The role of LPA1 in formation of synapses among cultured hippocampal neurons.
We studied the lysophosphatidic acid receptor-1 (LPA1) gene, which we found to be expressed endogenously in cultured hippocampal neurons, and in vivo in young (1-week-old) rat brain slices. Overexpressed green fluorescent protein (GFP)-tagged, membrane-associated LPA1 accumulated in a punctate manner over the entire dendritic tree and caused an increase in dendritic spine density. About half of the dendritic spines in the LPA1-transfected neurons displayed distinct fluorescent puncta, and this subset of spines was also substantially larger than puncta-free, LPA1-transfected or control GFP spines. This phenotype could also be seen in cells transfected with a ligand-binding, defective mutant and is therefore not dependent on interaction with an ambient ligand. While spontaneous miniature excitatory synaptic currents were of the same amplitudes, they decayed slower in LPA1-transfected neurons compared with GFP controls. We propose that LPA1 may play a role in the formation and modulation of the dendritic spine synapse.
Pilpel
Yair
Y
Department of Neurobiology, The Weizmann Institute, Rehovot, Israel. yair.pilpel@mpimf-deidelberg.mpg.de
Segal
Menahem
M
D000818:Animals; D000831:Animals, Newborn; D001665:Binding Sites / Q000235:genetics; D002454:Cell Differentiation / Q000502:physiology*; D002478:Cells, Cultured; D049229:Dendritic Spines / Q000378:metabolism / Q000648:ultrastructure; D019706:Excitatory Postsynaptic Potentials / Q000235:genetics; D049452:Green Fluorescent Proteins; D006624:Hippocampus / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009924:Organ Culture Techniques; D011485:Protein Binding / Q000235:genetics; D051381:Rats; D049368:Receptors, Lysophosphatidic Acid / Q000235:genetics / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism*; D009435:Synaptic Transmission / Q000235:genetics; D014162:Transfection
D049368:Receptors, Lysophosphatidic Acid; D049452:Green Fluorescent Proteins