Protein and RNA Content and Synthesis in Embryos and Endosperms from Developing Triticum duram Seeds

Protein and RNA contents and synthesis were evaluated in the course of wheat grain (T. durum cv. Cappelli) development. Embryos and endosperms were considered separately during five phases from the 20th day after anthests until full ripenes was reached. No clean-cut changes were observed in the pattern of soluble proteins of the embryos. In the endosperms protein synthesis continues till the later phases and appears to be due to the albumin + globulin component. Screening of bands of endosperm proteins from electrophoresis indicates that the gliadins are synthesized early, with the exception of a Ω - gliadin. Glutelins with high relative molecular mass also appear to be synthesized when the grain approaches full ripeness. The RNA content of the embryo and the endosperm is high in the early stages, when high cell proliferation occurs, and declines later on. The synthesis of RNA during in vitro imbibition is, however, higher in the later phases of ripening. Most of RNA synthesized in the embryos was ribosomal.