Poster: Late and Moved Abstracts

Abs # 1389: SOS pathway components in Thellungiella halophila

Presenter:	Pina, Francisco J., fjpina@u.arizona.edu
Authors	Pina, Francisco J. (A)   Monihan, Shea M (A)   Gerace, Julie M (A)   Zhu, Jian-Kang  (A)   Schumaker, Karen S (A)
Affiliations:	(A): University of Arizona

Plants have been classified based on their ability to grow in salt. Least adapted are glycophytes, plants that experience sharp reductions in growth even in low levels of salt. This category includes most of the important food, feed, fiber and ornamental crops grown world-wide. Halophytes are plants that are adapted to growth in salt. Within this group are plants that can sustain growth longer at higher levels of salt and those that require salt for optimal growth (euhalophytes). The glycophyte Arabidopsis thaliana has been developed as a genetic model for the study of salt tolerance ¨C research has focused on mutants of Arabidopsis that have increased salt-sensitivity when compared to wild type. From these studies in Arabidopsis, a Ca²⁺-dependent, phospho-regulatory pathway (Salt-Overly-Sensitive, SOS) for maintenance of cellular Na⁺ ion homeostasis and salt tolerance has been identified. An important question arising from studies with Arabidopsis is whether the salt tolerance elements, identified in a glycophyte, play a role in the response of halophytes to salt. To answer this question, we are taking a comparative approach using Arabidopsis and a salt tolerant (halophytic) relative, Thellungiella halophila. We have begun to characterize its growth in salt and the role of the SOS pathway in the adaptation of T. halophila to salt stress. The authors gratefully acknowledge support from the Western Alliance to Expand Student Opportunities and the Southwest Consortium on Plant Genetics and Water Resources.