Expression Levels of the γ-Glutamyl Hydrolase I Gene Predict Vitamin B9 Content in Potato Tubers
Expression Levels of the γ-Glutamyl Hydrolase I Gene Predict Vitamin B9 Content in Potato Tubers
复制标题
DOI：
10.3390/agronomy9110734
复制
发表时间：
2019-11
期刊：
影响因子：
--
通讯作者：
B. R. Robinson;Carolina García Salinas;Perla Ramos Parra;J. Bamberg;R. I. Díaz de la Garza;A. Goyer
中科院分区：
文献类型：
--
作者：
B. R. Robinson;Carolina García Salinas;Perla Ramos Parra;J. Bamberg;R. I. Díaz de la Garza;A. Goyer
主要作物叶酸的生物强化是帮助消除人类叶酸缺乏的重要策略。利用基因工程进行叶酸生物强化已在稻谷、番茄果实、生菜和马铃薯块茎中取得了巨大成功。然而，消费者的怀疑、司法障碍和缺乏经济模式阻碍了营养强化型基因工程（GE）粮食作物的广泛采用。与此同时，通过育种对粮食作物进行叶酸生物强化的努力却很少。之前我们报道过马铃薯基因型的叶酸含量存在 10 倍以上的变异。为了促进提高叶酸含量的育种，我们试图鉴定控制马铃薯块茎中叶酸含量的基因。为此，我们分析了低叶酸和高叶酸马铃薯基因型中叶酸生物合成和挽救基因的表达。首先，RNA-Seq 分析表明，在分析的所有叶酸生物合成和挽救基因中，只有一个编码 γ-谷氨酰水解酶 1 (GGH1) 的基因在玻利维茄 Dunal 种质的高叶酸分离子中始终以较高水平表达。其次，定量 PCR 显示，在分析的八对叶酸分离子中，有七对高叶酸分离子的 GGH1 转录水平高于低叶酸分离子。这些结果表明 GGH1 基因表达是马铃薯块茎中叶酸含量的指标。
Biofortification of folates in staple crops is an important strategy to help eradicate human folate deficiencies. Folate biofortification using genetic engineering has shown great success in rice grain, tomato fruit, lettuce, and potato tuber. However, consumers’ skepticism, juridical hurdles, and lack of economic model have prevented the widespread adoption of nutritionally-enhanced genetically-engineered (GE) food crops. Meanwhile, little effort has been made to biofortify food crops with folate by breeding. Previously we reported >10-fold variation in folate content in potato genotypes. To facilitate breeding for enhanced folate content, we attempted to identify genes that control folate content in potato tuber. For this, we analyzed the expression of folate biosynthesis and salvage genes in low- and high-folate potato genotypes. First, RNA-Seq analysis showed that, amongst all folate biosynthesis and salvage genes analyzed, only one gene, which encodes γ-glutamyl hydrolase 1 (GGH1), was consistently expressed at higher levels in high- compared to low-folate segregants of a Solanum boliviense Dunal accession. Second, quantitative PCR showed that GGH1 transcript levels were higher in high- compared to low-folate segregants for seven out of eight pairs of folate segregants analyzed. These results suggest that GGH1 gene expression is an indicator of folate content in potato tubers.