piRNAs--the ancient hunters of genome invaders.
In addition to miRNAs and siRNAs, a third small RNA silencing system has been uncovered that prevents the spreading of selfish genetic elements. Production of the Piwi-associated RNAs (piRNAs), which mediate the silencing activity in this pathway, is initiated at a few master control regions within the genome. The nature of the primary piRNA-generating transcript is still unknown, but RNA interference (RNAi)-like cleavage events are likely defining the 5'-ends of mature piRNAs. We summarize the recent literature on piRNA biogenesis and function with an emphasis on work in Drosophila, where genetics and biochemistry have met very successfully.
Hartig
Julia Verena
JV
Gene Center of the Ludwig-Maximilians-University, D-81377 München, Germany.
Tomari
Yukihide
Y
Förstemann
Klaus
K
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism; D004249:DNA Damage; D004330:Drosophila / Q000235:genetics / Q000378:metabolism; D020868:Gene Silencing; D016678:Genome; D008957:Models, Genetic; D009154:Mutation; D012313:RNA / Q000235:genetics* / Q000378:metabolism; D020365:RNA Helicases / Q000235:genetics / Q000378:metabolism
D012313:RNA; D020365:RNA Helicases