Gene expression profiling of C. elegans under various thermal conditions

To realistically evaluate the effects of the environment in space, it is necessary to understand the effects of external factors during sample transport from Earth to space. The present study focused on temperature, profiling the altered gene expression that develops under low cultivation temperatures in C. elegans, used as a space life science model. The 7903 genes were selected as differentially expressed genes, and divided into five sets with similar expression patterns using k-means clustering. Results from Gene Ontology analysis are significantly indicated that the cell cycle related genes, and the TGF?/insulin-like signal pathway related genes changed. The TGF?/insulin-like signal pathway is expected to be activated due to low temperatures, as well as by other stressors. To determine the genes whose expression changed four thermal conditions (10, 15, 20, and 25 ¡C), DNA microarray analysis was performed. The data consisted of 12 samples, consisting of three biological replicates at each temperature.