Robust Distal Tip Cell Pathfinding in the Face of Temperature Stress Is Ensured by Two Conserved microRNAS in Caenorhabditis elegans

摘要

Biological robustness, the ability of an organism to maintain a steady-state output as genetic or environmental inputs change, is critical for proper development. MicroRNAs have been implicated in biological robustness mechanisms through their post-transcriptional regulation of genes and gene networks. Previous research has illustrated examples of microRNAs promoting robustness as part of feedback loops and genetic switches and by buffering noisy gene expression resulting from environmental and/or internal changes. Here we show that the evolutionarily conserved microRNAs and (homolog of mammalian mir-29) contribute to the robust migration pattern of the distal tip cells in Caenorhabditis elegans by specifically protecting against stress from temperature changes. Furthermore, our results indicate that and may modulate the integrin signaling involved in distal tip cell migration by potentially targeting the GTPase and the beta-integrin . Our findings suggest a role for and in integrin-controlled cell migrations that may be conserved through higher organisms. They also provide yet another example of microRNA-based developmental robustness in response to a specific environmental stress, rapid temperature fluctuations.