Cautionary Notes on the Usage of abil-2 and abil-3 Mutants of Arabidopsis ABI1 for Functional Studies

Dear Editor, Abscisic acid （ABA） is a key hormone involved in plant growth and development, as well as stress adaptation. Recently, a core ABA signal pathway was proposed in which the ABA receptor proteins （PYR/PYL/RCAR） bind and inhibit type 2C protein phosphatases （PP2Cs） in the presence of ABA, which in turn releases the SnRK2s kinases, and the phosphorylated SnRK2s accumulate and subsequently phosphorylate the ABA-responsive element binding factors （Melcher et al., 2009; Cutler et al., 2010）.