Native and cloned 5-HT(3A)(S) receptors are anchored to F-actin in clonal cells and neurons.
Using selective antibodies to visualize the short isoform of the 5-HT(3A) receptor, we report here that both native and cloned 5-HT(3A)(S) receptors formed clusters associated with F-actin in all cell types studied. NG 108-15 cells expressing native 5-HT(3A)(S) receptors, COS-7 cells transiently expressing 5-HT(3A)(S) subunits, and CHO cells stably transfected with a plasmid encoding the 5-HT(3A)(S) sequence all exhibited similar surface receptor topology with 5-HT(3A)(S) receptor cluster accumulation in F-actin-rich lamellipodia and microspikes. Colocalization and coclustering of 5-HT(3A)(S) subunits and F-actin were also observed in transfected hippocampal neurons. Treatment of the neurons with latrunculin-A, a compound altering F-actin polymerization, demonstrated that 5-HT(3A)(S) receptor cluster size and topology were dependent on F-actin integrity. These results suggest that the anchoring of 5-HT(3A)(S) receptor clusters to the cytoskeletal network probably plays a key role in the physiological regulation of the receptor topology and dynamics, as is the case for other members of the 4-TMD ion channel receptor family.
Emerit
Michel B
MB
INSERM U288, Neuropsychopharmacologie Moléculaire, Cellulaire et Fonctionnelle, C.H.U. Pitié-Salpêtrière, 91 Bd de l'Hôpital, 75634 Paris Cedex 13, France. emerit@ext.jussieu.fr
Doucet
Edith
E
Darmon
Michèle
M
Hamon
Michel
M
D000199:Actins / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites / Q000187:drug effects / Q000502:physiology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D016466:CHO Cells; D019556:COS Cells; D002462:Cell Membrane / Q000378:metabolism*; D002490:Central Nervous System / Q000166:cytology / Q000378:metabolism*; D002999:Clone Cells / Q000166:cytology / Q000378:metabolism; D003001:Cloning, Molecular; D006224:Cricetinae; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D003599:Cytoskeleton / Q000378:metabolism*; D005333:Fetus; D005786:Gene Expression Regulation / Q000502:physiology; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D046911:Macromolecular Substances; D008968:Molecular Conformation; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011108:Polymers / Q000378:metabolism; D051381:Rats; D011985:Receptors, Serotonin / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D044406:Receptors, Serotonin, 5-HT3; D009435:Synaptic Transmission / Q000235:genetics*; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines; D014162:Transfection
D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D016895:Culture Media, Serum-Free; D046911:Macromolecular Substances; D011108:Polymers; D011985:Receptors, Serotonin; D044406:Receptors, Serotonin, 5-HT3; D013844:Thiazoles; D053778:Thiazolidines; C037067:latrunculin A