Description
Arabidopsis ABA hpersensitive germination2-1 mutant shows an enhanced sensitivity to ABA. This mutant has higher levels of endogenous ABA. This mutant also exhibited SA hypersensitivity and dwarf phenotype. Regarding SA hypersensitivity, ahg2-1 exhibits higher endogenous SA level and an enhanced resistance to pathogenic bacteria. Since AHG2 encodes the Arabidopsis polyA specific ribonuclease that is involved in mRNA degradation, presumably abnormal accumulation of some mRNAs confers the unique phenotype. Transcriptome analyses are expected to offer information on the target of AHG2. In order to eliminate secondary effects of higher levels of ABA and SA, ahg2-1abi1-1 and ahg2-1sid2-2 double mutants were also examined. The transcriptome data revealed that; ahg2-1 confers unique gene expression profiles, ABA and SA affect the expression profiles of this mutant but many genes are independent of those plant hormone responses. Comparing with expression profiles of other mutants indicated that the ahg2-1 might affect mitochondrial function.