, 2004 and Sunyer et al., 1995). Furthermore, three

“response to stress” genes all showed an increase in expression in southern barramundi compared with northern barramundi reared at 36 °C, lending further support to an occurrence of heightened stress in southern barramundi resulting in a comparative decrease in immune efficacy ( Fig. 4). Hspb2 was again shown to be significantly differentially expressed, along with heat shock protein 90 alpha (cystolic) class A member (Hsp90a.2) and proliferating cell nuclear antigen (Pcna). The Selleck ZVADFMK role of Hsp90a.2 in protecting the cell during heat stress has been well documented and Pcna is known to play a crucial role in nucleic acid metabolism and has been shown

to be involved in DNA repair as well as transcription, cell cycle regulation and hence growth (Feidantsis et al., 2009, Hermesz et al., 2001, Kelman, 1997 and Manchado et al., 2008). The expression of these genes indicates that in southern barramundi reared at warmer temperatures an increase in perceived stress is accompanied by an increase in stress protein gene expression and that this incidence of stress likely results in the suppression of the compliment component of the innate immune system in barramundi. The Enzalutamide order expression of genes from “microtubule based process” and “endopeptidase inhibitor activity” GO categories with supporting information from members of the “response to stress” GO category provides a more holistic picture of the phenotypic and cellular response of divergent barramundi populations to extremes in temperature. As many studies have demonstrated, the adaptive response of organisms, particularly that of fishes, is varied and not always consistent with what is predicted. Awareness of the underlying genetic mechanisms giving rise to the resulting phenotype would undoubtedly improve our knowledge of the nature of environmental adaptation and the various methods which it employs.

PRKD3 In the current study the growth of two genetically distinct populations of barramundi was compared at different temperatures and the major underlying genetic components of their growth response examined. Results show that southern populations of barramundi from a cool environment grow significantly better at cool water temperatures than northern populations of barramundi from a warmer environment, but that the reverse was not true for all barramundi grown at warm temperatures. The underlying genetics of the response of these barramundi populations to temperature reveals significant differences in the regulation of peptidase activity, namely compliment component 3 genes, and cytoskeletal tubulin genes associated with microtubule based process as indicated by the enrichment of significant gene ontologies.