6fdf

Crystal structure of S. pombe Dnmt2 methyltransferase

spinqualitylabelsall models 6fdf, resolution 1.70Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 6fdf is a 4 chain structure with sequence from Schizosaccharomyces pombe. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.697Å Ligands: GOL, SAH Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function PMT1M_SCHPO Specifically methylates cytosine 38 in the anticodon loop of tRNA(Asp). Can also methylate cytosine 38 in tRNA(Glu), albeit to a lower level, but not tRNA(Lys). Pmt1-dependent tRNA methylation is induced by nitrogen limitation and depends on the nutrient-sensing protein kinase sck2. Does not have DNA-methylation activity. Publication Abstract from PubMed Dnmt2 methylates cytosine at position 38 of tRNA(Asp) in a variety of eukaryotic organisms. A correlation between the presence of the hypermodified nucleoside queuosine (Q) at position 34 of tRNA(Asp) and the Dnmt2 dependent C38 methylation was recently found in vivo for S. pombe and D. discoideum. We demonstrate a direct effect of the Q-modification on the methyltransferase catalytic efficiency in vitro, as Vmax/K0.5 of purified S. pombe Dnmt2 shows an increase for in vitro transcribed tRNA(Asp) containing Q34 to 6.27 * 10(-3) s(-1) microM(-1) compared to 1.51 * 10(-3) s(-1) microM(-1) for the unmodified substrate. Q34tRNA(Asp) exhibits an only slightly increased affinity for Dnmt2 in comparison to unmodified G34tRNA. In order to get insight into the structural basis for the Q-dependency, the crystal structure of S. pombe Dnmt2 was determined at 1.7 A resolution. It closely resembles the known structures of human and E. histolytica Dnmt2, and contains the entire active site loop. The interaction with tRNA was analyzed by means of mass-spectrometry using UV cross-linked Dnmt2-tRNA complex. These cross-link data and computational docking of Dnmt2 and tRNA(Asp) reveal Q34 positioned adjacent to the S-adenosylmethionine occupying the active site, suggesting that the observed increase of Dnmt2 catalytic efficiency by queuine originates from optimal positioning of the substrate molecules and residues relevant for methyl transfer. Structural insights into the stimulation of S. pombe Dnmt2 catalytic efficiency by the tRNA nucleoside queuosine.,Johannsson S, Neumann P, Wulf A, Welp LM, Gerber HD, Krull M, Diederichsen U, Urlaub H, Ficner R Sci Rep. 2018 Jun 11;8(1):8880. doi: 10.1038/s41598-018-27118-5. PMID:29892076 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also TRNA methyltransferase 3D structures

Proteopedia Page Contributors and Editors (what is this?)

OCA