Heat Shock in C. elegans Induces Downstream of Gene Transcription and Accumulation of Double-Stranded RNA

We observed that heat shock of Caenorhabditis elegans leads to the formation of nuclear double-stranded RNA (dsRNA) foci, detectable with a dsRNA-specific monoclonal antibody. These foci significantly overlap with nuclear HSF-1 granules. To investigate the molecular mechanism(s) underlying dsRNA foci formation, we used RNA-seq to globally characterize total RNA and immunoprecipitated dsRNA from control and heat-shocked worms. We find antisense transcripts are generally increased after heat shock, and a subset of both sense and antisense transcripts enriched in the dsRNA pool by heat shock overlap with dsRNA transcripts enriched by deletion of tdp-1, which encodes the C. elegans ortholog of TDP-43. Interestingly, transcripts involved in translation are over-represented in the dsRNAs induced by either heat shock or deletion of tdp-1. Also enriched in the dsRNA transcripts are sequences downstream of annotated genes (DoGs), which we globally quantified with a new algorithm. To validate these observations, we used fluorescence in situ hypridization (FISH) to confirm both antisense and downstream of gene transcription for eif-3.B, one of the affected loci we identified. Overall design: Total of 11 samples: 1 N2 heat shock input RNA input sample with 2 N2 heat shock J2 immunoprecipated samples. The following samples were re-analyzed from GSE61581. 3 tdp1 J2 immunoprecipitated samples and tdp1 total RNA input with 3 N2 J2 immunoprecipitated controls (with N2 input).