6dve
From Proteopedia
Crystal structure of Mycobacterium tuberculosis transcription initiation complex(ECF selenomethionine-labelled sigma factor L) with 6 nt spacer
Structural highlights
Function[RPOZ_MYCTU] Promotes RNA polymerase assembly. Latches the N- and C-terminal regions of the beta' subunit thereby facilitating its interaction with the beta and alpha subunits.[1] [RPOA_MYCTU] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_00059][2] [RPOC_MYCTU] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_01322][3] [RPOB_MYCTU] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_01321] [SIGL_MYCTU] Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released. Extracytoplasmic function (ECF) sigma factors are held in an inactive form by an anti-sigma factor until released by regulated intramembrane proteolysis. Over-expression of SigL induces 19-28 genes including polyketide synthases, secreted and membrane proteins. Might play a minor role in regulating SigB.[4] [5] Publication Abstract from PubMedExtracytoplasmic (ECF) sigma factors, the largest class of alternative sigma factors, are related to primary sigma factors, but have simpler structures, comprising only two of six conserved functional modules in primary sigma factors: region 2 (sigmaR2) and region 4 (sigmaR4). Here, we report crystal structures of transcription initiation complexes containing Mycobacterium tuberculosis RNA polymerase (RNAP), M. tuberculosis ECF sigma factor sigma(L), and promoter DNA. The structures show that sigmaR2 and sigmaR4 of the ECF sigma factor occupy the same sites on RNAP as in primary sigma factors, show that the connector between sigmaR2 and sigmaR4 of the ECF sigma factor-although shorter and unrelated in sequence-follows the same path through RNAP as in primary sigma factors, and show that the ECF sigma factor uses the same strategy to bind and unwind promoter DNA as primary sigma factors. The results define protein-protein and protein-DNA interactions involved in ECF-sigma-factor-dependent transcription initiation. Structural basis of ECF-sigma-factor-dependent transcription initiation.,Lin W, Mandal S, Degen D, Cho MS, Feng Y, Das K, Ebright RH Nat Commun. 2019 Feb 12;10(1):710. doi: 10.1038/s41467-019-08443-3. PMID:30755604[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|