Piwi-interacting RNAs (piRNAs) are a novel class of small RNAs that are expressed specifically and abundantly in male germ cells. Here we report that the 3' termini of piRNAs are 2'-O-methylated; this modification may have important implications for the biogenesis and function of piRNAs.
Department of Pathology and Laboratory Medicine, Division of Neuropathology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
