Protein argonaute

UniProtKB accession:  A4WYU7

Grouped By:  Matching UniProtKB accession

UniProtKB description:  A catalytically inactive argonaute protein. Binds 5'-phosphorylated RNA as the guide (gRNA) and short DNA as target DNA (tDNA); does not bind other nucleic acid combinations, does not bind tDNA alone (PubMed:27325485, PubMed:29996105, PubMed:33333714). Has highest affinity for gRNA that begins with 5'-phospho-U and poor affinity for gRNA with 5'-OH (PubMed:27325485, PubMed:29996105). Upon expression in E.coli, plasmid sequences are found in RsAgo, its induction leads to plasmid degradation and suppression of genes encoded on foreign plasmids, suggesting it may also interfere with transcription (PubMed:24034694, PubMed:27325485). Does not interact with preformed gRNA:tDNA duplexes. Mismatches and nt bulges are tolerated in the ternary complex, however, they significantly reduce the affinity of RsAgo:gRNA for tDNA. Mismatched tDNA can cause dissociation of gRNA from RsAgo (PubMed:29996105). In situ binds 2 populations of RNA (15-19 and 45 nucleotides, nt) and a population of ssDNA 22-24 nt in length. The small sense RNA is probably derived from mRNA degradation and strongly enriched for U in the first and U/C in the second positions. The small DNA is enriched for sequences complementary to the RNA, with 3 nt overhangs on both ends; another nuclease may trim the ends. The sequences are largely derived from exogenous plasmids or genome-encoded foreign elements such as prophages and transposons (PubMed:24034694). Forms a ternary complex with gRNA and double-stranded tDNA only when the tDNA is open (PubMed:33333714).