THE EXPRESSION OF BETA-GALACTOSE GENE IN THE TRANSGENIC EMBRYOS OF LOACH MISGURNUS-FOSSILIS L

In order to study the topological characteristics of transgene express ion in individuals, early loach embryos were injected with recombinant plasmid fragment, containing lacZ gene under the control of Raus sarc oma virus LTR. The expression of RSV-lacZ construct was found out in 8 0% of twenty-hours' embryos, 100% 2-3 days' embryos and 40% of 6-8 day s' frys. Point and dot expression was observes on the surface of the h ead, muscle segments, the yolk sac, in the yolk, on the caudal fin. Th e number, size and intensity of expression dots varied in defferent in dividuals and decreased in the course of embryo development. The prese nce of RSV-lacZ sequences was found in 57% of 19 days frys. The varieg ation causes of transgene expression are discussed.