Regulation of synaptic vesicle recycling by complex formation between intersectin 1 and the clathrin adaptor complex AP2.
Clathrin-mediated synaptic vesicle (SV) recycling involves the spatiotemporally controlled assembly of clathrin coat components at phosphatidylinositiol (4, 5)-bisphosphate [PI(4,5)P(2)]-enriched membrane sites within the periactive zone. Such spatiotemporal control is needed to coordinate SV cargo sorting with clathrin/AP2 recruitment and to restrain membrane fission and synaptojanin-mediated uncoating until membrane deformation and clathrin coat assembly are completed. The molecular events underlying these control mechanisms are unknown. Here we show that the endocytic SH3 domain-containing accessory protein intersectin 1 scaffolds the endocytic process by directly associating with the clathrin adaptor AP2. Acute perturbation of the intersectin 1-AP2 interaction in lamprey synapses in situ inhibits the onset of SV recycling. Structurally, complex formation can be attributed to the direct association of hydrophobic peptides within the intersectin 1 SH3A-B linker region with the "side sites" of the AP2 alpha- and beta-appendage domains. AP2 appendage association of the SH3A-B linker region inhibits binding of the inositol phosphatase synaptojanin 1 to intersectin 1. These data identify the intersectin-AP2 complex as an important regulator of clathrin-mediated SV recycling in synapses.
Institute of Chemistry and Biochemistry, Freie Universität and Charité Universitätsmedizin Berlin, 14195 Berlin, Germany.
Arndt
A
Pechstein
Jelena
J
Bacetic
Ardeschir
A
Vahedi-Faridi
Kira
K
Gromova
Anna
A
Sundborger
Nikolay
N
Tomlin
Georg
G
Krainer
Olga
O
Vorontsova
Johannes G
JG
Schäfer
Simen G
SG
Owe
Michael A
MA
Cousin
Wolfram
W
Saenger
Oleg
O
Shupliakov
Volker
V
Haucke
D033962:Adaptor Protein Complex 2 / Q000737:chemistry / Q000378:metabolism*; D033942:Adaptor Proteins, Vesicular Transport / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D004705:Endocytosis; D007798:Lampreys; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013572:Synaptic Vesicles / Q000378:metabolism*; D018909:src Homology Domains
D033962:Adaptor Protein Complex 2; D033942:Adaptor Proteins, Vesicular Transport; D009419:Nerve Tissue Proteins; C115919:intersectin 1; C097702:synaptojanin; D010744:Phosphoric Monoester Hydrolases