Tang Yuehui, Bao Xinxin, Wang Shuang, Liu Yan, Tan Jie, Yang Mengxia, Zhang Mengyuan, Dai Rongrong, Yu Xinrong
Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou, China.
Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, Zhoukou Normal University, Zhoukou, China.
Front Plant Sci. 2019 Jul 17;10:942. doi: 10.3389/fpls.2019.00942. eCollection 2019.
Homeodomain-leucine zipper (HD-Zip) transcription factors are reported to play crucial roles in the growth, development, and stress responses of plants. However, there is little knowledge of the molecular mechanisms involved in physic nut's stress tolerance generally, or the functions of its genes. In the present study, a HD-Zip family transcription factor, designated , was isolated from physic nut. Expression profile analysis showed that salinity stress inhibited the expression of . Transient expression of JcHDZ07-YFP in protoplast cells revealed that JcHDZ07 was a nuclear-localized protein. Additionally, no obvious difference in growth and development between wild-type and -overexpressing plants was observed in the absence of stress. Our results further indicated that overexpressing transgenic plants had lower proline contents, lower survival rates, and activities of catalase and superoxide dismutase, but higher relative electrical leakage and malonaldehyde contents compared with wild-type plants under salinity stress conditions, suggesting that overexpression of confers enhanced sensitivity to salinity stress in transgenic . Expression of salt stress-responsive genes were upregulated in leaves of transgenic plants under salinity stress, but less strongly than in wild-type plants. Collectively, our results suggest that functions as an important regulator during the process of plant responses to salinity stress.
据报道，同源异型域亮氨酸拉链（HD-Zip）转录因子在植物的生长、发育和应激反应中发挥着关键作用。然而，关于麻风树的胁迫耐受性所涉及的分子机制，或者其基因的功能，人们普遍了解甚少。在本研究中，从麻风树中分离出一个HD-Zip家族转录因子，命名为 。表达谱分析表明，盐胁迫抑制了 的表达。JcHDZ07-YFP在原生质体细胞中的瞬时表达表明JcHDZ07是一种定位于细胞核的蛋白。此外，在无胁迫条件下，未观察到野生型和 过表达植株在生长发育方面有明显差异。我们的结果进一步表明，在盐胁迫条件下，与野生型植株相比， 过表达转基因植株的脯氨酸含量较低，存活率、过氧化氢酶和超氧化物歧化酶活性较低，但相对电导率和丙二醛含量较高，这表明 的过表达使转基因 对盐胁迫的敏感性增强。在盐胁迫下，转基因植株叶片中盐胁迫响应基因的表达上调，但上调程度低于野生型植株。总体而言，我们的结果表明， 在植物对盐胁迫的响应过程中起着重要的调节作用。
