Protein and RNA Synthesis in the Developing Endosperm

The process of endosperm development clearly involves the synthesis of many proteins, not only those enzymes involved in general cell metabolism and the synthesis of reserves, but also those proteins which are themselves laid down as storage material. Biosynthetic activity of the maize kernel increases from about the 8th day after anthesis up to about the 28th day (Fig. 3.5), after which it declines. The initial increase may, in part, be a reflection of increased enzyme synthesis within individual cells of the maize endosperm and in part an increase in the number of cells commencing protein synthesis as they approach 

An understanding of the mode and sequence of production of the components and factors affecting protein synthesis could be of considerable use to plant breeders and geneticists. Proteins of some seeds form an important part of the human diet in many countries, but are often deficient in certain amino acids, and if these are not provided from alternative food sources serious deficiency symptoms ensue. In normal maize, zein (the major protein body constituent) is poor in lysine and tryptophan, and is the protein which is synthesized late during maturation. Glutelins (the non-sequestered proteins) are synthesized 

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