BAG3 is a 575 amino acid protein that is found throughout the animal kingdom and homologs have been identified in plants. The protein is expressed ubiquitously but is most prominent in cardiac muscle, skeletal muscle, the brain and in many cancers. We describe BAG3 as a quintessential multi-functional protein. It supports autophagy of both misfolded proteins and damaged organelles, inhibits apoptosis, maintains the homeostasis of the mitochondria, and facilitates excitation contraction coupling through the L-type calcium channel and the beta-adrenergic receptor. High levels of BAG3 are associated with insensitivity to chemotherapy in malignant cells whereas both loss of function and gain of function variants are associated with cardiomyopathy.

中文翻译：

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BAG3：大自然的精髓多功能蛋白质作为普遍存在的细胞内胶水

BAG3 是一种 575 个氨基酸的蛋白质，在整个动物界中都有发现，并且在植物中已鉴定出同源物。该蛋白质普遍表达，但在心肌、骨骼肌、大脑和许多癌症中最为突出。我们将 BAG3 描述为一种典型的多功能蛋白质。它支持错误折叠蛋白质和受损细胞器的自噬，抑制细胞凋亡，维持线粒体的稳态，并促进通过 L 型钙通道和 β 肾上腺素能受体的兴奋收缩耦合。高水平的 BAG3 与恶性细胞对化疗不敏感有关，而功能丧失和功能获得变异都与心肌病有关。