Ohta Masaru, Takaiwa Fumio
Functional Transgenic Crops Research Unit; Genetically Modified Organism Research Center; National Institute of Agrobiological Sciences; Tsukuba, Ibaraki, Japan.
Plant Signal Behav. 2014;9(3):e28194. doi: 10.4161/psb.28194. Epub 2014 Mar 10.
J-proteins are co-chaperone components of the HSP70 system. J-proteins stimulate Hsp70ATPase activity, which is responsible for stabilizing the interaction of Hsp70 with client proteins. J-proteins are localized in various intracellular compartments including the cytoplasm, mitochondria and endoplasmic reticulum (ER). Five types of ER resident J-proteins (ERdjs) have been found in plants (P58, ERdj2, ERdj2A, ERdj3B and ERdj7). Rice OsERdj3A is located in the vacuoleand protein storage vacuoles (PSV, PB-II) under conditions of ER stress. J-proteins that are localized to the vacuole or lysosome are not found in mammals and yeast, suggesting that the presence of OsERdj3A in the vacuole is plant-specific and one of the features unique to plant ERdjs. In this review, we summarize the current state of knowledge andrecent research advancements regarding plant ERdjs, and compare mammalian and yeast ERdjs with plant ERdjs.
J蛋白是HSP70系统的共伴侣成分。J蛋白刺激Hsp70ATP酶活性,该活性负责稳定Hsp70与客户蛋白的相互作用。J蛋白定位于包括细胞质、线粒体和内质网(ER)在内的各种细胞内区室。在植物中已发现五种内质网驻留J蛋白(ERdjs)(P58、ERdj2、ERdj2A、ERdj3B和ERdj7)。在ER应激条件下,水稻OsERdj3A位于液泡和蛋白储存液泡(PSV,PB-II)中。在哺乳动物和酵母中未发现定位于液泡或溶酶体的J蛋白,这表明OsERdj3A在液泡中的存在是植物特有的,也是植物ERdjs独有的特征之一。在这篇综述中,我们总结了关于植物ERdjs的当前知识状态和最新研究进展,并将哺乳动物和酵母的ERdjs与植物的ERdjs进行了比较。