State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
Planta. 2012 Feb;235(2):433-41. doi: 10.1007/s00425-011-1477-x. Epub 2011 Sep 29.
Aldehyde dehydrogenase proteins consist of a superfamily and the family 7 (ALDH7) is a typical group with highly conserved proteins across species. It catalyzes oxidation of α-aminoadipic semialdehyde (AASA) in lysine degradation, participates in protection against hyperosmotic stress, and detoxifies aldehydes in human; however, its function in plants has been much less documented. Here we reported a mutant with yellow-colored endosperm in rice, and showed that the yellow endosperm was caused by mutation of OsALDH7. OsALDH7 is expressed in all tissues detected, with the highest level in mature seeds. We found that oryzamutaic acid A accumulated during late seed development and after a year-long storage in the colored endosperm, whereas it was undetectable in the wild type endosperm. Moreover, lysine degradation was enhanced in yeast over-expressing OsALDH7 and as a result, content of lysine, glutamate and saccharopine was changed, suggesting a role of OsALDH7 in lysine catabolism.
醛脱氢酶蛋白由一个超家族组成，家族 7（ALDH7）是一个具有高度物种间保守蛋白的典型群组。它催化赖氨酸降解中的α-氨基己二酸半醛（AASA）的氧化，参与对抗高渗胁迫，并在人体中解毒醛；然而，其在植物中的功能记录较少。在这里，我们报道了一个水稻中黄色胚乳的突变体，并表明黄色胚乳是由 OsALDH7 的突变引起的。OsALDH7 在所有检测到的组织中表达，在成熟种子中表达水平最高。我们发现，在有色胚乳中，oryzamutaic 酸 A 在种子发育后期和一年的储存后积累，而在野生型胚乳中则无法检测到。此外，在酵母中过度表达 OsALDH7 会增强赖氨酸降解，从而改变赖氨酸、谷氨酸和蔗糖的含量，表明 OsALDH7 在赖氨酸分解代谢中发挥作用。
