Immunological Analysis of δ-Crystallin Expressed in Various Tissues of the Chick in Vivo and in Vitro

Abstract

As δ-crystallin is considered to be a major marker protein for lens cell differentiation in birds, many results have been accumulated on how the gene of δ -crystallin is transcribed and translated during normal embryonic development as well as in in vitro lens cell differentiation. Besides the enormous expression in the lens itself, δ -crystallin gene has long been claimed to be expressed in extralenticular tissues of early embryos (e.g. Clayton et al., 1968). According to recent results, retina, brain and limb bud of the chick embryo contain mRNA of δ -crystallin (Agata et al.,1983), while in adenohypophysis of the early chick embryo, accumulation of the protein is observed (Barabanov, 1977). Through in vitro culture of dissociated cells, many tissues are reported to transdif- ferentiate and synthesize δ -crystallin, e. g. pigmented retina (Eguchi and Okada, 1973), neural retina (Okada et al. 1975), brain (Takagi et al., 1983), pineal body (Watanabe et al., 1985), and limb bud (Kodama and Eguchi, 1982)