Environmental Stresses on Protein Structure of the Repair Response in Higher Plan

在细菌、线虫、苍蝇、植物和哺乳动物(包括人类)中，细胞蛋白质损伤是通过蛋白质来对抗的。 修复反应。蛋白质L-异门冬氨酸(D-天冬氨酸)氧甲基转移酶催化蛋白质修复 通过甲酯化反应造成损害，该反应启动L-异天冬氨酸残基转化回正常的L- 天冬氨酸残留物。PIMT被认为有助于对抗衰老和氧化诱导的蛋白质损伤，但我们对 这种高度保守的酶是不完整的。为了进一步检验它的意义，这项研究将调查 PIMT活性在某些植物中的分子水平上发挥作用，以及它对整个生物体的影响。使用 利用生物化学方法，对重组拟南芥PIMT的活性进行亲和标记后的鉴定 从过表达的大肠杆菌细胞中提纯它。此外，当一个人或一个人对拟南芥的生物学影响 它的两个PIMT基因都被破坏了，将在商业化的T-DNA插入突变植物中进行分析，并 这些菌株就是从这些品种中培育出来的。由于光诱导氧化反应可能调节玉米PIMT的表达 (玉米)，将在强光下生长的玉米植株的匀浆中测量内源PIMT活性 条件。为了了解热带植物中的PIMT活动，这些植物面临着预期的自发伤害增加 在高温和光照条件下产生的香蕉内源PIMT活性将是 以相似的技术为特点的。总体而言，更好地了解PIMT酶可能有助于蛋白质的治疗 对人类的损害，也许是人类衰老表型的部分逆转。

Cellular protein damage is combated in bacteria, nematodes, flies, plants, and mammals, including humans, by protein repair reactions. Protein L-isoaspartate (D-aspartate) O-methyltransferase (PIMT) catalyzes the repair of protein damage via a methylesterification reaction, which initiates the conversion of L-isoaspartyl residues back to normal L- aspartyl residues. PIMT is thought to help fight age- and oxidation-induced protein damage, yet our understanding of this highly conserved enzyme is incomplete. To further examine its significance, this study will investigate the role PIMT activity plays in certain plants at the molecular level and its impact on the organism as a whole. Using a biochemical approach, the activity of recombinant Arabidopsis thaliana PIMT will be characterized after affinity-tag purifying it from overexpressing Escherichia coli cells. In addition, the biological impact on Arabidopsis when one or both of its PIMT genes are disrupted will be analyzed in commercially available T-DNA insertion mutant plants and strains bred from these. Since light induced oxidation reactions may regulate the expression of PIMT in Zea mays (corn), the endogenous PIMT activity will be measured in homogenates from corn plants grown under high light conditions. To understand PIMT activity in tropical plants, which face an expected increase in spontaneous damage generated by high temperature and light conditions, the endogenous PIMT activity in Musa acuminata (banana) will be characterized by similar techniques. Overall, a better understanding of PIMT enzyme may lead to treatments for protein damage in humans and perhaps the partial reversal of human aging phenotypes.