*M/c type of non coding RNA
*Found both in nucleus & cytoplasm
*26-31 nucleotide,size varies from 1-100 kb.
*Role in RNA silencing via formation of RNA induced silencing complex(RISC).pi-RNA interacts with ‘piwi’ proteins.
*These pi-RNA complexes have been linked to both epigenetics & post transcriptional gene silencing of ‘retrotransposons’ & other genetic elements in Germ cell lines,particularly those in spermatogenesis.
*Mutations in pi-RNA pathway are found to have reduce fertility in D.Melanogaster.
*Major advances in the pi-RNA field have been achieved by use of “Next generation sequencing techniques”