klathrinbelagda

Klathrinbelagda is a term used in some Nordic-language scientific writings to describe clathrin-coated structures, particularly clathrin-coated pits and vesicles that form at the plasma membrane or the trans-Golgi network during clathrin-mediated trafficking.

Etymology and usage: The word combines klathrin (clathrin) and belagda (coated). In English-language literature the standard term is clathrin-coated vesicle or clathrin-coated pit; klathrinbelagda is a localized terminology, not a universal designation.

Structure and formation: Clathrin proteins assemble into triskelions that form a polyhedral lattice on the cytosolic surface of membranes. Adaptor protein complexes (such as AP-2 at the plasma membrane and AP-1 at the Golgi) recruit cargo receptors to the site of vesicle formation. Invagination and membrane scission produce a vesicle, with dynamin playing a key role in pinch-off. After scission, the clathrin coat is removed by chaperones such as Hsc70 and auxilin to yield a naked vesicle ready for fusion with early endosomes or other destinations.

Function and significance: This pathway mediates receptor-mediated endocytosis, uptake of nutrients, regulation of signaling receptors, and trafficking between organelles. It is essential for cellular nutrient uptake, cholesterol metabolism, and the regulation of many signaling pathways. Disruptions can affect cellular homeostasis and are studied in various diseases and in the context of viral entry.

See also: clathrin, clathrin-mediated endocytosis, vesicle trafficking.