Differential expression of endophilin 1 and 2 dimers at central nervous system synapses

J Biol Chem. 2001 Nov 2;276(44):40424-30. doi: 10.1074/jbc.M106338200. Epub 2001 Aug 22.

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.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptor Proteins, Signal Transducing*
  • Amino Acid Sequence
  • Animals
  • Brain / metabolism*
  • Carrier Proteins / chemistry
  • Carrier Proteins / isolation & purification
  • Carrier Proteins / metabolism*
  • Protein Binding
  • Protein Isoforms / chemistry
  • Protein Isoforms / isolation & purification
  • Protein Isoforms / metabolism*
  • Rats
  • Synapses / metabolism*
  • src Homology Domains

Substances

  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • Protein Isoforms