Argonautes ALG-3 and ALG-4 are required for spermatogenesis-specific 26G-RNAs and thermotolerant sperm in Caenorhabditis elegans

• DOI: 10.1073/pnas.0911685107
• Publication Date: 2010-02-05T03:34:56Z
• Authors: Colin C. Conine; Pedro J. Batista; Weifeng Gu; Julie M. Claycomb; Daniel A. Chaves; Masaki Shirayama; Craig C. Mello
• Keywords: 580; Male; 0301 basic medicine; 570; Hot Temperature; RNA-Binding Proteins; Spermatozoa; 03 medical and health sciences; Fertility; Mutation; Animals; RNA, Small Interfering; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Spermatogenesis

Gametogenesis is a thermosensitive process in numerous metazoans, ranging from worms to man. In Caenorhabditis elegans , a variety of RNA-binding proteins that associate with germ-line nuage (P granules), including the Piwi-clade argonaute PRG-1, have been implicated in maintaining fertility at elevated temperature. Here we describe the role of two AGO-class paralogs, alg-3 (T22B3.2) and alg-4 (ZK757.3), in promoting thermotolerant male fertility. A rescuing GFP:: alg-3 transgene is localized to P granules beginning at the late pachytene stage of male gametogenesis. alg-3 / 4 double mutants lack a subgroup of small RNAs, the 26G-RNAs which target and appear to down-regulate numerous spermatogenesis-expressed mRNAs. These findings add to a growing number of AGO pathways required for thermotolerant fertility in C. elegans and support a model in which AGOs and their small RNA cofactors function to promote robustness in gene-expression networks.