Genes linked to normal development and survival of fish larvae

The present proposal combines the use of the newest retroviral-mediated trapping and mutagenesis techniques for zebrafish (Danio rerio) to investigate processes that are critical for growth and survival of fish larvae. Our research on the zebrafish model aims to study the development of essential physiological functions of the eye, hypothalamus, intestine, skin and gill. These tissues/organs are directly influenced by environmental factors and must respond to changes in the conditions by adjusting behavio ur and/or transport functions for ions and nutrients. Applying novel retroviral-mediated enhancer- and gene-trap methodology we will perform highly efficient large-scale identification of genes associated with development and physiology of specialized cel l types. The new transgenesis techniques also provide tools for mutagenesis, cell labelling and purification that will facilitate functional analysis. In this connection we will use microarray technology to determine cell specific gene expression profiles . Using quantitative PCR and microarrays we will also investigate how the various specialized cell types respond to changes in environmental conditions (e.g. salinity, nutrients, light, temperature). These studies will reveal fundamental knowledge about t he cell physiology and developmental regulation of tissues and organ systems of zebrafish larvae that will provide a basis for understanding the same processes in coldwater resource species (e.g. Atlantic salmon and cod). In addition, the retroviral-media ted screening will identify many transgenic lines in which the labelled cell types are associated with other processes of particular interest to aquaculture (e.g. muscle growth and sexual maturation). Overall we expect that the results generated from this research program will have a strong impact on future studies of fish biology in general, and will promote development of a sustainable aquaculture industry.