C. elegans orthologs MUT-7/CeWRN-1 of Werner syndrome protein regulate neuronal plasticity
Abstract
Caenorhabditis elegans expresses human Werner syndrome protein (WRN) orthologs as two distinct proteins: MUT-7, with a 3'-5' exonuclease domain, and CeWRN-1, with helicase domains. How these domains cooperate remains unclear. Here, we demonstrate the different contributions of MUT-7 and CeWRN-1 to 22G small interfering RNA (siRNA) synthesis and the plasticity of neuronal signaling. MUT-7 acts specifically in the cytoplasm to promote siRNA biogenesis and in the nucleus to associate with CeWRN-1. The import of siRNA by the nuclear Argonaute NRDE-3 promotes the loading of the heterochromatin-binding protein HP1 homolog HPL-2 onto specific loci. This heterochromatin complex represses the gene expression of the guanylyl cyclase ODR-1 to direct olfactory plasticity in C. elegans. Our findings suggest that the exonuclease and helicase domains of human WRN may act in concert to promote RNA-dependent loading into a heterochromatin complex, and the failure of this entire process reduces plasticity in postmitotic neurons.
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All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
Ministry of Science and Technology, Taiwan (103-2311-B-009 -003-MY2)
- Bi-Tzen Juang
Ministry of Science and Technology, Taiwan (105-2311-B-009 -002-MY3)
- Bi-Tzen Juang
National Institutes of Health (2R01DC005991)
- Noelle D L'Etoile
National Institutes of Health (R01DC015758)
- Noelle D L'Etoile
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Hsu 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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