Genes for the oat storage proteins globulin and avenin are expressed in a differential manner during seed formation. The cause for this differential expression has been studied by Dr. Larkins as a component of his research on the biochemistry of seed storage proteins. Preliminary evidence has narrowed the control of expression to the translation step of the process. The investigators propose to explore the molecular basis for the differential synthesis of storage proteins in the oat system. They have constructed a series of transcription vectors encoding avenins and globulins and will analyze the translation of synthetic mRNAs in both wheat germ extracts and xenopus oocytes. This analysis may allow them to identify structural features of the mRNAs that cause the preferential translation of the globulin transcripts. They plan to prepare a tRNA-dependent in vitro translation system and assess the role of the tRNA population of oat endosperm in storage protein synthesis. This will allow them to determine if translation termination or protein transport play a critical role in regulating storage protein accumulation. A thorough knowledge of how storage protein synthesis is controlled will give us insight into the mechanisms regulating the growth and development of seeds and provide a basis for future improvements in the nutritional quality of oats and other cereals by genetic engineering.
