Kornilova E S
Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russia.
Biochemistry (Mosc). 2014 Sep;79(9):865-78. doi: 10.1134/S0006297914090041.
Receptor-mediated endocytosis is the most specific pathway for macromolecules and macromolecular complexes generally designated as ligands to enter cells. Upon binding to their transmembrane receptors, the ligands enter endocytic vesicles that fuse with each other giving rise to the so-called early endosomes. The sorting of ligand-receptor complexes internalized in these endosomes depends on their nature: metabolic receptors are recycled back to the plasma membrane, while signaling receptors and their ligands (e.g. receptor tyrosine kinases or receptors associated with tyrosine kinase) are delivered to internal vesicles of the multivesicular late endosomes and finally are degraded after interaction with lysosomes. During these processes, endosomes undergo translocation from the cell periphery to the juxtanuclear region, which is accompanied by multiple fusion, invagination, tabulation, and membrane fission events. This review considers modern concepts of the sorting mechanisms of ligand-receptor complexes, the crosstalk between endosomes, microtubules, and actin, and the role of this crosstalk in endosome maturation.
受体介导的内吞作用是大分子和通常被称为配体的大分子复合物进入细胞的最具特异性的途径。配体与跨膜受体结合后，进入内吞小泡，这些小泡相互融合，形成所谓的早期内体。内化于这些内体中的配体-受体复合物的分选取决于它们的性质：代谢受体被循环回质膜，而信号受体及其配体（如受体酪氨酸激酶或与酪氨酸激酶相关的受体）则被递送至多囊泡晚期内体的内部小泡，最终在与溶酶体相互作用后被降解。在这些过程中，内体从细胞周边向近核区域发生移位，这伴随着多次融合、内陷、平板化和膜裂变事件。本综述探讨了配体-受体复合物分选机制的现代概念、内体、微管和肌动蛋白之间的相互作用，以及这种相互作用在内体成熟中的作用。
