Since most of the expression changes took place within three days and resulted in the differential expression of a considerable number of probes, an initial overview of the major pro selleck screening library cesses involved was conducted before a more detailed gene by gene analysis. Overview of expression profiles via GO enrichment and Ingenuity pathway analysis Microarray probes were classified according to their Gene Ontology terms in order to determine whether particular biological processes were enriched in response to the different treatments. Overall, 25. 3% of the probes were associated with at least a GO term. The most represented Biological Processes on the microarray were cellular processes, regula tion of biological process, response to stimulus and multi cellular organismal development.

Interestingly, when GO enrichment analysis was performed on differentially expressed genes from different comparisons, no particular Biological Process term was enriched amongst the up regulated gene lists with the exception of cellular processes between the STWS and the ST groups. The down regu lated gene lists revealed a significant reduction in meta bolic processes, indicating that the animals were repartitioning their translation machinery away from normal housekeeping functions towards repair and regeneration. This conclusion is sub stantiated by the Ingenuity pathway analysis software results which identified the main molecular and cellular biological functions that were significantly affected and also which physiological systems with regard to development and function were involved.

The IPA top networks for all the comparisons which included animals with scales removed produced matches to cancer, indicating that genes which have been implicated in non controlled cell proliferation in human may be involved in normal cellu lar proliferation in fish skin. Not surprisingly the top networks also included those involved in the cell cycle, cellular growth and proliferation, and biological pro cesses included tissue organ development and morphol ogy and haematopoiesis. Lipid metabolism was one of the most significant functions represented in IPA in the fasted fish indicating the effects of nutrient depletion on the general metabolism of the animals. This finding Drug_discovery was substantiated in the STWS comparisons, which also included networks involved in vitamin and mineral metabolism. The Ingenuity results, whilst providing an overview of the main cellular processes affected in the experiments, provide more detail than the simplified GO enrichment analyses and link in far more directly to analysis of individual genes and their putative functional identification.