BCL2 Family Protein Interactions In Cellular Survival States

 描述（由申请人提供）：BCL 2家族蛋白通过调节和影响细胞凋亡中线粒体外膜透化（MOMP）过程在细胞生命和死亡决定中发挥作用。该蛋白质家族还调节其他过程，独立于MOMP，如线粒体动力学，钙稳态，自噬和代谢。我们已经定义了典型和非典型BCL 2家族介导的细胞存活的不同“模式”。这些包括BCL 2效应物、BAX和巴克的直接激活物的隔离（模式1）和激活的效应物本身的隔离（模式2）。我们还表征了非典型效应物BOK，其不由抗凋亡BCL 2家族蛋白控制，而是由诱导其降解的ERAD途径控制。在这个更新申请中（代表我们对BCL 2家族研究的唯一支持），我们假设BCL 2蛋白阻止MOMP和凋亡的方式通过这些蛋白的其他MOMP独立作用影响细胞生理学。当生存机制受到干扰时，这反过来又影响MOMP和凋亡的过程。基于我们发表的和初步的结果，并使用新的方法在单细胞水平上询问事件，我们将问：1。经典BCL 2家族介导的存活的不同模式如何独立于MOMP影响细胞功能？在这里，我们将探讨不同模式的BCL 2家族的生存状态在活细胞中影响细胞的过程，独立于其控制MOMP的直接影响。特别是，我们将研究线粒体动力学，自噬，和钙稳态在内质网。2.经典BCL 2家族相互作用的不同模式如何整合细胞稳态和应激信号以促进细胞存活或细胞死亡？在这里，我们将探讨BCL 2家族蛋白控制的不同生存状态的作用和影响，以及它们的扰动如何导致MOMP和细胞死亡。通过这种方式，我们将确定BCL 2蛋白相互作用的生理效应如何影响抗凋亡BCL 2蛋白去抑制后的细胞死亡和存活。我们还将研究，在单细胞水平上，如何直接操纵BCL 2家族在活细胞中的相互作用影响细胞中的信号状态，持续压力。3.非经典BCL 2家族生存状态如何影响细胞生理学和细胞死亡？在这里，我们将研究BCL 2效应子BOK的功能。我们已经发现，BOK能够直接引起MOMP，但这种凋亡活性不能被抗凋亡BCL 2蛋白有效抑制。相反，它被ER相关降解（ERAD）途径的胞质臂抑制。将探讨不稳定和稳定的BOK对细胞凋亡、钙稳态和代谢的影响。我们的计划将形成一个新的，综合的了解BCL 2家族如何在细胞生理功能的基础。

 DESCRIPTION (provided by applicant): The BCL2 family proteins function in cell life and death decisions by regulating and affecting the process of mitochondrial outer membrane permeabilization (MOMP) in apoptosis. This protein family also regulates other processes, independently of MOMP, such as mitochondrial dynamics, calcium homeostasis, autophagy, and metabolism. We have defined different "modes" of canonical and non-canonical BCL2 family-mediated cell survival. These include sequestration of direct activators of the BCL2 effectors, BAX and BAK (Mode 1) and of the activated effectors themselves (Mode 2). We have also characterized a non-canonical effector, BOK, which is not controlled by anti-apoptotic BCL2 family proteins but rather by the ERAD pathway, which induces its degradation. In this renewal application (representing our only support for studies on the BCL2 family), we hypothesize that the ways in which the BCL2 proteins prevent MOMP and apoptosis impacts on cellular physiology via the other, MOMP-independent effects of these proteins. This, in turn, influences the process of MOMP and apoptosis when the survival mechanisms are perturbed. Based on our published and preliminary results, and using novel approaches to interrogate events at the single cell level, we will ask: 1. How do different modes of canonical BCL2 family-mediated survival impact cellular function independently of MOMP? Here we will explore how different modes of BCL2 family survival states in living cells affect cellular processes independently of their direct effects in controlling MOMP. In particular, we will examine mitochondrial dynamics, autophagy, and calcium homeostasis at the endoplasmic reticulum. 2. How do different modes of canonical BCL2 family interactions integrate cell homeostasis and stress signals to promote cellular survival or cell death? Here we will explore the roles and effects of different survival states controlled by BCL2 family proteins and how their perturbation leads to MOMP and cell death. In this way we will determine how the physiological effects of BCL2 protein interactions influences cell death and survival upon de-repression of the anti-apoptotic BCL2 proteins. We will also examine, at the single cell level, how directly manipulating BCL2 family interactions in living cells impacts on signaling states in cells that persist following stress. 3. How does a noncanonical BCL2 family survival state impact cellular physiology and cell death? Here we will investigate the functions of the BCL2 effector, BOK. We have found that BOK is capable of directly causing MOMP, but this apoptotic activity is not effectively inhibited by anti-apoptotic BCL2 proteins. Instead, it is inhibited by the cytosolic arm of the ER-associated degradation (ERAD) pathway. The effects of both unstable and stabilized BOK on apoptosis, calcium homeostasis, and metabolism will be explored. Our program will form the basis for a new, integrated understanding of how the BCL2 family functions in cell physiology.