Interaction of the N-terminal domain of the AMPA receptor GluR4 subunit with the neuronal pentraxin NP1 mediates GluR4 synaptic recruitment.
Synaptogenesis requires recruitment of neurotransmitter receptors to developing postsynaptic specializations. We developed a coculture system reconstituting artificial synapses between neurons and nonneuronal cells to investigate the molecular components required for AMPA-receptor recruitment to synapses. With this system, we find that excitatory axons specifically express factors that recruit the AMPA receptor GluR4 subunit to sites of contact between axons and GluR4-transfected nonneuronal cells. Furthermore, the N-terminal domain (NTD) of GluR4 is necessary and sufficient for its recruitment to these artificial synapses and also for GluR4 recruitment to native synapses. Moreover, we show that axonally derived neuronal pentraxins NP1 and NPR are required for GluR4 recruitment to artificial and native synapses. RNAi knockdown and knockout of the neuronal pentraxins significantly decreases GluR4 targeting to synapses. Our results indicate that NP1 and NPR secreted from presynaptic neurons bind to the GluR4 NTD and are critical trans-synaptic factors for GluR4 recruitment to synapses.
Sia
Gek-Ming
GM
Department of Neuroscience and Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA.
Béïque
Jean-Claude
JC
Rumbaugh
Gavin
G
Cho
Richard
R
Worley
Paul F
PF
Huganir
Richard L
RL
D000818:Animals; D001369:Axons / Q000502:physiology; D002097:C-Reactive Protein / Q000235:genetics / Q000502:physiology*; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000235:genetics; D004594:Electrophysiology; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000502:physiology; D006624:Hippocampus / Q000166:cytology / Q000502:physiology; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D051379:Mice; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology*; D009457:Neuroglia / Q000378:metabolism; D009474:Neurons / Q000502:physiology*; D018408:Patch-Clamp Techniques; D034741:RNA, Small Interfering / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000502:physiology*; D011999:Recruitment, Neurophysiological / Q000502:physiology*; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology; D014162:Transfection; D000099153:Pentraxins
D002097:C-Reactive Protein; D004247:DNA; D049452:Green Fluorescent Proteins; D009419:Nerve Tissue Proteins; D034741:RNA, Small Interfering; D018091:Receptors, AMPA; D000099153:Pentraxins; C104724:glutamate receptor ionotropic, AMPA 4