摘要
Exogenous abscisic acid(ABA)can inhibit root growth and promote formation of more root hairs in the root tip of Arabidopsis.However,the molecular mechanisms that underlie root ABA signaling are largely unknown.We report here that hydrogen peroxide(H2O2)reduces the root growth of wild type, and the phenotype of H2O2 on the root growth is similar to ABA response.Meanwhile ABA-induced changes in the morphology of root system can be partly reversed by ascorbic acid in wild type and abolished in NADPH oxidase defective mutant atrbohF and atrbohC.Further,ABA can induce H2O2 accumulation in the root cells and enhance transcription level of OXI1,which is necessary for many more AOS-dependent processes such as root hair growth in Arabidopsis.Our results suggest that H2O2 as an important signal molecule is required for the ABA-regulated root growth and development in Arabidopsis.
Exogenous abscisic acid （ABA） can inhibit root growth and promote formation of more root hairs in the root tip of Arabidopsis. However, the molecular mechanisms that underlie root ABA signaling are largely unknown. We report here that hydrogen peroxide （H2O2） reduces the root growth of wild type, and the phenotype of H2O2 on the root growth is similar to ABA response. Meanwhile ABA-induced changes in the morphology of root system can be partly reversed by ascorbic acid in wild type and abolished in NADPH oxidase defective mutant atrbohF and atrbohC. Further, ABA can induce H2O2 accumulation in the root cells and enhance transcription level of OXI1, which is necessary for many more AOS-dependent processes such as root hair growth in Arabidopsis. Our results suggest that H202 as an important signal molecule is required for the ABA-regulated root growth and development in Arabidopsis.
基金
Supported by the National Natural Science Foundation of China(Grant Nos.30370765,30530430 and 30625005)
