From Pits to Plaques: Electron Microscopy Reveals Clathrin Structural Plasticity in Trafficking, Sorting and Adhesion

Abstract

Clathrin‐mediated trafficking has classically been described through the formation of curved clathrin‐coated pits and vesicles. However, growing evidence indicates that clathrin assembles into a diverse array of membrane‐associated architectures whose geometry, dynamics, and function vary across cellular compartments and physiological contexts. These include canonical coated pits at the plasma membrane and trans‐Golgi network, extended flat lattices and plaques at the cell surface, clathrin coats associated with endosomal sorting domains, and tubular clathrin assemblies associated with three‐dimensional migration. Here, we synthesize recent work, including cell‐type‐specific, mechanobiological, and ultrastructural studies, to propose clathrin structural plasticity as a core organizing principle of intracellular trafficking. We discuss how adaptor identity, membrane lipid composition, cytoskeletal coupling, and mechanical constraints collectively shape clathrin architectures, enabling a single coat system to support vesicular transport, cargo sorting, signaling, and adhesion.