Abstract
The receptor-like kinases are important components in the signal transduction pathway of various environmental and developmental signals. The RPK1, an LRR receptor kinase has been isolated from Arabidopsis, and its expression was induced by abscisic acid (ABA). We analyzed the phenotypes of T-DNA insertion mutants and antisense-transgenic plants for RPK1 to determine the function of RPK1 in ABA signaling. Repression of RPK1 expression in Arabidopsis decreased plant sensitivity to ABA during germination, growth, and stomatal closure; microarray and RNA gel analysis showed that many ABA-inducible genes are down-regulated in these plants. RPK1 is involved in the main ABA signaling pathway and in early ABA perception in Arabidopsis.
