研究者詳細 - 河野　洋治

論文 - 河野　洋治

分割表示 47 件中 41 - 47 件目／全件表示 >>

Smooth muscle contraction by small GTPase Rho 査読

Kawano Y, Yoshimura T, Kaibuchi K

Nagoya J Med Sci 65 ( 1-2 ) 1 - 8 2002年

CRMP-2 induces axons in cultured hippocampal neurons 査読

N Inagaki, K Chihara, N Arimura, C Menager, Y Kawano, N Matsuo, T Nishimura, M Amano, K Kaibuchi

NATURE NEUROSCIENCE 4 ( 8 ) 781 - 782 2001年8月

Inhibition of myosin phosphatase by upregulated Rho-kinase plays a key role for coronary artery spasm in a porcine model with interleukin-1 beta 査読

T Kandabashi, H Shimokawa, K Miyata, Kunihiro, I, Y Kawano, Y Fukata, T Higo, K Egashira, S Takahashi, K Kaibuchi, A Takeshita

CIRCULATION 101 ( 11 ) 1319 - 1323 2000年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS

Background-We recently demonstrated that the Rho-kinase-mediated pathway plays an important role for coronary artery spasm in our porcine model with interleukin-1 beta (IL-1 beta). In this study, we examined whether or not Rho-kinase is upregulated at the spastic site and if so, how it induces vascular smooth muscle hypercontraction.
Methods and Results-Segments of the left porcine coronary artery were chronically treated from the adventitia with IL-1 beta-bound microbeads. Two weeks after the operation, as reported previously, intracoronary serotonin repeatedly induced coronary hypercontractions at the IL-1 beta-treated site both in vivo and in vitro, which were. markedly inhibited by Y-27632, one of the specific inhibitors of Rho-kinase, Reverse transcription-polymerase chain reaction analysis demonstrated that the expression of Rho-kinase mRNA was significantly increased in the spastic compared with the control segment. Western blot analysis showed that during the serotonin-induced contractions, the extent of phosphorylation of the myosin-binding subunit of myosin phosphatase (MBS), one of the major substrates of Rho-kinase, was significantly greater in the spastic than in the control segment and that the increase in MBS phosphorylations was also markedly inhibited by Y-27632. There was a highly significant correlation between the extent of MBS phosphorylations and that of contractions.
Conclusions-These results indicate that Rho-kinase is upregulated at the spastic site and plays a key role in inducing vascular smooth muscle hypercontraction by inhibiting myosin phosphatase through the phosphorylation of MBS in our porcine model.

Web of Science

researchmap

Phosphorylation of myosin-binding subunit (MBS) of myosin phosphatase by Rho-kinase in vivo 査読

Y Kawano, Y Fukata, N Oshiro, M Amano, T Nakamura, M Ito, F Matsumura, M Inagaki, K Kaibuchi

JOURNAL OF CELL BIOLOGY 147 ( 5 ) 1023 - 1037 1999年11月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ROCKEFELLER UNIV PRESS

Rho-associated kinase (Rho-kinase), which is activated by the small GTPase Rho, phosphorylates myosin-binding subunit (MBS) of myosin phosphatase and thereby inactivates the phosphatase activity in vitro. Rho-kinase is thought to regulate the phosphorylation state of the substrates including myosin light chain (MLC), ERM (ezrin/radixin/moesin) family proteins and adducin by their direct phosphorylation and by the inactivation of myosin phosphatase. Here we identified the sites of phosphorylation of MBS by Rho-kinase as Thr-697, Ser-854 and several residues, and prepared antibody that specifically recognized MBS phosphorylated at Ser-854. We found by use of this antibody that the stimulation of MD CK epithelial cells with tetradecanoylphorbol-13-acetate (TPA) or hepatocyte growth factor (HGF) induced the phosphorylation of MBS at Ser-854 under the conditions in which membrane ruffling and cell migration were induced. Pretreatment of the cells with Botulinum C3 ADP-ribosyltransferase (C3),which is thought to interfere with Rho functions, or Rho-kinase inhibitors inhibited the TPA- or HGF-induced MBS phosphorylation. The TPA stimulation enhanced the immunoreactivity of phosphorylated MBS in the cytoplasm and membrane ruffling area of MDCK cells. In migrating MDCK cells, phosphorylated MBS as well as phosphorylated MLC at Ser-19 were localized in the leading edge and posterior region. Phosphorylated MBS was localized on actin stress fibers in REF52 fibroblasts. The microinjection of C3 or dominant negative Rho-kinase disrupted stress fibers and weakened the accumulation of phosphorylated MBS in REF52 cells. During cytokinesis, phosphorylated MBS, MLC and ERM family proteins accumulated at the cleavage furrow, and the phosphorylation level of MBS at Ser-854 was increased. Taken together, these results indicate that MBS is phosphorylated by Rho-kinase downstream of Rho in vivo, and suggest that myosin phosphatase and Rho-kinase spatiotemporally regulate the phosphorylation state of Rho-kinase substrates including MLC and ERM family proteins in vivo in a cooperative manner.

