The rde-1 gene, RNA interference, and transposon silencing in C. elegans.
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Forward genetic screens for mutants resistant to double-stranded-RNA-mediated interference defined the RNAi-deficient (rde) complementation groups in C. elegans, the screen that isolated rde-2 alongside rde-1 and rde-4.
"In order to study the interference process, we have selected C. elegans mutants resistant to dsRNA-mediated interference (RNAi)."
RDE-2 interacts with MUT-7 to mediate RNA interference in Caenorhabditis elegans.
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RDE-2 (F21C3.4 = rde-2/mut-8) was identified as a MUT-7-interacting protein by yeast two-hybrid, co-immunoprecipitation and re-localization; the MUT-7/RDE-2 complex acts downstream of primary siRNA production and upstream of target recognition, in the amplification step of RNAi.
"Together these data hint at a role for the MUT-7/RDE-2 complex in the amplification step of the RNAi pathway in C.elegans."
Empirically controlled mapping of the Caenorhabditis elegans protein-protein interactome network.
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High-throughput yeast two-hybrid interactome mapping reported an RDE-2 (Q19672) protein-protein interaction with MUT-7 (P34607).
"Empirically controlled mapping of the Caenorhabditis elegans protein-protein interactome network."
MUT-16 promotes formation of perinuclear mutator foci required for RNA silencing in the C. elegans germline.
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Each of the six mutator proteins (including RDE-2) localizes to perinuclear Mutator foci, punctate germline structures adjacent to but distinct from P granules that constitute an RNA-processing compartment for siRNA amplification with the RdRP RRF-1.
"each of the six mutator proteins localizes to punctate foci at the periphery of germline nuclei. The Mutator foci are adjacent to P granules"
MUT-7 exoribonuclease activity and localization are mediated by an ancient domain.
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Structural and biochemical study (crystal structure PDB 8Q66 of the MUT-7 CTD / MUT-8 CTD complex) showing RDE-2/MUT-8 binds the MUT-7 exoribonuclease via a worm-specific insertion in MUT7-C and thereby mediates MUT-7 recruitment to germ granules / Mutator foci.
"Caenorhabditis elegans MUT-7 contains a specific insertion within MUT7-C, which allows binding to MUT-8 and, consequently, MUT-7 recruitment to germ granules"
Distinct regions of the intrinsically disordered protein MUT-16 mediate assembly of a small RNA amplification complex and promote phase separation of mutator foci.
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MUT-16 is required for localization of RDE-2 (and other mutator proteins) to Mutator foci; RDE-2 in turn is required for MUT-7 localization, placing RDE-2 in a MUT-16 -> RDE-2 -> MUT-7 recruitment axis. Loss of any mutator complex protein abolishes RdRP-dependent secondary siRNAs.
"MUT-16 is required for localization of MUT-2, MUT-7, RDE-2, MUT-14, and MUT-15, all of which localize independently of one another except for MUT-7, which requires RDE-2 for localization"