Plant Genome IV Conference Plant Genome IV Conference
Fruit ripening is regulated by a combination of developmental, and hormonal stimuli. As such ripening represents a model system for analysis of plant developmental and hormonal signal transduction. Major emphasis in our laboratory has been placed on the genetic characterization and isolation of two loci which represent components of the developmental regulatory system controlling fruit ripening: ripening-inhibitor (rin), and non-ripening (nor). In order to understand the normal function of these genes, we are attempting to clone both loci using a genetic map-based gene isolation strategy. Chromosome walks to both Rin and Nor have resulted in isolation of YAC clones harboring each target gene. Progress toward development of cosmid contigs and fine mapping of target loci within the YAC clones will be presented. In addition we have initiated mapping experiments for two additional target loci involved in the hormone and light-regulated signal transduction pathways of fruit ripening. The high pigment (hp) mutant exhibits an exaggerated phytochrome response to light and influences pigment accumulation, while epinastic (epi) appears to be a mutant in a component of the ethylene signal transduction pathway. Progress toward isolation of targeted loci will be presented.