Plants tend to restrict their horizontal root proliferation in response to drought stress, an adaptive response mediated by the phytohormone abscisic acid (ABA) in antagonism with auxin through unknown mechanisms. Here, we found that stress-regulated miR393-guided cleavage of the transcripts encoding two auxin receptors, TIR1 and AFB2, was required for inhibition of lateral root growth by ABA or osmotic stress. Unlike in the control plants, the lateral root growth of seedlings expressing miR393-resistant TIR1 or AFB2 was no longer inhibited by ABA or osmotic stress. Our results indicate that miR393-mediated attenuation of auxin signaling modulates root adaptation to drought stress. © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This study was supported by the National Science Foundation (Grant #0446359) and USDA-NRI (Grant #2004-02111) (to L.X.) and partially by faculty startup funds from KAUST (to L.X.). The authors thank Dr. Zhenyu Wang for technical assistance.
ASJC Scopus subject areas
- Structural Biology
- Cell Biology
- Molecular Biology