ノズミ　モトヒロ   野住　素広    所属   新潟薬科大学  医療技術学部 臨床検査学科    職種   教授
言語種別	英語
発行・発表の年月	2020/09/01
形態種別	論文 - 研究論文（学術雑誌）
査読	査読あり
標題	Microtubule elongation along actin filaments induced by microtubule-associated protein 4 contributes to the formation of cellular protrusions.
執筆形態	その他 - 指定なし
掲載誌名	Journal of biochemistry
掲載区分	国外
巻・号・頁	168(3),pp.295-303
著者・共著者	Chihiro Doki,Kohei Nishida,Shoma Saito,Miyuki Shiga,Hikari Ogara,Ayumu Kuramoto,Masahiro Kuragano,Motohiro Nozumi,Michihiro Igarashi,Hiroyuki Nakagawa,Susumu Kotani,Kiyotaka Tokuraku
概要	Actin-microtubule crosstalk is implicated in the formation of cellular protrusions, but the mechanism remains unclear. In this study, we examined the regulation of cell protrusion involving a ubiquitously expressed microtubule-associated protein (MAP) 4, and its superfamily proteins, neuronal MAP2 and tau. Fluorescence microscopy revealed that these MAPs bound to F-actin and microtubules simultaneously, and formed F-actin/microtubule hybrid bundles. The hybrid bundle-forming activity was in the order of MAP2 > MAP4 ≫ tau. Interestingly, the microtubule assembly-promoting activity of MAP4 and MAP2, but not of tau, was upregulated by their interaction with F-actin. When MAP4 was overexpressed in NG108-15 cells, the number of cell processes and maximum process length of each cell increased significantly by 28% and 30%, respectively. Super-resolution microscopy revealed that 95% of microtubules in cell processes colocalized with F-actin, and MAP4 was always found in their vicinity. These results suggest that microtubule elongation along F-actin induced by MAP4 contributes to the formation of cellular protrusions. Since MAP4, MAP2 and tau had different crosstalk activity between F-actin and microtubules, it is likely that the functional differentiation of these MAPs is a driving force for neural evolution, causing significant changes in cell morphology.
DOI	10.1093/jb/mvaa046
PMID	32289170