出版社：American Society for Biochemistry and Molecular Biology
摘要：Inorganic-32P, injected into yolks of eggs incubated to produce embryos of different ages, was incorporated into all phospholipid fractions in both whole chick embryo and embryo brain. Specific activity values compared between individual phospholipids of the same incubation age and in eggs injected at the same time did not vary more than twofold between one another. Biologically prepared phosphatidyl-32P choline and phosphatidyl-32P ethanolamine, when injected into yolks of eggs, gave a very different pattern of incorporation into embryo brain from that given by inorganic 32P. When the labeled choline phosphatide was injected, a phosphatidyl choline fraction was isolated whose specific activity was 30–40 times greater than those of other phospholipid fractions. Phosphatidyl-32P ethanolamine injection gave a qualitatively similar result. Glycerol-1,3-14C and acetate-1-14C were incorporated to a much lesser extent than inorganic-32P. The hypothesis is advanced that as the embryo develops, de novo synthesis from inorganic phosphate decreases and intact phospholipid is transferred from the yolk to the embryo and its organs.
