CHLOROPLAST CHAPERONIN

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 绿色藻类和高等植物的叶绿体含有GroEL的同系物，称为伴侣蛋白（cpn）60，其在导入细胞器的蛋白质以及质体基因组编码的蛋白质的折叠中起作用。Cpn 60与GroEL的不同之处在于它由两种不同但同源的亚基α和β组成，它们具有大约50%的序列同一性。这两个亚基以大约1：1的化学计量发生，但它们在cpn 60十四聚体中的排列及其潜在的功能意义仍然不清楚。此外，cpn 60还与两个类似GroES的辅因子cpn 10和cpn 20协作。cpn 10在结构上对应于GroES，而cpn 20由含有cpn 10串联重复的亚基组成。我们建议使用cryo-EM来确定叶绿体伴侣蛋白的结构和没有基板。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The chloroplasts of green algae and higher plants contain a homolog of GroEL called chaperonin (cpn) 60 which functions in the folding of proteins imported into the organelles as well as of proteins encoded by the plastid genome. Cpn60 is distinct from GroEL in that it consists of two divergent but homologous types of subunit, alpha and beta, which share approximately 50% sequence identity. These two subunits occur at roughly 1:1 stoichiometry but their arrangement in the cpn60 tetradecamer and their potential functional significance has remained unclear. Moreover, cpn60 cooperates with two GroES-like co-factors, cpn10 and cpn20. Whereas cpn10 corresponds to GroES in architecture, cpn20 consists of subunits that contain a tandem repeat of cpn10. We propose to use cryo-EM to determine the structure of the chloroplast chaperonin with and without the substrate.