A presynaptic inositol-5-phosphatase

Nature. 1996 Jan 25;379(6563):353-7. doi: 10.1038/379353a0.


Synaptojanin is a nerve terminal protein of relative molecular mass 145,000 which appears to participate with dynamin in synaptic vesicle recycling. The central region of synaptojanin defines it as a member of the inositol-5-phosphatase family, which includes the product of the gene that is defective in the oculocerebrorenal syndrome of Lowe. Synaptojanin has 5-phosphatase activity and its amino-terminal domain is homologous with the yeast protein Sac1 (Rsd1), which is genetically implicated in phospholipid metabolism and in the function of the actin cytoskeleton. The carboxy terminus, which is of different lengths in adult and developing neurons owing to the alternative use of two termination sites, is proline-rich, consistent with the reported interaction of synaptojanin with the SH3 domains of Grb2 (refs 1, 2). Synaptojanin is the only other major brain protein besides dynamin that binds the SH3 domain of amphiphysin, a presynaptic protein with a putative function in endocytosis. Our results suggest a link between phosphoinositide metabolism and synaptic vesicle recycling.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Brain / enzymology
  • Cell Line
  • Cloning, Molecular
  • DNA, Complementary
  • Molecular Sequence Data
  • Nerve Tissue Proteins / chemistry
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • PC12 Cells
  • Phosphoric Monoester Hydrolases / chemistry
  • Phosphoric Monoester Hydrolases / genetics
  • Phosphoric Monoester Hydrolases / metabolism*
  • Presynaptic Terminals / enzymology*
  • Rats
  • Sequence Homology, Amino Acid
  • src Homology Domains


  • DNA, Complementary
  • Nerve Tissue Proteins
  • amphiphysin
  • synaptojanin
  • Phosphoric Monoester Hydrolases

Associated data

  • GENBANK/U45479