The TRIM-NHL protein NHL-2 is a co-factor in the nuclear and somatic RNAi pathways in C. elegans
- Federation University, Australia
- University of Massachusetts Medical School, United States
- Monash University, Australia
- University of Toronto, Canada
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, United States
Abstract
Proper regulation of germline gene expression is essential for fertility and maintaining species integrity. In the C. elegans germline, a diverse repertoire of regulatory pathways promote the expression of endogenous germline genes and limit the expression of deleterious transcripts to maintain genome homeostasis. Here we show that the conserved TRIM-NHL protein, NHL-2, plays an essential role in the C. elegans germline, modulating germline chromatin and meiotic chromosome organization. We uncover a role for NHL-2 as a co-factor in both positively (CSR-1) and negatively (HRDE-1) acting germline 22G-small RNA pathways and the somatic nuclear RNAi pathway. Furthermore, we demonstrate that NHL-2 is a bona fide RNA binding protein and, along with RNA-seq data point to a small RNA independent role for NHL-2 in regulating transcripts at the level of RNA stability. Collectively, our data implicate NHL-2 as an essential hub of gene regulatory activity in both the germline and soma.
Data availability
All small RNA and mRNA Illumina sequencing data have been submitted to the NCBI's Sequence Read Archive (SRA), and are included under project accession number SRP115391.
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Caenorhabditis elegans Raw sequences reads NHL-2, Aug 12'17NCBI Sequence Read Archive, SRP115391.
Article and author information
Author details
Funding
National Health and Medical Research Council (606575)
- Peter R Boag
Canada Research Chairs (MOP-274660)
- Julie M Claycomb
Canadian Institutes of Health Research (MOP-125894)
- Quaid D Morris
- Timothy R Hughes
Connaught Fund
- Julie M Claycomb
National Institutes of Health (HD078253)
- Zhiping Weng
Canada Research Chairs (CAP- 783 262134)
- Julie M Claycomb
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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The TRIM-NHL protein NHL-2 is a co-factor in the nuclear and somatic RNAi pathways in C. elegans
eLife 7:e35478.
https://doi.org/10.7554/eLife.35478
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