On March 27, Professor Chen Zhiming's team from the School of Basic Medicine of the University of South China published the latest research results entitled "VAMP8 function reveals tight linkage between endocytic recycling and endocytosis" in the international authoritative academic journal PNAS, revealing the close functional link between intracellular intracellular circulation and endocytosis. Professor Chen Zhiming of the University of South China and Sandra L. Schmid, Academician of the American Academy of Sciences, are the co-corresponding authors of this paper, and doctoral students Liu Ailing and Li Yueping of the University of South China School of Basic Medicine are the co-first authors.

Clathrin-mediated endocytosis (CME) is the main pathway for cytocytosis of macromolecular substances, such as nutrients and signaling receptors. Its dysfunction is closely related to cancer, neurodegenerative diseases, and cardiovascular disease. During CME, clathrins assemble on the cytoplasmic membrane to form clathrin-coated pits (CCPs), which are then invaged and detached from the plasma membrane to form clathrin-coated vesicles (CCVs) that are released into the cytoplasm.

Vesicle-Associated Membrane Protein 8 (VAMP8) has the function of regulating intracellular vesicle circulation, but it is unclear whether VAMP8-mediated intracellular vesicle transport is involved in regulating CME processes. Professor Chen Zhiming's team conducted in-depth research on this key scientific question and found that VAMP8 plays an important role in regulating CCP initiation, stabilization, and concaveness. Further mechanistic studies have shown that VAMP8 does not regulate CME by being directly recruited to CCV, but indirectly affects CME by promoting the circulation of endocytic goods (such as transferrin receptors) between the endosome and the plasma membrane.

This discovery closely links endocytosis and endosomal circulation for the first time, clarifies the importance of endosomal recycling in maintaining normal CME activity, reveals the interdependence mechanism between endocytosis and circulation, and provides a new perspective for understanding the dynamic regulation of cell membranes. In addition, this study provides a solid theoretical foundation for further exploration of the occurrence mechanism of related diseases and the search for potential intervention targets in the future.