title: PDZ-scaffold protein, Tamalin promotes dendritic outgrowth and arborization in rat hippocampal neuron.
abstract: Tamalin is a scaffold protein known to regulate membrane trafficking through its interaction with cytohesin-2/ARNO, guanine nucleotide exchange factor (GEF) on ADP-ribosylation factor (Arf) 1/6, and induces actin reorganization. However, the neuronal function of Tamalin is not well understood. Here, we report that Tamalin participates in neurite development through the association with exchange factor for Arf6 (EFA6A)/Arf6 signaling. In immature hippocampal neuron, Tamalin knockdown markedly reduced the dendritic outgrowth, the number of dendritic tips and the levels of filamentous actin (F-actin) and microtubule-associated protein 2 (MAP2) in dendrites. In addition, Tamalin colocalized with EFA6A and Arf6 in the dendritic shaft. Tamalin knockdown reduced the number, size, and intensity of endogenous EFA6A cluster, whereas overexpression of Tamalin showed opposite effects compared with those of knockdown. These results suggest that Tamalin is responsible for neuronal dendritic development via regulation of EFA6A/Arf6-mediated cytoskeleton dynamics.
authors.affiliation: Department of Anatomy and Division of Brain Korea 21 Biomedical Science, College of Medicine, Korea University, 126-1, 5-Ka, Anam-Dong, Seongbuk-Gu, Seoul 136-705, Republic of Korea.
authors.forename: Jiwon
authors.initials: J
authors.lastname: Mo
authors.forename: Sukwoo
authors.initials: S
authors.lastname: Choi
authors.forename: Poong Gi
authors.initials: PG
authors.lastname: Ahn
authors.forename: Woong
authors.initials: W
authors.lastname: Sun
authors.forename: Hyun Woo
authors.initials: HW
authors.lastname: Lee
authors.forename: Hyun
authors.initials: H
authors.lastname: Kim
mesh_terms: D000089982:ADP-Ribosylation Factor 6; D020727:ADP-Ribosylation Factors / Q000378:metabolism; D000199:Actins / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D003712:Dendrites / Q000378:metabolism / Q000502:physiology*; D005260:Female; D055785:Gene Knockdown Techniques; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D057809:HEK293 Cells; D006624:Hippocampus / Q000166:cytology*; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D016501:Neurites / Q000378:metabolism / Q000502:physiology; D009474:Neurons / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D054731:PDZ Domains; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000089982:ADP-Ribosylation Factor 6; D000199:Actins; D002352:Carrier Proteins; C574553:GRASP protein, rat; D020662:Guanine Nucleotide Exchange Factors; D008565:Membrane Proteins; C504475:Psd protein, rat; D020727:ADP-Ribosylation Factors; C000715348:ARF6 protein, human; C000715349:Arf6 protein, rat