Piwi protein

An Argonaute-family branch binding piRNAs. Cytoplasmic cleavage and nuclear transcriptional silencing protect the germline in many animals, with important species and tissue differences.

The Caenorhabditis elegans Piwi-family protein associated with 21U piRNAs and germline surveillance of RNA expression.

Recognition by its associated small RNAs helps distinguish transcripts for germline surveillance. Establishing a persistent silenced state additionally involves downstream pathways, so initial recognition and long-term maintenance are different stages. ^[ref]

A mouse Piwi-family protein associated with fetal male germ-cell transposon repression and de novo DNA methylation.

A mouse Piwi-family protein participating in germ-cell piRNA biogenesis and transposon control.

Its associated guide RNAs contribute sequence information for recognition of transposon-related material. Repression can involve both RNA-level and chromatin-associated outputs, depending on developmental stage and partner factors. ^[ref]

A Drosophila Piwi-family protein that participates with Aubergine in piRNA ping-pong amplification.

Complementary cleavage relationships between small-RNA molecular populations can reinforce production of transposon-targeting guides. The resulting signature links sequence recognition to amplification rather than simply accumulating every small RNA indiscriminately. ^[ref]

A Drosophila Piwi-family protein participating in germline piRNA-mediated regulation, including ping-pong amplification.

It binds selected small RNAs and participates in transcript recognition and cleavage within a germline defence network. Its relationship with AGO3 helps amplify appropriate guide molecular populations, linking molecular specificity to transposon control. ^[ref]