细胞蛋白质量关系着生物的生存

<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋体">在衰老过程中生物维持蛋白质量的能力会逐渐下降，受损蛋白和错误折叠蛋白的累积起来会造成细胞死亡和细胞功能故障。阿尔茨海默症、帕金森症、亨廷顿舞蹈病等神经退行性疾病就与蛋白质控减弱有关。</font></span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">&nbsp;</span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋体">人多能干细胞能够无限复制同时维持未分化状态，这就需要避免蛋白体系有任何不平衡。帮助蛋白折叠的分子伴侣，在蛋白质控中起到了至关重要的作用。</font>TRiC/CCT<font face="宋体">复合体负责折叠大约</font><font face="Calibri">10%</font><font face="宋体">的细胞蛋白。</font></span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋体">我们通过研究多能干细胞的蛋白质控，发现这个复合体受到亚基</font>CCT8<font face="宋体">的调控。调节</font><font face="Calibri">CCT8</font><font face="宋体">可以在体细胞组织增强</font><font face="Calibri">TRiC/CCT</font><font face="宋体">复合体的装配和活性，进而延长线虫模型的寿命，延缓老年病的发生。</font></span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋体">这项研究表明，表达关键亚基</font>CCT8<font face="宋体">足以促进整个体系的装配，增强蛋白质量和延伸寿命。研究人员将在小鼠中测试自己的发现，希望进一步理解老年病，矫正与蛋白功能障碍有关的缺陷。</font></span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">&nbsp;</span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">线粒体是细胞内的能源工厂，负责为细胞提供必要能源，也在信号传导、细胞死亡和细胞生长中起关键作用。近年来，越来越多的证据将线粒体功能障碍与衰老、神经退行性疾病关联起来，比如阿尔茨海默症、帕金森病和亨廷顿舞蹈病。研究团队在杂志上发表文章指出，线粒体是大脑退化的关键。</span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">&nbsp;</span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">蛋白质形成往往需要分子伴侣的帮助，确保自己折叠成为正确的结构</span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">，</span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">不过，人们一直不清楚分子伴侣在膜蛋白成熟中起到了怎样的作用。去年九月，瑞士巴塞尔大学和苏黎世联邦理工的研究团队发现了分子伴侣的新功能。他们的研究显示，分子伴侣能够稳定未成熟的细菌膜蛋白，协助它插入到细菌的外膜。</span><span style="mso-spacerun:'yes';font-family:宋体;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>