title: Differential expression of endophilin 1 and 2 dimers at central nervous system synapses.
abstract: Endophilin 1 is proposed to participate in synaptic vesicle biogenesis through SH3 domain-mediated interactions with the polyphosphoinositide phosphatase synaptojanin and the GTPase dynamin. Endophilin family members have also been identified as binding partners for a number of diverse cellular proteins. We define here the endophilin 1-binding site within synaptojanin 1 and show that this sequence independently and selectively purifies from brain extracts endophilin 1 and a closely related protein, endophilin 2. Endophilin 2, like endophilin 1, is highly expressed in brain, concentrated in nerve terminals, and found in complexes with synaptojanin and dynamin. Although a fraction of endophilins 1 and 2 coexist in the same complex, the distribution of these endophilin isoforms among central synapses only partially overlaps. Endophilins 1 and 2 are found predominantly as stable dimers through a predicted coiled-coil domain in their conserved NH2-terminal moiety. Dimerization may allow endophilins to link a number of different cellular targets to the endocytic machinery.
authors.affiliation: Howard Hughes Medical Institute and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
authors.forename: N
authors.initials: N
authors.lastname: Ringstad
authors.forename: Y
authors.initials: Y
authors.lastname: Nemoto
authors.forename: P
authors.initials: P
authors.lastname: De Camilli
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D011485:Protein Binding; D020033:Protein Isoforms / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D051381:Rats; D013569:Synapses / Q000378:metabolism*; D018909:src Homology Domains
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D020033:Protein Isoforms