Structure of the first C2 domain of synaptotagmin I: a novel Ca2+/phospholipid-binding fold

Cell. 1995 Mar 24;80(6):929-38. doi: 10.1016/0092-8674(95)90296-1.

Abstract

C2 domains are regulatory sequence motifs that occur widely in nature. Synaptotagmin I, a synaptic vesicle protein involved in the Ca2+ regulation of exocytosis, contains two C2 domains, the first of which acts as a Ca2+ sensor. We now describe the three-dimensional structure of this C2 domain at 1.9 A resolution in both the Ca(2+)-bound and Ca(2+)-free forms. The C2 polypeptide forms an eight-stranded beta sandwich constructed around a conserved four-stranded motif designated as a C2 key. Ca2+ binds in a cup-shaped depression between two polypeptide loops located at the N- and C-termini of the C2-key motif.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Binding Sites
  • Calcium / metabolism*
  • Calcium-Binding Proteins*
  • Conserved Sequence
  • Exocytosis
  • Liposomes
  • Membrane Glycoproteins / chemistry*
  • Membrane Glycoproteins / metabolism*
  • Models, Molecular
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Nerve Tissue Proteins / chemistry*
  • Nerve Tissue Proteins / metabolism*
  • Oligodeoxyribonucleotides
  • Phosphatidylcholines / metabolism
  • Phosphatidylserines / metabolism
  • Phospholipids / metabolism*
  • Protein Folding*
  • Protein Structure, Secondary*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Synaptic Vesicles / metabolism
  • Synaptotagmin I
  • Synaptotagmins

Substances

  • Calcium-Binding Proteins
  • Liposomes
  • Membrane Glycoproteins
  • Nerve Tissue Proteins
  • Oligodeoxyribonucleotides
  • Phosphatidylcholines
  • Phosphatidylserines
  • Phospholipids
  • Recombinant Proteins
  • Synaptotagmin I
  • Synaptotagmins
  • Calcium

Associated data

  • PIR/A48097
  • SWISSPROT/M72394
  • SWISSPROT/P05697
  • SWISSPROT/P08487
  • SWISSPROT/P09851
  • SWISSPROT/P21707
  • SWISSPROT/P22715
  • SWISSPROT/Q00722