We created CRISPR-Cas9 knock-out and overexpressing OsbZIP72 transgenic rice plants to gain a better understanding of the role and molecular mechanism of OsbZIP72 gene in stress tolerance, which has remained largely elusive. OsbZIP72 was expressed and integrated into rice transgenic plant genomes, and the OsbZIP72 transcript in overexpression lines was elicited by salinity, abscisic acid (ABA) and drought stresses. OsbZIP72 overexpressing plants showed higher tolerance to drought and salinity stresses, while knock-out transgenic lines showed higher sensitivity to these stresses. The differentially expressed genes (DEGs) from RNA-sequencing data encompassed several abiotic stress genes, and the functional classification of these DEGs demonstrated the robust transcriptome diversity in OsbZIP72. Yeast one-hybrid, along with luciferase assay, indicated that OsbZIP72 acted as a transcriptional initiator. Remarkably, electrophoresis mobility assay revealed that OsbZIP72 bound directly to the ABA- responsive element in the OsHKT1;1 promoter region and activated its transcription. Overall, our findings revealed that OsbZIP72 can act as a transcriptional modulator with the ability to induce the expression of OsHKT1;1 in response to environmental stress through an ABA-dependent regulatory pathway, indicating that OsbZIP72 can play a crucial role in the ABA-mediated salt and drought tolerance pathway in rice.

我们创建了CRISPR-Cas9基因敲除和过表达的OsbZIP72转基因水稻植物，以更好地了解OsbZIP72基因在胁迫耐受性中的作用和分子机制，而在很大程度上尚不清楚。表达OsbZIP72并将其整合到水稻转基因植物基因组中，盐度，脱落酸（ABA）和干旱胁迫诱导了OsbZIP72转录本在过表达系中的表达。OsbZIP72过表达的植物对干旱和盐分胁迫表现出更高的耐受性，而敲除的转基因品系对这些胁迫表现出更高的敏感性。来自RNA测序数据的差异表达基因（DEG）涵盖了几个非生物胁迫基因，这些DEG的功能分类显示了OsbZIP72中强大的转录组多样性。酵母一杂交，连同荧光素酶测定，表明OsbZIP72充当转录起始子。值得注意的是，电泳迁移率分析表明OsbZIP72直接与OsHKT1; 1启动子区域中的ABA响应元件结合并激活了其转录。总体而言，我们的发现表明，OsbZIP72可以作为转录调节剂，具有通过ABA依赖的调控途径响应环境胁迫而诱导OsHKT1; 1表达的能力，表明OsbZIP72在水稻介导的ABA介导的耐盐和干旱耐受性途径中起着至关重要的作用。