pfam17146: PIN_6 (This model is not part of the current CDD release)
PIN domain of ribonuclease
This is a PIN domain found in eukaryotic ribonuclease Nob1 and archaeal ribonuclease VapC1. Budding yeast Nob1 is involved in proteasomal and 40S ribosomal subunit biogenesis. VapC1 is a toxic component and a ribonuclease of a toxin-antitoxin (TA) module. PIN domains are small protein domains identified by the presence of three strictly conserved acidic residues. Apart from these three residues, there is poor sequence conservation. PIN domains are found in eukaryotes, eubacteria and archaea. In eukaryotes they are ribonucleases involved in nonsense mediated mRNA decay and in processing of 18S ribosomal RNA. In prokaryotes, they are the toxic components of toxin-antitoxin (TA) systems, their toxicity arising by virtue of their ribonuclease activity. The PIN domain TA systems are now called VapBC TAs(virulence associated proteins), where VapB is the inhibitor and VapC, the PIN-domain ribonuclease toxin.
Jiyao W et al.(2023). "The conserved domain database in 2023.",