Web of Science

researchmap

In vivo interaction of AF-6 with activated Ras and ZO-1 査読

T Yamamoto, N Harada, Y Kawano, S Taya, K Kaibuchi

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 259 ( 1 ) 103 - 107 1999年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ACADEMIC PRESS INC

AF-6 contains two putative Ras-associating domains (RA domains) which are seen in several Ras effecters such as RalGDS and RIN1. We previously showed that an AF-6 fragment containing the amino-terminal (N-terminal) RA domain directly binds to activated Ras and ZO-1 in vitro. In this study, we showed that a single amino acid mutation in the N-terminal RA domain of AF-6 abolished the interaction of AF-6 with activated Ras and that the sites of this critical amino acid residue were similar to those for Raf-1 and RalGDS. The overexpression of the N-terminal RA domain of AF-6 inhibited the Ras-dependent c-fos promoter/enhancer stimulation in NIH3T3 cells. Endogenous AF-6 was coimmunoprecipitated with activated Ras from Rat1 cells expressing activated Ras, Moreover, we showed that AF-6 was coimmunoprecipitated with ZO-1 from Rat1 cells. Taken together, these results indicate that the Ras-interacting region on AF-6 is structurally similar to that on Raf-l and on RalGDS and that AF-6 interacts with activated Ras and ZO-1 in vivo. (C) 1999 Academic Press.

Web of Science

researchmap

Phosphorylation of adducin by rho-kinase plays a crucial role in cell motility 査読

Y Fukata, N Oshiro, N Kinoshita, Y Kawano, Y Matsuoka, Bennett, V, Y Matsuura, K Kaibuchi

JOURNAL OF CELL BIOLOGY 145 ( 2 ) 347 - 361 1999年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ROCKEFELLER UNIV PRESS

Adducin is a membrane skeletal protein that binds to actin filaments (F-actin) and thereby promotes the association of spectrin with F-actin to form a spectrin-actin meshwork beneath plasma membranes such as ruffling membranes. Rho-associated kinase (Rho-kinase), which is activated by the small guanosine triphosphatase Rho, phosphorylates alpha-adducin and thereby enhances the F-actin-binding activity of alpha-adducin in vitro. Here we identified the sites of phosphorylation of alpha-adducin by Rho-kinase as Thr445 and Thr480. We prepared antibody that specifically recognized alpha-adducin phosphorylated at Thr445, and found by use of this antibody that Rho-kinase phosphorylated alpha-adducin at Thr445 in COS7 cells in a Rho-dependent manner. Phosphorylated alpha-adducin accumulated in the membrane ruffling area of Madin-Darby canine kidney (MDCK) epithelial cells and the leading edge of scattering cells during the action of tetradecanoylphorbol-13-acetate (TPA) or hepatocyte growth factor (HGF). The microinjection of Botulinum C3 ADP-ribosyltransferase, dominant negative Rho-kinase, or alpha-adduin(T445A,T480A) (substitution of Thr445 and Thr480 by Ala) inhibited the TPA-induced membrane ruffling in MDCK cells and wound-induced migration in NRK49F cells. alpha-Adducin(T445D,T480D) (Substitution of Thr445 and Thr480 by Asp), but not alpha-adducin(T445A,T480A), counteracted the inhibitory effect of the dominant negative Rho-kinase on the TPA-induced membrane ruffling in MDCK cells. Taken together, these results indicate that Rho-kinase phosphorylates alpha-adducin downstream of Rho in vivo, and that the phosphorylation of adducin by Rho-kinase plays a crucial role in the regulation of membrane ruffling and cell motility.

Web of Science

researchmap

The Ras target AF-6 is a substrate of the Fam deubiquitinating enzyme 査読

S Taya, T Yamamoto, K Kano, Y Kawano, A Iwamatsu, T Tsuchiya, K Tanaka, M Kanai-Azuma, SA Wood, JS Mattick, K Kaibuchi

JOURNAL OF CELL BIOLOGY 142 ( 4 ) 1053 - 1062 1998年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ROCKEFELLER UNIV PRESS

The Ras target AF-6 has been shown to serve as one of the peripheral components of cell-cell adhesions, and is thought to participate in cell-cell adhesion regulation downstream of Ras. We here purified an AF-6-interacting protein with a molecular mass of similar to 220 kD (p220) to investigate the function of AF-6 at cell-cell adhesions. The peptide sequences of p220 were identical to the amino acid sequences of mouse Fam. Fam is homologous to a deubiquitinating enzyme in Drosophila, the product of the fat facets gene. Recent genetic analyses indicate that the deubiquitinating activity of the fnr facets product plays a critical role in controlling the cell fate. We found that Fam accumulated at the cell-cell contact sites of MDCKII cells, but not at free ends of plasma membranes. Fam was partially colocalized with AF-6 and interacted with AF-6 in vivo and in vitro. We also showed that AF-6 was ubiquitinated in intact cells, and that Fam prevented the ubiquitination of AF-6.
These results indicate that AF-6 forms a complex with and serves as one of the substrates for Fam, and suggest that the degradation of peripheral components of cell-cell adhesions may be regulated by Fam.

Web of Science

researchmap

　前のページ - 次のページ　

<河野 洋治>

論文 - 河野 洋治

<河野　洋治>

論文 - 河野　洋治