Adaptor protein complex-4 (AP-4) is expressed in the central nervous system neurons and interacts with glutamate receptor delta2

Mol Cell Neurosci. 2003 Oct;24(2):283-95. doi: 10.1016/s1044-7431(03)00164-7.


Ion channels and receptors are targeted and localized at specific postsynaptic sites to mediate neurotransmission. Receptors clustering at postsynaptic sites has been extensively studied; however, the molecular mechanisms underlying intracellular trafficking of receptors to their specific destinations remain unclear. In the present study, we found that glutamate receptor delta2 interacted directly with AP-4, a newly identified adaptor protein complex-4 that mediates protein sorting in mammalian cells. The interaction between mu4 subunit of AP-4 and the delta2 C-terminal involved multiple amino acid sequence motifs other than the classical tyrosine-based signals. AP-4 complex is expressed ubiquitously in many regions of brain, with localization on the Golgi-like structures in the cell bodies and dendrites of neurons. In addition, overexpression of mu4 substantially altered the distribution pattern of delta2 in heterologous cells. These results suggest a potential involvement of AP-4 in the trafficking of delta2 in the brain.

MeSH terms

  • Adaptor Protein Complex 4 / biosynthesis*
  • Adaptor Protein Complex 4 / genetics
  • Adaptor Protein Complex 4 / metabolism
  • Amino Acid Sequence
  • Animals
  • COS Cells
  • Central Nervous System / metabolism
  • Chlorocebus aethiops
  • DNA, Complementary / genetics
  • Gene Expression Regulation / physiology*
  • Humans
  • Molecular Sequence Data
  • Neurons / metabolism*
  • Rats
  • Rats, Wistar
  • Receptors, Glutamate / genetics
  • Receptors, Glutamate / metabolism*
  • Sequence Homology, Amino Acid


  • Adaptor Protein Complex 4
  • DNA, Complementary
  • Receptors, Glutamate
  • glutamate receptor delta 2