?cl38923: PIN_Mut7-C-like Superfamily (this model, PSSM-Id:422955 is obsolete and has been replaced by 453890)
PIN domain at the C-terminus of Caenorhabditis elegans exonuclease Mut-7 and related domains The Mut7-C-like family of the PIN domain superfamily includes the C-terminal domain of Caenorhabditis elegans Mut-7 (also known as exonuclease 3'-5' domain-containing protein 3 homolog). Mut-7 is involved in RNA interference (RNAi) and transposon silencing in C. elegans. The Mut7-C PIN domain family is recognized as a genuine PIN domain, however it is not included it in the CDD PIN domain superfamily hierarchical model as it is lacks a core strand and helix (H3 and S3). The PIN (PilT N terminus) domain belongs to a large nuclease superfamily, and were originally named for their sequence similarity to the N-terminal domain of an annotated pili biogenesis protein, PilT, a domain fusion between a PIN-domain and a PilT ATPase domain. The structural properties of the PIN domain indicate its active center, consisting of three highly conserved catalytic residues which coordinate metal ions; in some members additional metal coordinating residues can be found while some others lack several of these key catalytic residues. The PIN active site is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Other PIN domain families are: the FEN-like PIN domain family which includes the PIN domains of Flap endonuclease-1 (FEN1), Exonuclease-1 (EXO1), Mkt1, Gap Endonuclease 1 (GEN1), and Xeroderma pigmentosum complementation group G (XPG) nuclease, 5'-3' exonucleases of DNA polymerase I and bacteriophage T4- and T5-5' nucleases; the VapC-like PIN domain family which includes toxins of prokaryotic toxin/antitoxin operons FitAB and VapBC, as well as, eukaryotic ribonucleases such as Smg6, ribosome assembly factor NOB1, exosome subunit Rrp44 endoribonuclease and, rRNA-processing protein Fcf1; the LabA-like PIN domain family which includes the PIN domains of Synechococcus elongatus LabA (low-amplitude and bright); the PRORP-Zc3h12a-like PIN domain family which includes the PIN domains of of RNase P (PRORP), ribonuclease Zc3h12a; and Bacillus subtilis YacP/Rae1-like PIN domains. Matelska et al. recently classified PIN-like domains into distinct groups, this family includes some sequences belonging to two of these, PIN _10 and PIN_16. |
Jiyao W et al.(2023). "The conserved domain database in 2023.",