Proteome analysis of Oncorhynchus species during embryogenesis

To understand the molecular mechanisms underlying normal and abnormal devel opment of two salmonids, masu salmon (Oncorhynchus masou) and rainbow trout (O. mykiss), we used two-dimensional (2-D) electrophoresis to construct a series of 2-D maps during the embryonic period. We identified ail visible p rotein spots on the 2-D map by assigning numbers for masu salmon and rainbo w trout, and we determined N-terminal sequences of proteins for one hundred of the spots, that appear at very high concentrations in the whole embryos of masu salmon and rainbow trout. We also characterized embryonic stages a ccording to the periods of appearance of spots. Most of the N-terminal sequ ences were identical or at least highly similar to partial sequences report ed for vitellogenin (Vtg) of O. mykiss. A potential proteolytic processing of Vtg for rainbow trout is discussed in relation to the time of appearance and relative position of Vtg fragments within the complete protein sequenc e.