Revealing Functional Crosstalk between Distinct Bioprocesses through Reciprocal Functional Tests of Genetically Interacting Genes

Summary: To systematically explore the genes mediating functional crosstalk between metazoan biological processes, we apply comparative genetic interaction (GI) mapping in Saccharomyces cerevisiae and Caenorhabditis elegans to generate an inter-bioprocess network consisting of 178 C. elegans GIs. The GI network spans six annotated biological processes including aging, intracellular transport, microtubule-based processes, cytokinesis, lipid metabolic processes, and anatomical structure development. By proposing a strategy called “reciprocal functional test” for interacting gene pairs, we discover a group of genes that mediate crosstalk between distinct biological processes. In particular, we identify the ribosomal S6 Kinase/RSKS-1, previously characterized as an mTOR (mechanistic target of rapamycin) effector, as a regulator of DAF-2 endosomal recycling transport, which traces a functional correlation between endocytic recycling and aging processes. Together, our results provide an alternative and effective strategy for identifying genes and pathways that mediate crosstalk between bioprocesses with little prior knowledge. : Chen et al. develop a “reciprocal functional test” to identify genes mediating crosstalk between different bioprocesses with little prior knowledge. With this method, ribosomal S6 Kinase/RSKS-1 is identified as a potential regulator of DAF-2 recycling. This finding traces a functional link between endocytic recycling and aging processes. Keywords: genetic interaction, bioprocess crosstalk, comparative mapping, endocytic recycling, RSKS-1/S6 Kinase, Caenorhabditis elegans, Saccharomyces cerevisiae, RAB-10/Rab10, recycling endosomes, mTOR