Insulin-like Signaling Determines Survival During Stress via Post Transcriptional Mechanisms in C. elegans.

ABSTRACT: The insulin-like signaling (ILS) pathway regulates metabolism and is known to modulate adult lifespan in C. elegans. Altered stress responses and resistance to a wide range of stressors are also associated with changes in ILS and contribute to enhanced longevity. The transcription factors DAF-16 and HSF-1 are key effectors of the longevity phenotype. We demonstrate that increased intrinsic thermotolerance, due to lower ILS, is not dependent on stress induced HSF-1 transcriptional responses but instead requires active protein translation. Translation profiling experiments reveal genes that are post-transcriptionally regulated in response to altered ILS during heat shock in a DAF-16-dependent manner. Furthermore, several novel proteins are specifically required for ILS effects on thermotolerance. We propose that lowered-ILS results in DAF-16-induced metabolic and physiological changes that precondition a translational response to modulated survival under acute stress. 72 experimental samples were analyzed using custom oligo microarrays. A wild type sample pool was used as the Cy3 reference/control for all experimetal samples. All extracted RNA prior to array analysis was fractioned (via a sucrose gradient) based on ribosomal loading and pooled into ribosomal and free RNA (F1), light polysomes (F2) and heavy polysomes (F3) as described in the experimental procedures. The control RNAi is ‘empty’ vector L4440 RNAi feeding vector plasmid (1999 Firelab vector kit) transformed HT115(DE3), which was obtained from the Caenorhabditis Genetics Center (University of Wisconsin).

ORGANISM(S): Caenorhabditis elegans

SUBMITTER: Simon Melov 

PROVIDER: E-GEOD-22383 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress