Analysis of Vascular Pattern Formation in Leaves of Arabidopsis

Yale University, New Haven CT

Investigators

Abstract

0110370 Nelson The components of leaf vascular pattern formation will be analyzed, using a molecular genetic approach in Arabidopsis. The formation of the leaf vascular pattern has developmental consequences beyond the simple siting of veins. Provascular sites in the leaf primordium, where the precursors of vein cells are formed, appear to serve as morphogenetic centers that regulate the location and specialization of vascular and other leaf cell types. This makes functional sense, since many of the cell types must function in cooperation with the veins, requiring a defined spatial relationship. Using forward and reverse genetic approaches, potential components of this process have been identified, including likely members of provascular signaling pathways. Their roles will be analyzed and additional candidates will be characterized. These are the aims: 1) To identify the immediate signaling pathway partners of the VH1 provascular receptor-like kinase, which is a candidate for a key role in organizing vascular regions. 2) To determine the role of the cvp1 sterol methyl transferase (SMT2) in provascular cell siting or differentiation. These processes are defective in cvp1 mutants. 3) To determine the role of the SAUR gene represented by the thick vein mutant. This may represent a direct link between auxin signals and vein formation. 4) To characterize the vein patterning roles of additional genes identified by mutants with vein pattern defects.