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Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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PiRNA production requires heterochromatin formation in Drosophila

ABSTRACT: Here, we analyzed two small RNA libraries derived from ovarian tissue mutant for either the Drosophila SETDB1 gene, or the Bam gene. Here we show that deposition of histone 3 lysine 9 by the methyltransferase dSETDB1 (egg) is required for piRNA cluster transcription. In the absence of dSETDB1, cluster precursor transcription collapses in germline and somatic gonadal cells and TEs are activated, resulting in germline loss and a block in germline stem cell differentiation. We propose that heterochromatin protects the germline by activating the piRNA pathway. Keyword : Epigenetics 2 libraries were analyzed, with 1 being a developmental control (Bam Mutant).

ORGANISM(S): Drosophila melanogaster

SUBMITTER: Colin Malone

PROVIDER: E-GEOD-30086 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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piRNA production requires heterochromatin formation in Drosophila.

Rangan Prashanth P Malone Colin D CD Navarro Caryn C Newbold Sam P SP Hayes Patrick S PS Sachidanandam Ravi R Hannon Gregory J GJ Lehmann Ruth R

Current biology : CB 20110804 16

Protecting the genome from transposable element (TE) mobilization is critical for germline development. In Drosophila, Piwi proteins and their bound small RNAs (piRNAs) provide a potent defense against TE activity. TE targeting piRNAs are processed from TE-dense heterochromatic loci termed piRNA clusters. Although piRNA biogenesis from cluster precursors is beginning to be understood, little is known about piRNA cluster transcriptional regulation. Here, we show that deposition of histone 3 lysin ...[more]

PMID: 21820311

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