[关键词]
[摘要]
玉米shrunken-2(sh2)突变体籽粒淀粉合成受阻,胚乳表现皱缩,蔗糖含量升高,成熟籽粒淀粉含量显著下降,但是sh2突变体中关于醇溶蛋白合成相关基因表达的研究较少报道。本文利用SDS-PAGE和荧光定量PCR详细研究sh2突变体籽粒胚乳发育不同时期醇溶蛋白的积累以及醇溶蛋白合成相关基因的表达情况。我们发现与郑58相比较,sh2中氨基酸组分变化与opaque2相似,赖氨酸含量升高,同时谷氨酸和亮氨酸含量下降。SDS-PAGE结果显示胚乳发育不同时期sh2中醇溶蛋白的积累均明显低于郑58,而且sh2中19kD α-醇溶蛋白积累明显减少。荧光定量PCR结果表明sh2突变体中对于Z1A、Z1B和Z1D家族基因的抑制较为显著。sh2突变体中PBF表达量升高,Opaque2表达下降。因此sh2突变体同时影响淀粉、氨基酸、贮藏蛋白等的代谢,深入研究将有助于碳氮代谢协同调控相关基因的挖掘。
[Key word]
[Abstract]
The synthesis of starch in the kernel of maize shrunken-2 (sh2) mutant is inhibited, resulting in wrinkled endosperm and increased sucrose content, while the starch content in mature kernels is significantly reduced. However, there are few reports on the expression of genes related to the synthesis of zein in sh2 mutants. In this study, SDS-PAGE and fluorescent quantitative PCR were used to investigate the accumulation of zein and the expression of genes related to their synthesis during different stages of endosperm development in sh2 mutant kernels. We found that the changes in amino acid composition in sh2 were similar to opaque2, with an increase in lysine content and a decrease in glutamic acid and leucine content compared to Zheng58. SDS-PAGE results showed that the accumulation of zein in sh2 at different stages of endosperm development was significantly lower than that in Zheng58, and the accumulation of 19kD α-zein in sh2 was significantly reduced. The results of fluorescent quantitative PCR showed that the inhibition of the Z1A, Z1B, and Z1D gene families was more significant in the sh2 mutant. The expression of PBF was increased in the sh2 mutant, while that of Opaque2 was decreased. Therefore, sh2 mutation affects the metabolism of starch, amino acids, and storage proteins, and further research will be helpful for exploring genes related to the coordinated regulation of carbon and nitrogen metabolism.
[中图分类号]
[基金项目]
河南省科技攻关项目(212102110279)