Rapid dendritic transport of TGN38, a putative cargo receptor.
Protein transport to and from the postsynaptic plasma membrane is thought to be of central importance for synaptic plasticity. However, the molecular details of such processes are poorly understood. One mechanism by which membrane and secretory proteins may be transported to and from postsynaptic membranes is via cargo receptors. We studied the dendritic transport of TGN38, a putative cargo receptor thought to mediate protein transport between the trans-Golgi network (TGN), endosomes, and the plasma membrane. With fluorescence time-lapse imaging of neurons expressing a TGN38-green fluorescent protein fusion protein (GFP-TGN38), we observed rapid bidirectional dynamics of the protein in dendritic shafts. In addition, the protein was present on the surface and on intracellular membranes of dendrites and dendritic spines. Finally, GFP-TGN38 was found to cycle rapidly between the plasma membrane and intracellular membranes within dendrites, including those of spines. Together, our results suggest a role for TGN38 in facilitating rapid changes in the protein composition of postsynaptic membranes.
McNamara
James O
JO
Department of Neurobiology, Duke University Medical Center, P.O. Box 3209, Durham, NC 27710, USA.
Grigston
Jeffrey C
JC
VanDongen
Hendrika M A
HM
VanDongen
Antonius M J
AM
D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D003712:Dendrites / Q000378:metabolism*; D004622:Embryo, Mammalian; D004705:Endocytosis / Q000502:physiology; D005455:Fluorescent Antibody Technique / Q000379:methods; D005786:Gene Expression Regulation / Q000502:physiology; D006624:Hippocampus / Q000166:cytology; D008164:Luminescent Proteins / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D009474:Neurons / Q000166:cytology*; D021381:Protein Transport / Q000502:physiology; D050765:Qa-SNARE Proteins; D051381:Rats; D013696:Temperature; D014162:Transfection / Q000379:methods; D021601:trans-Golgi Network / Q000378:metabolism
D001426:Bacterial Proteins; D008164:Luminescent Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D050765:Qa-SNARE Proteins; C513045:Tgoln2 protein, rat; C054562:yellow fluorescent protein, Bacteria