Transport vesicles are classified according to the components of the protein coat that surrounds them during their genesis and early life cycle of endocytosis. One of the most common and probably best-characterized classes of coated vesicles are Clathrin-coated vesicles (CCVs) that contain three protein layers. CCVs obtained their name because of the main component of the coat Clathrin, that forms a polymeric mechanical scaffold on the vesicle surface. The inner, membrane layer with its embedded cargo is linked to the outer Clathrin layer by a middle layer that consists of various clathrin-adaptor molecules and other proteins that have accessory/regulatory roles in CCV assembly. The classical key components of the majority of the cargos in Clathrin-dependent endocytosis are Adaptor-related protein complex 2 (AP complex 2) [1], [2], [3].

After the Clathrin lattice is formed, dynamins (e.g., Dynamin-2), endophilins (e.g., Endophilin B1), epsins (e.g. Epsin 1, Epidermal growth factor receptor pathway substrate 15 (Eps15)), amphiphysins (e.g., Bridging integrator 1 (BIN1 (Amphiphysin II)), Synaptosomal-associated protein, 91kDa homolog (AP180) all participate in the membrane invagination process and Clathrin rearrangements [4], [5], [6]. In addition, the plus-end motor Myosin I pulls the Dynamin-2 ring in the direction of the cell surface, while the minus-end motor Myosin VI pulls the coated bud into the cytosol. The resulting strain could then sever the constricted stalk beneath the dynamin ring [4].

Huntingtin interacting protein 1 (HIP1) and Huntingtin interacting protein 1 related (HIP12) both associates with Clathrin-coated vesicles, while the Actin cytoskeleton is involved in Clathrin vesicle transport [7], [8], [9].

1. Wendland B
   Epsins: adaptors in endocytosis? Nature reviews. Molecular cell biology 2002 Dec;3(12):971-7
2. Szymkiewicz I, Shupliakov O, Dikic I
   Cargo- and compartment-selective endocytic scaffold proteins. The Biochemical journal 2004 Oct 1;383(Pt 1):1-11
3. Edeling MA, Smith C, Owen D
   Life of a clathrin coat: insights from clathrin and AP structures. Nature reviews. Molecular cell biology 2006 Jan;7(1):32-44
4. Ungewickell EJ, Hinrichsen L
   Endocytosis: clathrin-mediated membrane budding. Current opinion in cell biology 2007 Aug;19(4):417-25
5. Schwartz CM, Cheng A, Mughal MR, Mattson MP, Yao PJ
   Clathrin assembly proteins AP180 and CALM in the embryonic rat brain. The Journal of comparative neurology 2010 Sep 15;518(18):3803-18
6. Zhuo Y, Ilangovan U, Schirf V, Demeler B, Sousa R, Hinck AP, Lafer EM
   Dynamic interactions between clathrin and locally structured elements in a disordered protein mediate clathrin lattice assembly. Journal of molecular biology 2010 Nov 26;404(2):274-90
7. Engqvist-Goldstein AE, Kessels MM, Chopra VS, Hayden MR, Drubin DG
   An actin-binding protein of the Sla2/Huntingtin interacting protein 1 family is a novel component of clathrin-coated pits and vesicles. The Journal of cell biology 1999 Dec 27;147(7):1503-18
8. Legendre-Guillemin V, Wasiak S, Hussain NK, Angers A, McPherson PS
   ENTH/ANTH proteins and clathrin-mediated membrane budding. Journal of cell science 2004 Jan 1;117(Pt 1):9-18
9. Carreno S, Engqvist-Goldstein AE, Zhang CX, McDonald KL, Drubin DG
   Actin dynamics coupled to clathrin-coated vesicle formation at the trans-Golgi network. The Journal of cell biology 2004 Jun 21;165(6):781-8