title: Endosomal localization of FIP3/Arfophilin-1 and its involvement in dendritic formation of mouse hippocampal neurons.
abstract: Endosomal trafficking mediated by Rab11 and Arf6 small GTPases is essential for various neuronal functions. Family of Rab11-interacting protein 3 (FIP3)/Arfophilin-1, also termed Eferin, is a dual effector for Rab11 and Arf6 and implicated in endosomal trafficking during cytokinesis. To understand the neuronal functions of FIP3, we first showed the widespread neuronal expression of FIP3 mRNA in adult mouse brain by in situ hybridization. Immunohistochemical analysis showed the association of FIP3 with a subpopulation of endosomes labeled with EEA1 and syntaxin 12 in hippocampal neurons. Immunoblot analysis showed the progressive increase of FIP3 with a peak around postnatal day 15 during hippocampal development. Furthermore, knockdown of endogenous FIP3 decreased the total dendritic length of cultured hippocampal neurons with a concomitant increase in the number of short (<40μm) primary dendrites. Together, FIP3 is suggested to regulate dendritic formation possibly through Rab11- and Arf6-mediated endosomal trafficking.
authors.affiliation: Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0329, Japan.
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Yazaki
authors.affiliation: Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0329, Japan.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Hara
authors.affiliation: Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0329, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Tamaki
authors.affiliation: Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0329, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Fukaya
authors.affiliation: Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0329, Japan. Electronic address: sakagami@med.kitasato-u.ac.jp.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sakagami
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D048429:Cell Size; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D003712:Dendrites / Q000502:physiology*; D011992:Endosomes / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D006367:HeLa Cells; D006624:Hippocampus / Q000166:cytology / Q000254:growth & development* / Q000502:physiology; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D008810:Mice, Inbred C57BL; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D050765:Qa-SNARE Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D033921:Vesicular Transport Proteins / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D050765:Qa-SNARE Proteins; D012333:RNA, Messenger; C000593197:Rab11-FIP3 protein, mouse; D033921:Vesicular Transport Proteins; C093846:early endosome antigen 1; C496153:syntaxin 12, mouse
keywords: ADP-ribosylation factor; Dendrite; Endosome; Membrane traffic; Rab; Small GTPase