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Structure of Thermus Thermophilus Cse3 bound to an RNA representing a product complexStructure of Thermus Thermophilus Cse3 bound to an RNA representing a product complex
Structural highlights
Function[CAS6_THET8] CRISPR (clustered regularly interspaced short palindromic repeat), is an adaptive immune system that provides protection against mobile genetic elements (viruses, transposable elements and conjugative plasmids). CRISPR clusters contain sequences complementary to antecedent mobile elements and target invading nucleic acids. CRISPR clusters are transcribed and processed into CRISPR RNA (crRNA). This enzyme processes pre-crRNA into individual crRNA units, but may not actually undergo enzyme turnover, retaining the crRNA product (PubMed:21572442). Generates a 2',3'-cyclic phosphodiester.[1] [2] Publication Abstract from PubMedIn bacteria and archaea, small RNAs derived from clustered, regularly interspaced, short palindromic repeat (CRISPR) loci are involved in an adaptable and heritable gene-silencing pathway. Resistance to phage infection is conferred by the incorporation of short invading DNA sequences into the genome as CRISPR spacer elements separated by short repeat sequences. Processing of long primary transcripts (pre-crRNAs) containing these repeats by an RNA endonuclease generates the mature effector RNAs that interfere with phage gene expression. Here we describe structural and functional analyses of the Thermus thermophilus CRISPR Cse3 endonuclease. High-resolution X-ray structures of Cse3 bound to repeat RNAs model both the pre- and post-cleavage complexes associated with processing the pre-crRNA. These structures establish the molecular basis of a specific CRISPR RNA recognition and suggest the mechanism for generation of effector RNAs responsible for gene silencing. Recognition and maturation of effector RNAs in a CRISPR interference pathway.,Gesner EM, Schellenberg MJ, Garside EL, George MM, Macmillan AM Nat Struct Mol Biol. 2011 May 15. PMID:21572444[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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