1a.Objectives (from AD-416):
1) Develop homozygous clonal lines of rainbow trout resistant to bacterial and viral pathogens from previously developed transgenic trout and test disease resistance in outcrosses of different genetic background to evaluate protection.
2) Assess whether transgenic rainbow trout resistant to bacterial and viral pathogens are also resistant to infection by parasites (e.g., Ceratomyxa shasta and Chthyophthirius multifiliis).
3) Develop transgenic rainbow trout capable of accumulating astaxanthin in the flesh and identifying and charactering factors (genes) affecting this trait.
1b.Approach (from AD-416):
Using the disease resistant transgenic trout and the transgenic trout capable of accumulating higher levels of astaxanthin in the flesh as experimental models, we propose to identify and characterize specific pathways and genes leading to increased disease resistance and improved flesh color and nutritional quality.
By DNA microarray and real-time RT-PCR analyses we have identified many genes in four immune related pathways are upregulated in cecropin transgenic fish. Through repeated sperm-mediated gene transfer trails we have succeeded in producing 8 individuals that crtW and crtZ double transgenes. These fish will reach reproductive maturation by fall 2013. We will establish transgenic founder families in fall 2013 for subsequent characterization. Through challenge studies we have found that progeny of three heterozygous cecropin transgenic families were resistant to infection by Ceratomyxa shasta.