PDBsum entry 6tru

Transcription

PDB id: 6tru

Contents

Protein chains

280 a.a.

263 a.a.

264 a.a.

PDB id:

6tru

Name:

Transcription

Title:

Crystal structure of the n-terminal half of the tfiih subunit p52

Structure:

RNA polymerase ii transcription factor b subunit 2. Chain: b, a, c, d. Engineered: yes

Source:

Chaetomium thermophilum var. Thermophilum dsm 1495. Organism_taxid: 759272. Gene: ctht_0044720. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.80Å R-factor: 0.188 R-free: 0.209

Authors:

W.Koelmel,J.Kuper,E.Schoenwetter,C.Kisker

Key ref:

J.Kappenberger et al. (2020). How to limit the speed of a motor: the intricate regulation of the XPB ATPase and translocase in TFIIH. Nucleic Acids Res, 48, 12282-12296. PubMed id: 33196848 DOI: 10.1093/nar/gkaa911

Date:

19-Dec-19 Release date: 21-Oct-20

Protein chains

G0S965  (G0S965_CHATD) -  RNA polymerase II transcription factor B subunit 2 from Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)

Seq: 514 a.a.

Struc: 280 a.a.

Protein chain

G0S965  (G0S965_CHATD) -  RNA polymerase II transcription factor B subunit 2 from Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)

Seq: 514 a.a.

Struc: 263 a.a.

Protein chain

G0S965  (G0S965_CHATD) -  RNA polymerase II transcription factor B subunit 2 from Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)

Seq: 514 a.a.

Struc: 264 a.a.

Enzyme reactions

• Enzyme class: Chains B, A, C, D: E.C.?

DOI no: 10.1093/nar/gkaa911

Nucleic Acids Res 48:12282-12296 (2020)

PubMed id: 33196848

How to limit the speed of a motor: the intricate regulation of the XPB ATPase and translocase in TFIIH.

J.Kappenberger, W.Koelmel, E.Schoenwetter, T.Scheuer, J.Woerner, J.Kuper, C.Kisker.

ABSTRACT

The superfamily 2 helicase XPB is an integral part of the general transcription factor TFIIH and assumes essential catalytic functions in transcription initiation and nucleotide excision repair. The ATPase activity of XPB is required in both processes. We investigated the interaction network that regulates XPB via the p52 and p8 subunits with functional mutagenesis based on our crystal structure of the p52/p8 complex and current cryo-EM structures. Importantly, we show that XPB's ATPase can be activated either by DNA or by the interaction with the p52/p8 proteins. Intriguingly, we observe that the ATPase activation by p52/p8 is significantly weaker than the activation by DNA and when both p52/p8 and DNA are present, p52/p8 dominates the maximum activation. We therefore define p52/p8 as the master regulator of XPB acting as an activator and speed limiter at the same time. A correlative analysis of the ATPase and translocase activities of XPB shows that XPB only acts as a translocase within the context of complete core TFIIH and that XPA increases the processivity of the translocase complex without altering XPB's ATPase activity. Our data define an intricate network that tightly controls the activity of XPB during transcription and nucleotide excision repair.