OsABT, a Rice WD40 Domain-Containing Protein, Is Involved in Abiotic Stress Tolerance

Abstract

Plant growth and crop productivity are severely affected by abiotic stress on a global scale. WD40 repeat-containing proteins play a significant role in the development and environmental adaptation of eukaryotes. In this study, OsABT, a stress response gene, was cloned from rice (Oryza sativa L. cv. Nipponbare). OsABT encodes a protein containing seven WD40 domains. Expression analysis revealed that the OsABT gene was first up-regulated and then down-regulated following treatment with abscisic acid (ABA) and NaCl, but was down-regulated when treated with PEG8000. Subcellular localization results showed that OsABT was located in the cytoplasm and nucleus of Arabidopsis roots. OsABT transgenic Arabidopsis showed significantly increased tolerance to ABA and salt stress during plant seedling development. However, the transgenic lines were more sensitive to drought stress. Moreover, OsABT can interact with OsABI2, a component of ABA signaling pathway. These results showed that OsABT plays a positive regulatory role in response to salt stress and a negative role in response to drought stress in Arabidopsis.

Keywords

• abscisic acid
• Arabidopsis
• drought stress
• rice
• salt stress
• WD40 domain-containing protein