Identification of novel compounds that inhibit SnRK2 kinase activity by high-throughput screening

Abscisic acid (ABA) is a major phytohormone that regulates abiotic stress responses and development. SNF1-rerated protein kinase 2 (SnRK2) key regulator of ABA signaling. To isolate compounds which directly affect SnRK2 activity, we optimized fluorescence-based system for high-throughput screening (HTS) regulators. Using this system, screened chemical library consisting 16,000 identified ten (INH1-10) as potential inhibitors. Further characterization these by in vitro phosphorylation assays confirmed three the were SnRK2-specific In contrast, seven inhibited ABA-responsive gene expression Arabidopsis cells. From results, INH1 was inhibitor vivo. We propose could be lead compound tools studying various plant species.