1sj3 | pdb_00001sj3

Hepatitis Delta Virus Gemonic Ribozyme Precursor, with Mg2+ Bound

spinqualitylabelsall models 1sj3, resolution 2.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1sj3 is a 2 chain structure with sequence from Hepatitis delta virus and Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: MG Related: 1cx0, 1drz, 1sj4 Gene: SNRPA (Homo sapiens) Resources: FirstGlance, OCA, RCSB, PDBsum Function [SNRPA_HUMAN] Binds stem loop II of U1 snRNA. It is the first snRNP to interact with pre-mRNA. This interaction is required for the subsequent binding of U2 snRNP and the U4/U6/U5 tri-snRNP. In a snRNP-free form (SF-A) may be involved in coupled pre-mRNA splicing and polyadenylation process. Binds preferentially to the 5'-UGCAC-3' motif in vitro. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Ribozymes enhance chemical reaction rates using many of the same catalytic strategies as protein enzymes. In the hepatitis delta virus (HDV) ribozyme, site-specific self-cleavage of the viral RNA phosphodiester backbone requires both divalent cations and a cytidine nucleotide. General acid-base catalysis, substrate destabilization and global and local conformational changes have all been proposed to contribute to the ribozyme catalytic mechanism. Here we report ten crystal structures of the HDV ribozyme in its pre-cleaved state, showing that cytidine is positioned to activate the 2'-OH nucleophile in the precursor structure. This observation supports its proposed role as a general base in the reaction mechanism. Comparison of crystal structures of the ribozyme in the pre- and post-cleavage states reveals a significant conformational change in the RNA after cleavage and that a catalytically critical divalent metal ion from the active site is ejected. The HDV ribozyme has remarkable chemical similarity to protein ribonucleases and to zymogens for which conformational dynamics are integral to biological activity. This finding implies that RNA structural rearrangements control the reactivity of ribozymes and ribonucleoprotein enzymes. A conformational switch controls hepatitis delta virus ribozyme catalysis.,Ke A, Zhou K, Ding F, Cate JH, Doudna JA Nature. 2004 May 13;429(6988):201-5. PMID:15141216 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Nucleoprotein Ribozyme

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