Ap180

AP180 is a protein that plays an important role in clathrin-mediated endocytosis of synaptic vesicles. It is capable of simultaneously binding both membrane lipids (via an ANTH domain) and clathrin and is therefore thought to recruit clathrin to the membrane of newly invaginating vesicles. In Drosophila melanogaster (fruit flies), deletion of the AP180 homologue, leads to enlarged but much fewer vesicles and an overall decrease in transmitter release.^[1] In D. melanogaster it was also shown that AP180 is also required for either recycling vesicle proteins and/or maintaining the distribution of both vesicle and synaptic proteins in the nerve terminal. A ubiquitous form of the protein in mammals, CALM, (Clathrin-assembly lymphoid myeloid leukaemia protein) is named after its association with myeloid and lymphoid leukemias where some translocations map to this gene. The C-terminus of AP180 is a powerful and specific inhibitor of clathrin-mediated endocytosis.

More information is found on endocytosis.org.

See also

• Amphiphysin
• Epsin

Notes

1. Bao H, Daniels RW, MacLeod GT, Charlton MP, Atwood HL, Zhang B (2005). "AP180 maintains the distribution of synaptic and vesicle proteins in the nerve terminal and indirectly regulates the efficacy of Ca2+-triggered exocytosis". J. Neurophysiol. 94 (3): 1888–903. doi:10.1152/jn.00080.2005. PMID 15888532.

2. Zhang B, Koh YH, Beckstead RB, Budnik V, Ganetzky B, Bellen HJ (December 1998). "Synaptic vesicle size and number are regulated by a clathrin adaptor protein required for endocytosis". Neuron 21 (6): 1465–75. doi:10.1016/S0896-6273(00)80664-9. PMID 9883738.

3. Nonet ML, Holgado AM, Brewer F; et al. (July 1999). "UNC-11, a Caenorhabditis elegans AP180 homologue, regulates the size and protein composition of synaptic vesicles". Mol. Biol. Cell 10 (7): 2343–60. doi:10.1091/mbc.10.7.2343. PMC 25452. PMID 10397769.

References

• Ford MG, Pearse BM, Higgins MK; et al. (2001). "Simultaneous binding of PtdIns(4,5)P2 and clathrin by AP180 in the nucleation of clathrin lattices on membranes". Science 291 (5506): 1051–5. doi:10.1126/science.291.5506.1051. PMID 11161218.
• MMao Y, Chen J, Maynard JA, Zhang B, Quiocho FA (February 2001). "A novel all helix fold of the AP180 amino-terminal domain for phosphoinositide binding and clathrin assembly in synaptic vesicle endocytosis". Cell 104 (3): 433–40. doi:10.1016/S0092-8674(01)00230-6. PMID 11239400.