EVOLUTION OF J-PROTEINS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 生物体已经进化出一种特殊的、多组分的蛋白质系统，以确保正确的FES簇组装。该系统包括铁和S供体，铁/S簇组装的支架，以及促进铁/S簇转移过程的HSP70和J蛋白辅伴侣。虽然在大多数真核生物中，HSP70还参与其他过程，如蛋白质折叠和输入，但在细菌和一小部分真菌中，HSP70已进化为仅在Fe/S簇组装中发挥功能。作为分子共同进化的结果，这些生物中的J蛋白辅助伴侣也变得更加专门化。然而，这种专业化的确切性质尚不清楚。我们假设辅伴侣之间的结构差异是部分原因，并使用核磁共振波谱来确定和彻底比较具有普通Hsp70的生物体和具有特定Hsp70的生物体的J蛋白的结构。我们希望我们的研究结果将进一步支持我们的假设。

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. Organisms have evolved a specialized, multi-component protein system to ensure correct FeS cluster assembly. This system includes Fe and S donors, a scaffold for the Fe/S cluster assembly and an Hsp70 chaperone and a J protein cochaperone to facilitate the Fe/S cluster transfer process. While in most eukaryotes the Hsp70 also participates in other processes such protein folding and import, in bacteria and a small subset of fungi it has evolved to function in Fe/S cluster assembly only. As a result of molecular coevolution, the J protein cochaperone in these organisms also became more specialized. The exact nature of this specialization remains unknown however. We hypothesize that structural differences among the cochaperones are partly responsible and are using NMR spectroscopy to determine and thoroughly compare the structures of J proteins from an organism with a general Hsp70 and an organism with a specialized Hsp70. We hope the results of our studies will lend further support to our hypothesis.