol II). Here we report the cryo-EM structure of ELL2-EAF1 bound to a Pol II elongation complex at 2.8 Å resolution. The ELL2-EAF1 dimerization module directly binds the Pol II lobe, explaining how SEC delivers P-TEFb to Pol II. The same site on the lobe also binds the initiation factor TFIIF, consistent with SEC binding only after the transition from transcription initiation to elongation. Structure-guided functional analysis shows that elongation stimulation requires the dimerization module and an ELL2 protein linker that tethers this module to the Pol II protrusion. Our results show that SEC stimulates elongation allosterically and indicate that this stimulation involves stabilization of a further closed conformation of the Pol II active center cleft.

2021-07-15 | PXD024457 | Pride

The cross-linking mass spectrometry (CX-MS) results of Human TIP60 complex (hTIP60)

Project description:Mammalian TIP60 is a multi-functional enzyme with histone acetylation and histone dimer exchange activities. It plays roles in diverse cellular processes including transcription, DNA repair, cell cycle control, and embryonic development. We performed structural study on human TIP60 complex with cryo-electron microscopy. The structural model of human TIP60 complex was built based on the high-resolution cryo-EM maps, assisted by cross-linking mass spectrometry (CX-MS) and AlphaFold2 prediction.

2024-07-11 | PXD048625 | Pride

Systematic mutagenesis of TFIIH subunit p52/Tfb2 identifies residues required for XPB/Ssl2 subunit function and genetic interactions with TFB6

Project description:TFIIH is an evolutionarily conserved complex that plays central roles in both RNA polymerase II (pol II) transcription and DNA repair. As an integral component of the pol II Pre-Initiation Complex (PIC), TFIIH regulates pol II enzyme activity in numerous ways. The TFIIH subunit XPB/Ssl2 is an ATP-dependent DNA translocase that stimulates promoter opening prior to transcription initiation. Crosslinking-mass spectrometry and cryo-EM results have shown a conserved interaction network involving XPB/Ssl2 and the C-terminal Hub region of the TFIIH p52/Tfb2 subunit, but the functional significance of specific residues is unclear. Here, we systematically mutagenized the HubA region of Tfb2 and screened for growth phenotypes in a TFB6 deletion background in Saccharomyces cerevisiae. We identified six lethal and twelve conditional mutants. Slow growth phenotypes of all but three conditional mutants were relieved in the presence of TFB6, thus identifying a functional interaction between Tfb2 HubA mutants and Tfb6, a protein that dissociates Ssl2 from TFIIH. Our biochemical analysis of Tfb2 mutants with severe growth phenotypes revealed defects in Ssl2 association, with similar results in human cells. Further characterization of these tfb2 mutant cells revealed defects in GAL gene induction, and reduced occupancy of TFIIH and pol II at GAL gene promoters, suggesting that functionally competent TFIIH is required for proper pol II recruitment to PICs in vivo. Consistent with recent structural models of TFIIH, our results identify key residues in the p52/Tfb2 HubA domain that are required for stable incorporation of XPB/Ssl2 into TFIIH, and for pol II transcription.

2022-09-07 | PXD036107 | Pride

Systematic mutagenesis identifies p52/Tfb2 residues required for XPB/Ssl2 function within TFIIH and genetic interactions with TFB6

Project description:TFIIH is an evolutionarily conserved complex that plays central roles in both RNA polymerase II (pol II) transcription and DNA repair. As an integral component of the pol II Pre-Initiation Complex (PIC), TFIIH regulates the activity of the pol II enzyme in numerous ways. The TFIIH subunit XPB/Ssl2 is an ATP-dependent DNA translocase that stimulates promoter opening prior to transcription initiation. Crosslinking-mass spectrometry and cryo-EM results have shown a conserved interaction network involving XPB/Ssl2 and the C-terminal Hub region of the TFIIH p52/Tfb2 subunit. Here, we systematically mutagenized the HubA region of Tfb2 and screened for growth phenotypes in a TFB6 deletion background in Saccharomyces cerevisiae. We identified six lethal and twelve conditional mutants. Slow growth phenotypes of all but three conditional mutants were relieved in the presence of TFB6, thus identifying a functional interaction between Tfb2 HubA mutants and Tfb6, a protein that dissociates Ssl2 from TFIIH. Biochemical analysis of Tfb2 mutants with severe growth phenotypes revealed defects in Ssl2 association, with similar results in human cells. Further characterization of these tfb2 mutant cells revealed defects in GAL gene induction, and reduced occupancy of TFIIH and pol II at GAL gene promoters, suggesting that functionally competent TFIIH is required for proper pol II recruitment to PICs in vivo. Consistent with recent structural models of TFIIH, our results identify key residues in the p52/Tfb2 HubA domain that are required for stable incorporation of XPB/Ssl2 into TFIIH, and for pol II transcription.

2023-03-11 | PXD035576 | Pride

Cross-linking mass spectrometry of the CCAN and CCAN-Cenp-A complexes

Project description:Here we performed a cross-linking mass spectrometry analysis of the inner kinethocore complex CCAN and of the complex associated with a CenpA-nucleosome (CCAN-CenpA)from budding yeast. These experiments validated the cryo-EM structure of both complexes and provided additional structural insights on the complex organization.

2019-08-20 | PXD013769 | Pride

Pol II and its associated epigenetic marks are present at pol III-transcribed non-coding RNA genes (I)

Project description:Epigenetic control is an important aspect of gene regulation. Despite detailed understanding of many examples, the transcription of non-coding RNA genes by RNA polymerase (pol) III is less well characterized. Here we profile the epigenetic features of pol III target genes throughout the human genome. This reveals that the chromatin landscape of pol III-transcribed genes resembles that of pol II templates in many ways, although there are also clear differences. Our analysis also discovered an entirely unexpected phenomenon, namely that pol II co-localizes with the majority of genomic loci that are bound by pol III. Chip-Seq experiments for six samples: Pol III, TFIIIB, TFIIIC, H3K4me3 in HeLa cells and Pol III, S2 phos Pol II in CD4+ cells.

2010-04-25 | E-GEOD-20040 | biostudies-arrayexpress