Table 1.

Key EAPs and their effect on CCPs

					Function	Effect on CCP
Major coat proteins	CHC				Coat	KD ↓ initiation
	CLCa				Coat	KD ↓ initiation
	CLCb				Coat	KD ↓ initiation
	AP2				Adaptor	KD ↓ initiation
	Dyn1				GTPase	KO no effect; A: ↑ initiation and maturation
	Dyn2				GTPase	KD ↓ initiation
Easy arriving, pioneer proteins		FCHo1/2			Scaffold	KD ↓ initiation
		Eps15			Scaffold	KD ↓ maturation
		Intersectin			Scaffold	KD ↓ stabilization and maturation
		NECAP			Adaptor	KD ↓ maturation
		CALM			Adaptor	KD ↓ maturation
		Epsin			Adaptor	KD ↓ maturation
CCP maturation and fission			Amphiphysin		Curvature	ND
			Endophilin		Curvature	KD ↑ abortive
			N-WASP		Actin	ND
			Cortactin		Actin	ND
			Myosin 1E		Actin	ND
			Hip1R		Actin	ND
			SNX9		Scaffold	KD ↓ maturation
			Synaptojanin		Lipids	KD ↑ maturation
			PI3KC2α		Lipids	KD ↓ maturation
			PIP5K		Lipid	KD ↓ maturation OX ↑ initiation and maturation
Uncoating				GAK	Kinase	KD ↑ abortive
				Hsc70	ATPase	ND
				OCRL	Lipids	M: ↑ CCVs ↑ U-shaped CCPs

The effect on CCPs is summarized from several studies described herein. The graphic is adapted from Schmid (107). Abbreviations: A, activation; AP2, adaptor protein-2; CALM, clathrin assembly lymphoid myeloid leukemia; CCP, clathrin-coated pit; CHC, clathrin heavy chain; CLC, clathrin light chain; Dyn, dynamin; EAPs, endocytic accessory proteins; Eps15, EGF-receptor phosphorylation substrate; FCHo1/2, Fer/Cip4 homology domain-only proteins 1/2; GAK, cyclin G associated kinase; Hip1R, Huntingtin interacting protein-1 related; Hsc70, heat shock protein 70 kD; KD, knockdown; KO, knockout; M, mutation; ND, not determined; NECAP, adaptin-ear-binding coat-associated protein; N-WASP, neuralWiskott-Aldrich syndrome protein; OCRL, oculocerebrorenal Lowe syndrome protein; OX, overexpression; PI3KC2α, phosphatidylinositol 3-kinase C2α PIP, phosphatidylinositol phosphate; SNX9, sorting nexin 9.