Analyses of disease resistance mechanism by rice acyltransferase family

OsAT1是从水稻斑叶18突变体中分离得到的一个酰基转移酶基因。过表达OsAT1的水稻表现出稻瘟病抗性。在这项研究中，我们还发现这些植物具有抗枯萎病的能力。虽然野生型植物中OsAT1的转录不受blast感染的影响，但我们观察到两个OsAT家族成员（OsAT15和OsAT180）的转录水平升高。其他11个OsAT家族成员的转录率未受显著影响。OsAT15主要在幼穗中转录，而在野生型植株的叶片、穗和根中均未检测到。我们制备了过表达OsAT15的水稻植株，并进行了抗稻瘟病试验。但它们没有表现出抗爆炸能力。我们通过测定过表达OsAT1水稻的脂肪酸含量来确定osat的生化功能。我们发现这些植物的亚油酸含量增加了。OsAT1和OsAT15编码的蛋白在带有His-tag的大肠杆菌中过量产生。过量生产的蛋白质是不溶的，所以我们现在正试图找到使它们可溶的方法。同时，我们正在制作过表达OsAT1或OsAT15to的转基因拟南芥进行代谢组学分析。

OsAT1 is a rice acyltransferase gene isolated from the spotted leaf 18 mutant that was generated by activation tagging in rice. Rice plants overexpressing OsAT1 showed blast resistance. In this research, we also found that these plants have blight resistance. Although transcription of OsAT1 was not affected by blast infection in wild-type plants, we observed elevated transcript levels of two OsAT family members (OsAT15 and OsAT180). Transcription rates of the other eleven OsAT family members were not remarkably affected. OsAT15 was transcribed mainly in the young panicle, but it was not detected in the leaf blade, panicle and root of the wild-type plant. We generated rice plants overexpressing OsAT15 and performed blast resistance test. But they did not show blast resistance.We measured the fatty acid content of rice overexpressing OsAT1 to determine the biochemical function of OsATs. We found that the content of linoleic acid increased in these plants. The proteins coded by OsAT1 and OsAT15 were overproduced in E.coli with His-tag. The overproduced proteins were insoluble, so we are now trying to find ways to make them soluble. Simultaneously, we are making transgenic Arabidopsis overexpressing OsAT1 or OsAT15to for metabolome analysis.