title: Distinct Functions of Endophilin Isoforms in Synaptic Vesicle Endocytosis.
abstract: Endophilin isoforms perform distinct characteristics in their interactions with N-type Ca(2+) channels and dynamin. However, precise functional differences for the endophilin isoforms on synaptic vesicle (SV) endocytosis remain unknown. By coupling RNA interference and electrophysiological recording techniques in cultured rat hippocampal neurons, we investigated the functional differences of three isoforms of endophilin in SV endocytosis. The results showed that the amplitude of normalized evoked excitatory postsynaptic currents in endophilin1 knockdown neurons decreased significantly for both single train and multiple train stimulations. Similar results were found using endophilin2 knockdown neurons, whereas endophilin3 siRNA exhibited no change compared with control neurons. Endophilin1 and endophilin2 affected SV endocytosis, but the effect of endophilin1 and endophilin2 double knockdown was not different from that of either knockdown alone. This result suggested that endophilin1 and endophilin2 functioned together but not independently during SV endocytosis. Taken together, our results indicate that SV endocytosis is sustained by endophilin1 and endophilin2 isoforms, but not by endophilin3, in primary cultured hippocampal neurons.
authors.affiliation: Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China ; Center for Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China.
authors.forename: Jifeng
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China ; Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
authors.forename: Minghui
authors.initials: M
authors.lastname: Tan
authors.affiliation: Department of Neurology, Guangzhou Red Cross Hospital, The Fourth Affiliated Hospital of Jinan University, Guangzhou 510220, China.
authors.forename: Yichen
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Center for Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China.
authors.forename: Bingyu
authors.initials: B
authors.lastname: Ren
authors.affiliation: Center for Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China.
authors.forename: Nannan
authors.initials: N
authors.lastname: Jiang
authors.affiliation: Department of Anatomy, Medical College of Jinan University, Guangzhou 510630, China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Guo
authors.affiliation: Center for Neurobiology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000217:Acyltransferases / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D002478:Cells, Cultured; D004705:Endocytosis; D019706:Excitatory Postsynaptic Potentials; D057809:HEK293 Cells; D006624:Hippocampus / Q000201:enzymology / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D009419:Nerve Tissue Proteins / Q000378:metabolism / Q000502:physiology*; D009474:Neurons / Q000201:enzymology / Q000378:metabolism / Q000502:physiology*; D020033:Protein Isoforms / Q000378:metabolism / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013572:Synaptic Vesicles / Q000502:physiology*
chemical_list: D009419:Nerve Tissue Proteins; D020033:Protein Isoforms; C519036:endophilin 3, rat; D000217:Acyltransferases; C018764:2-acylglycerophosphate acyltransferase