9630622 Colasanti The id1 gene from maize has been partially cloned by transposon tagging and both the gene and the encoded protein product will be further characterized during this study. The gene is of interest because it has been genetically shown to be of critical importance in the switch of the corn plant from vegetative to reproductive growth. cDNA clones from different times of development will be isolated. The clones will be used to determine the RNA expression patterns of this gene with the goal of defining the timing and domain of action of the Id1 gene message. Antibodies to the Id1 protein will be produced and used to follow the expression pattern of the encoded protein during plant development and those patterns will be correlated with the mRNA patterns. Chimeric plants with sectors of normal and mutant tissue will be generated and examined to ascertain if the mutant phenotype can be corrected by adjacent normal tissue; i.e., whether Id1 regulates the synthesis of a diffusible product that is required for the transition to reproductive growth. %%% One of the most important events in the life cycle of higher plants is the transition from vegetative to reproductive growth. Although there is an abundance of information spanning decades that describes the physiological basis of the transition to flowering, very little is known about how this process is controlled at the molecular level. Further advancement in understanding this developmental mechanism will be achieved through the molecular and genetic characterization of genes that specifically mediate this transition. ***
