College of Plant Science, Jilin University, Changchun 130012, China.
Int J Mol Sci. 2023 Sep 15;24(18):14125. doi: 10.3390/ijms241814125.
Soybean ( (L.) Merr.) is an important source of plant protein, the nutritional quality of which is considerably affected by the content of the sulfur-containing amino acid, methionine (Met). To improve the quality of soybean protein and increase the Met content in seeds, soybean cystathionine γ-synthase 2 (), the first unique enzyme in Met biosynthesis, was overexpressed in the soybean cultivar "Jack", producing three transgenic lines (OE3, OE4, and OE10). We detected a considerable increase in the content of free Met and other free amino acids in the developing seeds of the three transgenic lines at the 15th and 75th days after flowering (15D and 75D). In addition, transcriptome analysis showed that the expression of genes related to Met biosynthesis from the aspartate-family pathway and S-methyl Met cycle was promoted in developing green seeds of OE10. Ultimately, the accumulation of total amino acids and soluble proteins in transgenic mature seeds was promoted. Altogether, these results indicated that plays an important role in Met biosynthesis, by providing a basis for improving the nutritional quality of soybean seeds.
大豆（（L.）Merr.）是植物蛋白的重要来源，其营养价值受含硫氨基酸蛋氨酸（Met）含量的影响较大。为了提高大豆蛋白的质量并增加种子中 Met 的含量，过量表达了 Met 生物合成的第一个特有酶——大豆胱硫醚γ-合酶 2（），在大豆品种“Jack”中产生了三个转基因系（OE3、OE4 和 OE10）。我们在开花后第 15 天（15D）和第 75 天（75D）检测到三个转基因系发育中的种子中游离 Met 和其他游离氨基酸的含量有显著增加。此外，转录组分析表明，OE10 中发育中的绿色种子中与天冬氨酸族途径和 S-甲基 Met 循环相关的 Met 生物合成基因的表达得到了促进。最终，转基因成熟种子中总氨基酸和可溶性蛋白质的积累得到了促进。总之，这些结果表明在 Met 生物合成中起着重要作用，为提高大豆种子的营养价值提供了依据。
