Wang Xiaomin, Wu Rong, Shen Tongshu, Li Zhenan, Li Chengyong, Wu Bangkui, Jiang Hongye, Zhao Guangwu
The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang Agriculture and Forestry University, Hangzhou 311300, China.
The Agro-Tech Extension Center of Quzhou, 139 Fushi Road, Quzhou 324000, China.
Plants (Basel). 2022 Jan 5;11(1):139. doi: 10.3390/plants11010139.
MYB-type transcription factors play essential regulatory roles in seed germination and the response to seedling establishment stress. This study isolated a rice R2R3-MYB gene, , and functionally characterized its role in seed germination by generating transgenic rice plants with the overexpression and knockout of . Gene expression analysis suggested that was highly expressed in brown rice and root, respectively. Subcellular localization analysis determined that OsMYBAS1 was localized in the nucleus. No significant differences in seed germination rate were observed among wild-type (WT) and transgenic rice plants at the 0-cm sowing depth. However, when sown at a depth of 4 cm, higher germination rates, root lengths and seedling heights were obtained in -overexpressing plants than in WT. Furthermore, the opposite results were recorded between the mutants and WT. Moreover, -overexpressing plants significantly enhanced superoxide dismutase (SOD) enzyme activity and suppressed the accumulation of malondialdehyde (MDA) content at the 4-cm sowing depth. These results indicate that the MYB transcription factor OsMYBAS1 may promote rice seed germination and subsequent seedling establishment under deep-sowing conditions. These findings can provide valuable insight into rice seed-quality breeding to facilitate the development of a dry, direct-seeding production system.
MYB 类转录因子在种子萌发及对幼苗建立胁迫的响应中发挥着重要的调控作用。本研究分离出一个水稻 R2R3-MYB 基因，并通过构建该基因过表达和敲除的转基因水稻植株，对其在种子萌发中的作用进行了功能鉴定。基因表达分析表明，该基因分别在糙米和根中高表达。亚细胞定位分析确定 OsMYBAS1 定位于细胞核。在 0 厘米播种深度下，野生型（WT）和转基因水稻植株的种子萌发率未观察到显著差异。然而，当播种深度为 4 厘米时，过表达植株的萌发率、根长和幼苗高度均高于野生型。此外，突变体与野生型之间的结果相反。而且，过表达植株在 4 厘米播种深度下显著提高了超氧化物歧化酶（SOD）的酶活性，并抑制了丙二醛（MDA）含量的积累。这些结果表明，MYB 转录因子 OsMYBAS1 可能在深播条件下促进水稻种子萌发及随后的幼苗建立。这些发现可为水稻种子品质育种提供有价值的见解，以促进旱直播生产系统的发展。
