Transgenerational inheritance of small RNAs challenges basic concepts of heredity. In C. elegans nematodes, small RNAs are transmitted across generations to establish a transgenerational memory trace of ancestral environments and distinguish self-genes from non-self-elements. Carryover of aberrant heritable small RNA responses was shown to be maladaptive and to lead to sterility. Here we show that various types of stress (starvation, high temperatures, and high osmolarity) induce resetting of ancestral small RNA responses and a genome-wide reduction in heritable small RNA levels. We found that mutants that are defective in various stress pathways exhibit irregular RNAi inheritance dynamics even in the absence of stress. Moreover, we discovered that resetting of ancestral RNAi responses is specifically orchestrated by factors that function in the p38 MAPK pathway and the transcription factor SKN-1/Nrf2. Stress-dependent termination of small RNA inheritance could protect from run-on of environment-irrelevant heritable gene regulation.
Sequencing data have been deposited in GEO under accession codes GSE129988
Stress Resets Transgenerational Small RNA InheritanceNCBI Gene Expression Omnibus, GSE129988.
A team of heterochromatin factors collaborates with small RNA pathways to combat repetitive elements and germline stress [ChIP-seq]NCBI Gene Expression Omnibus, GSE87522.
- Leah Houri Zeevi
- Guy Teichman
- Oded Rechavi
- Oded Rechavi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Kevin Struhl, Harvard Medical School, United States
© 2021, Houri Zeevi 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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