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A role for transcription from a piRNA cluster in de novo piRNA production.

ABSTRACT: PIWI-interacting RNAs (piRNAs) are at the heart of the nucleic acid-based adaptive immune system against transposons in animal gonads. To date, how the piRNA pathway senses an element as a substrate and how de novo piRNA production is initiated remain elusive. Here, by utilizing a GFP transgene, we screened and obtained clonal silkworm BmN4 cell lines producing massively amplified GFP-derived piRNAs capable of silencing GFP in trans. In multiple independent cell lines where GFP expression was silenced by the piRNA pathway, we detected a common transcript from an endogenous piRNA cluster, in which a part of the cluster is uniquely fused with an antisense GFP sequence. Bioinformatic analyses suggest that the fusion transcript is a source of GFP primary piRNAs. Our data implicate a role for transcription from a piRNA cluster in initiating de novo piRNA production against a new insertion.

SUBMITTER: Kawaoka S

PROVIDER: S-EPMC3264913 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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A role for transcription from a piRNA cluster in de novo piRNA production.

Kawaoka Shinpei S Mitsutake Hiroshi H Kiuchi Takashi T Kobayashi Maki M Yoshikawa Mayu M Suzuki Yutaka Y Sugano Sumio S Shimada Toru T Kobayashi Jun J Tomari Yukihide Y Katsuma Susumu S

RNA (New York, N.Y.) 20111222 2

PIWI-interacting RNAs (piRNAs) are at the heart of the nucleic acid-based adaptive immune system against transposons in animal gonads. To date, how the piRNA pathway senses an element as a substrate and how de novo piRNA production is initiated remain elusive. Here, by utilizing a GFP transgene, we screened and obtained clonal silkworm BmN4 cell lines producing massively amplified GFP-derived piRNAs capable of silencing GFP in trans. In multiple independent cell lines where GFP expression was si ...[more]

PMID: 22194309

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