Translation and codon usage regulate Argonaute slicer activity to trigger small RNA biogenesis [post]

Germano Cecere, Meetali Singh, Eric Cornes, Blaise Li, Piergiuseppe Quarato, Loan Bourdon, Florent Dingli, Damarys Loew, Simone Procaccia
2020 unpublished
In the Caenorhabditis elegans germline, thousands of mRNAs are concomitantly expressed with antisense 22G-RNAs, which are loaded into the Argonaute CSR-1. Despite their essential functions for animal fertility and embryonic development, how CSR-1 22G-RNAs are produced remains unknown. Here, we show that CSR-1 slicer activity is primarily involved in triggering the synthesis of small RNAs on the coding sequences of germline mRNAs and post-transcriptionally regulates a fraction of targets.
more » ... of targets. CSR-1-cleaved mRNAs prime the RNA-dependent RNA polymerase, EGO-1, to synthesize 22G-RNAs in phase with ribosome translation in the cytoplasm, in contrast to other 22G-RNAs mostly synthesized in germ granules. Moreover, codon optimality and efficient translation antagonize CSR-1 slicing and 22G-RNAs biogenesis. We propose that codon usage differences encoded into mRNA sequences might be a conserved strategy in eukaryotes to regulate small RNA biogenesis and Argonaute targeting.
doi:10.21203/ fatcat:abn2bymtv5fhpm4zrhtbdacmyy