Abstract

Mulberry (Morus alba L.) is an economically and ecologically important plant with strong stress resistance. Glutamate dehydrogenase (GDH) can catalyze the reversible reaction of α-ketoglutarate and \({\text{NH}}_{4}^{ + }\) to glutamate, and plays an important role in resistance to adverse conditions. In this study, two MaGDH genes were cloned, and their biological characteristics studied. The results showed that the MaGDH1 and MaGDH2 protein were localized in the cell membrane, cytoplasm, chloroplasts, and MaGDH1 also localized in mitochondria. These proteins were expressed mainly in flowers. During seed germination, MaGDH1 and MaGDH2 expression levels were the highest when the radicle penetrated the seed coat. Stress tests suggested that MaGDH genes participate in responses to abiotic stress, and that the MaGDH2 protein had an inhibitory effect on the fungal pathogen Ciboria shiraiana, extracted from mulberry fruit. MaGDH overexpression in transgenic tobacco increased the solubility of proteins and chlorophyll content of transgenic tobacco, improving tolerance to salt and drought stresses.

中文翻译：

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桑树谷氨酸脱氢酶基因在桑树和转基因烟草中的表达与生物和非生物胁迫的关系

摘要

桑树（Morus alba L.）是一种具有重要抗逆性的经济和生态重要植物。谷氨酸脱氢酶（GDH）可以催化α-酮戊二酸和\（{\ text {NH}} _ {4} ^ {+} \）与谷氨酸的可逆反应，并且在抵抗不利条件方面起重要作用。在这项研究中，克隆了两个MaGDH基因，并对其生物学特性进行了研究。结果表明，MaGDH1和MaGDH2蛋白位于细胞膜，细胞质，叶绿体中，MaGDH1也位于线粒体中。这些蛋白质主要在花中表达。在种子发芽期间，MaGDH1和MaGDH2当胚根穿透种皮时，表达水平最高。压力测试表明，MaGDH基因参与了对非生物胁迫的响应，并且MaGDH2蛋白对从桑树果实中提取的真菌病原体雪梨（Ciboria shiraiana）具有抑制作用。MaGDH在转基因烟草中的过表达增加了蛋白质的溶解度和转基因烟草中的叶绿素含量，提高了对盐和干旱胁迫的耐受性。