Isolation of Arabidopsis mutants that have altered sensitivity to staurosporine and ABA

Abstract

We have developed a sensitive system to investigate the possible roles of protein phosphorylation in ABA signaling in Arabidopsis. We used staurosporine, a protein kinase inhibitor, to suppress the inhibitory effects of ABA on seed germination and the opening/greening of cotyledons. Using staurosporine, we performed a large genetic screen for asa (altered sensitivity to staurosporine and ABA) mutants and identified novel weak alleles of abi4 and abi5 mutants as asa1 and asa2 mutants. This method will be useful in isolating weak alleles of mutants and in selecting mutants with altered sensitivity to chemical compounds.