AB15: A bZIP Protein Regulating ABA Response

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

The plant hormone abscisic acid (ABA) regulates many aspects of plant growth and development affecting crop productivity, including embryogenesis, water relations and tolerance of a variety of environmental stresses. Our long-term goal is to study the function and interaction of elements involved in response to ABA. One gene required for normal ABA response, the Arabidopsis ABA-insensitive 5 (ABI5) locus, has been identified by positional cloning in our lab and found to encode a protein with homology to the bZIP-domain class of transcription factors. The experiments outlined in this proposal will characterize the expression and biochemical function of ABI5, and investigate its interactions with other gene products in coordinating seed development and response to ABA. Our hypothesis is that ABI5 participates in seed- and/or ABA-regulation of gene expression, possibly in combination with other transcription factors. These studies should have general relevance to understanding the signaling network(s) regulating embryonic and hormonally regulated gene expression. Furthermore, they may have practical significance for potential manipulation of seed nutritional and storage qualities or vegetative stress tolerance.