The influence of donor nucleus source on the outcome of zebrafish somatic cell nuclear transfer.

The success of nuclear reprogramming following somatic cell nuclear transfer (SCNT) is thought to depend on factors present in the egg. Little is known about the role - if any - played by the somatic cell type on the outcome of the procedure. We tested whether cells of different lineages might have different capacities for reprogramming following SCNT, comparing cells isolated from five different tissues of transgenic zebrafish for their developmental potential when used as SCNT donor cells. We used transgenic zebrafish lines expressing green fluorescence protein under an endogenous tissue-specific promoter: HGn62A-skin, HGn28A-skin, HGn8E-heart, HG21C-fin and notochord and HGn30A-hatch gland. We analyzed the efficiency of cloning, as measured by reconstructed embryos that developed up to the hatched-fry stage. Specifically, donor cells of fin and notochord origin yielded the best rate of cloned fish production. All of the other cell types used were capable of producing cloned fish, albeit with significantly lower efficiency. These results indicate that the type of zebrafish cells used for SCNT can influence the outcome of the procedure. Future epigenetic analysis of these cells will help determine specific chromatin profiles in somatic cells that have an impact on nuclear reprogramming procedures.