Tracer Studies on Chick Embryosin vitro

Abstract

In the experiments to be reported here isotopic tracer techniques were combined with the techniques of chick embryo culture in vitro and of organizer transplantations. The distribution of methionine taken up under these conditions was first tested by autoradiography; methionine was also used to label organizer grafts and observations were made on the derivatives from such grafts; finally, the transfer of labelled molecules from the grafts to the induced structures was to some extent investigated. The first use of radioactive tracers to investigate the transfer of substances in induction was by Waddington (1950), employing P32 on Amphibian embryos. Our experiments can be viewed as an extension of these investigations and those of Abercrombie & Causey (1950) and Islam (1953) who first used radioactive tracers to label embryonic grafts in chick embryos and explants respectively, and of Feldman & Waddington's (1955) work on the uptake of labelled methionine by the chick embryo in ovo.