Weigel 9723823 Complementary molecular and genetic approaches will be used to identify and characterize new components in floral induction in Arabidopsis. Floral induction is the transition to flowering which is controlled by a poorly understood process involving at least three major pathways: a long-day dependent pathway, a gibberellin (GA)-dependent pathway and an autonomous pathway. Specifically a putative GA-response element in the prometer of the LEAFY gene, a critical component of flower initiation in Arabidopsis will be identified and characterized; new signal transduction factors in the GA-dependent floral induction pathway will be identified; new genes affecting floral induction will be sought through a gain-of-function screen and at least two of the genes identified in that screen will be characterized. One gene has already been found and characterized as a homolog of a known regulator of the LEAFY gene and that gene will be analyzed in detail. The importance of flowers for human sustenance cannot be overstated. They are organs of plant reproduction and their immediate products are fruits and seeds, including cereal grains, which provide the majority of calories consumed by humans. Thus, an understanding of how plants regulate the formation of flowers is likely to have long-ranging practical applications.
