Poster: Late and Moved Abstracts

Abs # 961: Callose Synthase and Plant Development

Presenter:	Enns, Linda C, lenns@u.washington.edu
Authors	Enns, Linda C (A)   Cleland, Robert E (A)
Affiliations:	(A): University of Washington

Callose, a β-1,3-glucan, has been implicated in many aspects of plant development, including wounding, disease resistance, endosperm and pollen tube development, cell plate formation, general cell wall deposition, and intercellular communication. There is, however, a paucity of genetic evidence towards its specific involvement in these and other developmental processes. There are 12 putative callose synthase isoforms encoded by the Arabidopsis genome, 8 of which we have found to be expressed in the unwounded Arabidopsis root. We have used the reverse genetic strategy of TILLING (Targeting Induced Local Lesions IN Genomes) to identify several mutants containing a variety of amino acid substitutions in each of the 8 corresponding CalS proteins. In combination with T-DNA insertion mutants acquired from the Salk Institute Genomic Analysis Laboratory (SIGnaL), these mutants have begun to provide us with some evidence towards which CalS proteins are involved in which specific developmental roles. A specific amino acid change in CalS2 has been shown to cause early flowering and gross plant morphological effects, as well as to possibly change root symplastic domains. CalS11 and CalS12 have been shown to be redundant, and necessary to seed development. We are continuing to look at these mutants in more detail, as well as to explore the remainder of our mutant library.