Heterochromatin-dependent transcription of satellite DNAs in the Drosophila melanogaster female germline
Abstract
Large blocks of tandemly repeated DNAs-satellite DNAs (satDNAs)-play important roles in heterochromatin formation and chromosome segregation. We know little about how satDNAs are regulated, however their misregulation is associated with genomic instability and human diseases. We use the Drosophila melanogaster germline as a model to study the regulation of satDNA transcription and chromatin. Here we show that complex satDNAs (>100-bp repeat units) are transcribed into long noncoding RNAs and processed into piRNAs (PIWI interacting RNAs). This satDNA piRNA production depends on the Rhino-Deadlock-Cutoff complex and the transcription factor Moonshiner—a previously-described non-canonical pathway that licenses heterochromatin-dependent transcription of dual-strand piRNA clusters. We show that this pathway is important for establishing heterochromatin at satDNAs. Therefore, satDNAs are regulated by piRNAs originating from their own genomic loci. This novel mechanism of satDNA regulation provides insight into the role of piRNA pathways in heterochromatin formation and genome stability.
Data availability
Sequencing data generated in this study have been deposited in NCBI Sequence Read Archive (SRA) under project accession PRJNA647441. Published sequencing data used in this study are from NCBI SRA database, and the full list of accession numbers can be found in Supplementary File 1.
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Heterochromatin-dependent transcription of satellite DNAs in the Drosophila melanogaster female germlineNCBI Sequence Read Archive, PRJNA647441.
Article and author information
Author details
Funding
National Institutes of Health (R35 GM119515)
- Amanda M Larracuente
University of Rochester (Stephen Biggar and Elisabeth Asaro fellowship)
- Amanda M Larracuente
University of Rochester (Messersmith Fellowship)
- Xiaolu Wei
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Detlef Weigel, Max Planck Institute for Developmental Biology, Germany
Version history
- Received: August 22, 2020
- Accepted: July 8, 2021
- Accepted Manuscript published: July 13, 2021 (version 1)
- Version of Record published: July 29, 2021 (version 2)
Copyright
© 2021, Wei et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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