Department of Genetics, University of Melbourne, Parkville, Victoria 3010, Australia.
Plant Biol (Stuttg). 2011 Jul;13(4):693-7. doi: 10.1111/j.1438-8677.2011.00464.x. Epub 2011 Apr 28.
Glutathione (GSH) biosynthesis-deficient gsh1 and gsh2 null mutants of Arabidopsis thaliana have late embryonic-lethal and early seedling-lethal phenotypes, respectively, when segregating from a phenotypically wild-type parent plant, indicating that GSH is required for seed maturation and during germination. In this study, we show that gsh2 embryos generated in a partially GSH-deficient parent plant, homozygous for either the cad2 mutation in the GSH1 gene or homozygous for mutations in CLT1, CLT2 and CLT3 encoding plastid thiol transporters, abort early in embryogenesis. In contrast, individuals homozygous for the same combinations of mutations but segregating from heterozygous, phenotypically wild-type parents exhibit the parental gsh2 seedling-lethal phenotype. Similarly, homozygous gsh1 embryos generated in a gsh1/cad2 partially GSH-deficient parent plant abort early in development. These observations indicate that the development of gsh1 and gsh2 embryos to a late stage is dependent on the level of GSH in the maternal plant.
谷胱甘肽（GSH）生物合成缺陷的 gsh1 和 gsh2 拟南芥缺失突变体在从表型野生型亲本植物中分离时分别表现出晚期胚胎致死和早期幼苗致死表型，表明 GSH 是种子成熟和萌发所必需的。在这项研究中，我们表明，在部分 GSH 缺乏的亲本植物中产生的 gsh2 胚胎，要么是 GSH1 基因中的 cad2 突变的纯合子，要么是编码质体硫转运蛋白的 CLT1、CLT2 和 CLT3 突变的纯合子，在胚胎发生早期就会流产。相比之下，同样的突变组合但从杂合、表型野生型亲本中分离出来的个体则表现出亲本 gsh2 幼苗致死表型。同样，在 gsh1/cad2 部分 GSH 缺乏的亲本植物中产生的 gsh1 胚胎在发育早期就会流产。这些观察结果表明，gsh1 和 gsh2 胚胎发育到晚期阶段依赖于母体植物中 GSH 的水平。
