Qin Zhang, Yuqing Liu, Yingli Jiang, Aiqi Li, Beijiu Cheng, Jiandong Wu

Int J Mol Sci.; 2022 Aug 19;23(16):9340.  doi: 10.3390/ijms23169340.

Abstract

High salinity seriously affects crop growth and yield. Abscisic acid-, stress-, and ripening-induced (ASR) proteins play an important role in plant responses to multiple abiotic stresses. In this study, we identified a new salt-induced ASR gene in rice (OsASR6) and functionally characterized its role in mediating salt tolerance. Transcript levels of OsASR6 were upregulated under salinity stress, H₂O₂ and abscisic acid (ABA) treatments. Nuclear and cytoplasmic localization of the OsASR6 protein were confirmed. Meanwhile, a transactivation activity assay in yeast demonstrated no self-activation ability. Furthermore, transgenic rice plants overexpressing OsASR6 showed enhanced salt and oxidative stress tolerance as a result of reductions in H₂O₂, malondialdehyde (MDA), Na/K and relative electrolyte leakage. In contrast, OsASR6 RNAi transgenic lines showed opposite results. A higher ABA content was also measured in the OsASR6 overexpressing lines compared with the control. Moreover, OsNCED1, a key enzyme of ABA biosynthesis, was found to interact with OsASR6. Collectively, these results suggest that OsASR6 serves primarily as a functional protein, enhancing tolerance to salt stress, representing a candidate gene for genetic manipulation of new salinity-resistant lines in rice.

See https://pubmed.ncbi.nlm.nih.gov/36012605/

Figure 1: Expression profiles of OsASR6. Inducible expression pattern of OsASR6 in (A) the roots and (B) the shoot under ABA, H₂O₂, and NaCl stresses treatment. Rice Actin1 was used as an internal control for qRT-PCR analysis. Asterisks indicate significant difference compared to the transcription level of 0 h groups. Three independent experiments were performed. Data represent means ± SD. * p < 0.05, ** p < 0.01.