STUDIES ON STRUCTURAL HOMOLOGUES, PUTIDAREDOXIN REDUCTASE & APOPTOSIS INDUCING F

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。恶臭假单胞菌的腐胺还蛋白还原酶(PDR)和小鼠的细胞凋亡诱导因子(AIF)是两种结构同源的FAD酶，我们将用结晶学的方法来确定它们的三维结构，并研究它们的结构/功能关系。这两种黄素蛋白都有谷胱甘肽还原酶折叠，并具有双功能。PDR在细胞色素P450CaM单加氧酶中催化NADH到铁硫蛋白Putidaredosin的电子传递，但它也具有氧化还原活性的半胱氨酸，具有二硫醇/二硫化物氧化还原的功能。AIF是一种古老的哺乳动物死亡效应因子，不依赖于半胱氨酸天冬氨酸氨基转移酶(Caspase)，在诱导细胞凋亡时，它从其正常定位的线粒体膜间隙移位到细胞核，在那里它引起染色质凝聚和DNA片段化。该蛋白诱导细胞凋亡的生理功能和机制尚不清楚。我们的研究解决了PDR和AIF的结构与其催化功能之间的关系的问题。

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. A crystallographic approach will be used to determine three-dimensional structures and study structure/function relationships in two structurally homologous FAD-containing enzymes, putidaredoxin reductase (Pdr) from Pseudomonas putida and apoptosis inducing factor (AIF) from mice. Both flavoproteins have a glutathione reductase fold and are bifunctional. Pdr catalyzes electron transfer from NADH to an iron-sulfur protein, putidaredoxin, in cytochrome P450cam monooxygenase, but it also has redox active cysteines and can function as dithiol/disulfide oxidoreduction. AIF is a phylogenetically old mammalian, caspase-independent death effector which, upon apoptosis induction, translocates from its normal localization, the mitochondrial intermembrane space, to the nucleus where it causes chromatin condensation and DNA fragmentation. Neither physiological function nor mechanism of apoptosis induced by this protein is known. Our research addresses the question of how the structures of Pdr and AIF are related to their catalytic function.