Pan Shujuan, Iannotti Michael J, Sifers Richard N
Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas, USA.
Methods Enzymol. 2011;499:1-16. doi: 10.1016/B978-0-12-386471-0.00001-8.
Biological checkpoints are known to function in the cellular nucleus to monitor the integrity of inherited genetic information. It is now understood that posttranslational checkpoint systems operate in numerous biosynthetic compartments where they orchestrate the surveillance of encoded protein structures. This is particularly true for the serpins where opposing, but complementary, systems operate in the early secretory pathway to initially facilitate protein folding and then selectively target the misfolded proteins for proteolytic elimination. A current challenge is to elucidate how this posttranslational checkpoint can modify the severity of numerous loss-of-function and gain-of-toxic-function diseases, some of which are caused by mutant serpins. This chapter provides a description of the experimental methodology by which the fate of a newly synthesized serpin is monitored, and how the processing of asparagine-linked oligosaccharides helps to facilitate both the protein folding and disposal events.
已知生物检查点在细胞核中发挥作用，以监测遗传信息的完整性。现在人们了解到，翻译后检查点系统在众多生物合成区室中发挥作用，在这些区室中，它们精心安排对编码蛋白质结构的监测。丝氨酸蛋白酶抑制剂（serpins）尤其如此，在早期分泌途径中，相互对立但又相互补充的系统发挥作用，最初促进蛋白质折叠，然后选择性地将错误折叠的蛋白质作为蛋白水解消除的目标。当前的一个挑战是阐明这种翻译后检查点如何改变许多功能丧失和功能毒性增加疾病的严重程度，其中一些疾病是由突变的丝氨酸蛋白酶抑制剂引起的。本章描述了监测新合成的丝氨酸蛋白酶抑制剂命运的实验方法，以及天冬酰胺连接的寡糖的加工如何有助于促进蛋白质折叠和处理过程。
