MHC II分子（一种外周膜蛋白）的分选途径（或者合成途径）？请详细介绍，谢谢！

Question

介绍别的膜蛋白的分选途径也可，但必须是膜蛋白。

Answer 1

在合成的MHC II类的内质网中，α和β链多肽复合物生产和使用被称为特殊不变链 。 The nascent MHC class II protein in the rough ER has its peptide-binding cleft blocked by the invariant chain (Ii; a trimer) to prevent it from binding cellular peptides or peptides from the endogenous pathway (such as those that would be loaded onto class I MHC).新生的MHC II类雌激素受体蛋白中的粗有其肽结合裂的恒定链（二;一三聚体）阻断，以防止从内源性通路结合，比如那些将到类加载（蜂窝肽或多肽它本人MHC）的。

The invariant chain also facilitates the export of class II MHC from the ER to the golgi, followed by fusion with a late endosome containing endocytosed, degraded proteins.不变链也有利于从急诊室的MHC II类产品出口到高尔基体，紧随其后的融合晚内体含有吞噬，降解蛋白质。 The invariant chain is then broken down in stages by proteases called cathepsins , leaving only a small fragment known as CLIP which maintains blockage of the peptide binding cleft on the MHC molecule.当时的不变链细分阶段称为蛋白酶蛋白酶 ，只留下一个小片段被称为夹而维持阻塞分子的肽结合的MHC上裂。 An MHC class II-like structure, HLA-DM , facilitates CLIP removal and allows the binding of peptides with higher affinities. MHC II类的类结构， 人类白细胞抗原，糖尿病 ，方便夹删除，并允许更高的亲和力结合肽的。 The stable class II MHC is then presented on the cell surface. MHC II类的稳定，然后提出了关于细胞表面。