4ym7

RNA polymerase I structure with an alternative dimer hingeRNA polymerase I structure with an alternative dimer hinge

Structural highlights 4ym7 is a 60 chain structure with sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 5.5Å Ligands: Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function RPA1_YEAST DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic core component of RNA polymerase I which synthesizes ribosomal RNA precursors. Forms the polymerase active center together with the second largest subunit. A single stranded DNA template strand of the promoter is positioned within the central active site cleft of Pol I. A bridging helix emanates from RPA1 and crosses the cleft near the catalytic site and is thought to promote translocation of Pol I by acting as a ratchet that moves the RNA-DNA hybrid through the active site by switching from straight to bent conformations at each step of nucleotide addition (By similarity). Publication Abstract from PubMed RNA polymerase I (Pol I) is the central, 14-subunit enzyme that synthesizes the ribosomal RNA (rRNA) precursor in eukaryotic cells. The recent crystal structure of Pol I at 2.8 A resolution revealed two novel elements: the `expander' in the active-centre cleft and the `connector' that mediates Pol I dimerization [Engel et al. (2013), Nature (London), 502, 650-655]. Here, a Pol I structure in an alternative crystal form that was solved by molecular replacement using the original atomic Pol I structure is reported. The resulting alternative structure lacks the expander but still shows an expanded active-centre cleft. The neighbouring Pol I monomers form a homodimer with a relative orientation distinct from that observed previously, establishing the connector as a hinge between Pol I monomers. An alternative RNA polymerase I structure reveals a dimer hinge.,Kostrewa D, Kuhn CD, Engel C, Cramer P Acta Crystallogr D Biol Crystallogr. 2015 Sep 1;71(Pt 9):1850-5. doi:, 10.1107/S1399004715012651. Epub 2015 Aug 25. PMID:26327374 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4ym7, resolution 5.50Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image