Smith D F
Department of Biochemistry and Molecular Biology, Mayo Clinic Scottsdale, Scottsdale, AZ 85259, USA.
Semin Cell Dev Biol. 2000 Feb;11(1):45-52. doi: 10.1006/scdb.1999.0350.
Studying the components, pathways, and dynamics of progesterone receptor (PR) assembly with chaperones has provided a highly valuable model system for understanding the coordinate actions of chaperones. Chaperones are primarily adapted to facilitate protein folding processes, and the actions of chaperones toward PR and other steroid receptors probably remain within this general functional boundary. Unlike a typical misfolded protein substrate, PR's folding is effectively arrested prior to hormone binding, thus extending indefinitely the chaperone-interaction phase that normally would be transitory during progressive protein folding. While one could consider this a limitation in PR's ability to fold properly, perhaps a more accurate view is that PR is specially adapted to remain 'misfolded', and thus extend chaperone interactions that function efficiently in repressing PR's transcriptional activity while the receptor awaits an activating signal.
研究孕激素受体（PR）与伴侣蛋白组装的组成成分、途径和动力学，为理解伴侣蛋白的协同作用提供了一个极具价值的模型系统。伴侣蛋白主要用于促进蛋白质折叠过程，其对PR和其他类固醇受体的作用可能仍在这一一般功能范围内。与典型的错误折叠蛋白质底物不同，PR的折叠在激素结合之前就有效地停止了，从而无限期地延长了伴侣蛋白相互作用阶段，而在蛋白质逐步折叠过程中，这个阶段通常是短暂的。虽然有人可能认为这是PR正确折叠能力的一个限制，但也许更准确的观点是，PR经过特殊适应而保持“错误折叠”状态，从而延长伴侣蛋白相互作用，在受体等待激活信号时，这种相互作用能有效地抑制PR的转录活性。
