Roles for the Yb body components Armitage and Yb in primary piRNA biogenesis in Drosophila.
PIWI-interacting RNAs (piRNAs) protect genome integrity from transposons. In Drosophila ovarian somas, primary piRNAs are produced and loaded onto Piwi. Here, we describe roles for the cytoplasmic Yb body components Armitage and Yb in somatic primary piRNA biogenesis. Armitage binds to Piwi and is required for localizing Piwi into Yb bodies. Without Armitage or Yb, Piwi is freed from the piRNAs and does not enter the nucleus. Thus, piRNA loading is required for Piwi nuclear entry. We propose that a functional Piwi-piRNA complex is formed and inspected in Yb bodies before its nuclear entry to exert transposon silencing.
Saito
Kuniaki
K
Keio University School of Medicine, Tokyo, Japan. siomim@sc.itc.keio.ac.jp
Ishizu
Hirotsugu
H
Komai
Miharu
M
Kotani
Hazuki
H
Kawamura
Yoshinori
Y
Nishida
Kazumichi M
KM
Siomi
Haruhiko
H
Siomi
Mikiko C
MC
D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004251:DNA Transposable Elements / Q000502:physiology; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000378:metabolism / Q000502:physiology*; D004722:Endoribonucleases / Q000378:metabolism; D021381:Protein Transport; D020365:RNA Helicases / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000096:biosynthesis*
D004251:DNA Transposable Elements; D029721:Drosophila Proteins; D034741:RNA, Small Interfering; C119416:fs(1)Yb protein, Drosophila; C484034:armi protein, Drosophila; D004722:Endoribonucleases; C521347:Zuc protein, Drosophila; D020365:RNA Helicases