These authors contributed equally to this work.
The putative auxin efflux carrier OsPIN3t is involved in the drought stress response and drought tolerance
Article first published online: 15 OCT 2012
© 2012 The Authors. The Plant Journal © 2012 Blackwell Publishing Ltd
The Plant Journal
Volume 72, Issue 5, pages 805–816, December 2012
How to Cite
Zhang, Q., Li, J., Zhang, W., Yan, S., Wang, R., Zhao, J., Li, Y., Qi, Z., Sun, Z. and Zhu, Z. (2012), The putative auxin efflux carrier OsPIN3t is involved in the drought stress response and drought tolerance. The Plant Journal, 72: 805–816. doi: 10.1111/j.1365-313X.2012.05121.x
- Issue published online: 22 NOV 2012
- Article first published online: 15 OCT 2012
- Accepted manuscript online: 9 AUG 2012 10:23AM EST
- Received 30 December 2011; revised 28 July 2012; accepted 6 August 2012; published online 15 October 2012.
- auxin efflux carrier;
- drought stress;
- crown root;
- Oryza sativa
The phytohormone auxin plays a critical role in plant growth and development, and its spatial distribution largely depends on the polar localization of the PIN-FORMED (PIN) auxin efflux carrier family members. In this study, we identify a putative auxin efflux carrier gene in rice, OsPIN3t, which acts in auxin polar transport but is also involved in the drought stress response in rice. We show that OsPIN3t–GFP fusion proteins are localized in plasma membranes, and this subcellular localization changes under 1-N-naphthylphthalamic acid (NPA) treatment. The tissue-specific expression patterns of OsPIN3t were also investigated using a β-glucuronidase (GUS) reporter, which showed that OsPIN3t was mainly expressed in vascular tissue. The GUS activity in OsPIN3tpro::GUS plants increased by NAA treatment and decreased by NPA treatment. Moreover, knockdown of OsPIN3t caused crown root abnormalities in the seedling stage that could be phenocopied by treatment of wild-type plants with NPA, which indicated that OsPIN3t is involved in the control of polar auxin transport. Overexpression of OsPIN3t led to improved drought tolerance, and GUS activity significantly increased when OsPIN3tpro::GUS plants were subjected to 20% polyethylene glycol stress. Taken together, these results suggest that OsPIN3t is involved in auxin transport and the drought stress response, which suggests that a polar auxin transport pathway is involved in the regulation of the response to water stress in plants.