Intergenerational transport of double-stranded RNA limits heritable epigenetic changes
Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
RNAs in circulation carry sequence-specific regulatory information between cells in plant, animal, and host-pathogen systems. Such RNA can cross generational boundaries, as evidenced by somatic double-stranded RNA (dsRNA) in the nematode C. elegans silencing genes of matching sequence in progeny. Here we dissect the intergenerational path taken by dsRNA from parental circulation and discover that cytosolic import through the dsRNA importer SID-1 in the parental germline and/or developing progeny varies with developmental time and dsRNA substrates. Loss of SID-1 enhances initiation of heritable RNA silencing within the germline and causes changes in the expression of the sid-1-dependent gene sdg-1 that last for more than 100 generations after restoration of SID-1. The SDG-1 protein is enriched in perinuclear Z granules required for heritable RNA silencing but is expressed from a retrotransposon targeted by such silencing. This auto-inhibitory loop reveals how retrotransposons could persist by hosting genes that regulate their own silencing.
