T. Tobita et T. Ishimodatakagi, CHANGES OF TROPOMYOSIN ISOFORMS DURING DEVELOPMENT OF CROSS-FERTILIZED SEA-URCHIN EMBRYOS, Development, growth & differentiation, 38(2), 1996, pp. 209-219
Changes of tropomyosin isoforms during development of the sea urchin,
Hemicentrotus pulcherrimus, were investigated using two-dimensional ur
ea-shift gel electrophoresis. Tropomyosin isoforms included in the emb
ryos were gradually increased after 2 cell stage and retained at a con
stant level after gastrula stage. To detect the tropomyosin isoforms d
erived from zygotic genomes, embryos cross-fertilized between H. pulch
errimus and Pseudocentrotus depressus gametes were prepared. Since tro
pomyosin isoforms from H. pulcherrimus eggs and from P. depressus eggs
could be distinguished from each other on a two-dimensional electroph
oretic gel, the paternal isoforms of tropomyosin in the cross-fertiliz
ed embryos, which were not included endogenously in the egg, could be
regarded as products derived from zygotic genomes. The paternal isofor
ms of tropomyosin were detected first at around the gastrula stage in
embryos cross-fertilized between H. pulcherrimus sperm and P. depressu
s eggs and also in the reverse combination of the gamete species. Musc
le tropomyosins derived from H. pulcherrimus and P. depressus genomes
were similarly detected in cross-fertilized embryos at the pluteic sta
ge when the muscle tropomyosin appeared in sea urchin embryos.