Adaptor protein complex-4 (AP-4) is expressed in the central nervous system neurons and interacts with glutamate receptor delta2.
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.
Yap
Chan Choo
CC
Laboratory for Cellular Information Processing, Brain Science Institute, RIKEN, Wako, Saitama 351-0198, Japan.
Murate
Motohide
M
Kishigami
Satoshi
S
Muto
Yuko
Y
Kishida
Haruo
H
Hashikawa
Tsutomu
T
Yano
Ryoji
R
D033964:Adaptor Protein Complex 4 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002490:Central Nervous System / Q000378:metabolism; D002522:Chlorocebus aethiops; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D017470:Receptors, Glutamate / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
D033964:Adaptor Protein Complex 4; D018076:DNA, Complementary; D017470:Receptors, Glutamate; C107913:glutamate receptor delta 2