Pathway-specific canalization and plasticity of gene expression during C. elegans dauer development

Abstract

How robustness and plasticity—mechanisms that restrain or promote variation— interact to generate faithful developmental outcomes remains unclear. Caenorhabditis elegans development, where different environmental and genetic stimuli each can induce larvae to switch from continuous growth to a seemingly identical dauer (dormancy) state, provides a tractable model to explore this question. To identify dauer features that differ or are invariant, we compared gene expression of seven dauers generated by different dauer-inducing conditions, globally and within >100 sets of curated covarying genes or “modules” enriched for functional features such as “protein expression,” “mitochondria,” “germline,” etc., through gene co-expression network analyses. We found that most modules varied between dauers. Yet, a subset of modules associated with dormancy—DNA repair, cell cycle, and cell division— were invariant. We propose that the robust expression of genes that regulate a few core traits governing dormancy accommodates variation in others, supporting dauers’ adaptability and resilience.