The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Masaki Inagaki - One of the best experts on this subject based on the ideXlab platform.
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aurora b and rho kinase rock the two Cleavage Furrow kinases independently regulate the progression of cytokinesis possible existence of a novel Cleavage Furrow kinase phosphorylates ezrin radixin moesin erm
Genes to Cells, 2005Co-Authors: Tomoya Yokoyama, Hidemasa Goto, Ichiro Izawa, Hitoshi Mizutani, Masaki InagakiAbstract:Cytokinesis is regulated by several protein kinases, such as Aurora-B and Rho-kinase/ROCK. We have indicated that these two kinases are the Cleavage Furrow (CF) kinases that accumulate at the Cleavage Furrow and phosphorylate several intermediate filament (IF) proteins into two daughter cells. It has been reported that Aurora-B phosphorylates MgcRacGAP to functionally convert to a RhoGAP during cytokinesis. Therefore, we investigated here the relationship between Aurora-B and Rho-kinase/ROCK in cytokinesis, by using small interfering RNA (siRNA) technique. Aurora-B depletion did not alter the Cleavage Furrow-specific localization of Rho-kinase/ROCK and vice versa. Treatment of Aurora-B or Rho-kinase/ROCK siRNA increased multinucleate cells, and the effect of double depletion was additive. Aurora-B depletion induced the reduction of Cleavage Furrow-specific phosphorylation of vimentin at Ser72 but not vimentin at Ser71, myosin light chain (MLC) at Ser19, and myosin binding subunit of myosin phosphatase (MBS) at Ser852. In contrast, Rho-kinase/ROCK depletion led to the reduction of Cleavage Furrow-specific phosphorylation of MLC at Ser19, MBS at Ser852, and vimentin at Ser71 but not vimentin at Ser72. Cleavage Furrow-specific ezrin/radixin/moesin (ERM) phosphorylation was not altered in the Aurora-B- and/or Rho-kinase/ROCK-depleted cells. In addition, C3 or toxin B treatment did not abolish ERM phosphorylation at the Cleavage Furrow in cells attaining cytokinesis. These results suggest that Aurora-B and Rho-kinase/ROCK regulate the progression of cytokinesis without communicating to each other, and there may exist a novel protein kinase which phosphorylates ERM at the Cleavage Furrow.
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Aurora-B and Rho-kinase/ROCK, the two Cleavage Furrow kinases, independently regulate the progression of cytokinesis: possible existence of a novel Cleavage Furrow kinase phosphorylates ezrin/radixin/moesin (ERM).
Genes to cells : devoted to molecular & cellular mechanisms, 2005Co-Authors: Tomoya Yokoyama, Hidemasa Goto, Ichiro Izawa, Hitoshi Mizutani, Masaki InagakiAbstract:Cytokinesis is regulated by several protein kinases, such as Aurora-B and Rho-kinase/ROCK. We have indicated that these two kinases are the Cleavage Furrow (CF) kinases that accumulate at the Cleavage Furrow and phosphorylate several intermediate filament (IF) proteins into two daughter cells. It has been reported that Aurora-B phosphorylates MgcRacGAP to functionally convert to a RhoGAP during cytokinesis. Therefore, we investigated here the relationship between Aurora-B and Rho-kinase/ROCK in cytokinesis, by using small interfering RNA (siRNA) technique. Aurora-B depletion did not alter the Cleavage Furrow-specific localization of Rho-kinase/ROCK and vice versa. Treatment of Aurora-B or Rho-kinase/ROCK siRNA increased multinucleate cells, and the effect of double depletion was additive. Aurora-B depletion induced the reduction of Cleavage Furrow-specific phosphorylation of vimentin at Ser72 but not vimentin at Ser71, myosin light chain (MLC) at Ser19, and myosin binding subunit of myosin phosphatase (MBS) at Ser852. In contrast, Rho-kinase/ROCK depletion led to the reduction of Cleavage Furrow-specific phosphorylation of MLC at Ser19, MBS at Ser852, and vimentin at Ser71 but not vimentin at Ser72. Cleavage Furrow-specific ezrin/radixin/moesin (ERM) phosphorylation was not altered in the Aurora-B- and/or Rho-kinase/ROCK-depleted cells. In addition, C3 or toxin B treatment did not abolish ERM phosphorylation at the Cleavage Furrow in cells attaining cytokinesis. These results suggest that Aurora-B and Rho-kinase/ROCK regulate the progression of cytokinesis without communicating to each other, and there may exist a novel protein kinase which phosphorylates ERM at the Cleavage Furrow.
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functional significance of the specific sites phosphorylated in desmin at Cleavage Furrow aurora b may phosphorylate and regulate type iii intermediate filaments during cytokinesis coordinatedly with rho kinase
Molecular Biology of the Cell, 2003Co-Authors: Aie Kawajiri, Hidemasa Goto, Yoshihiro Yasui, Koh-ichi Nagata, Masaaki Tatsuka, Masahide Takahashi, Masaki InagakiAbstract:Aurora-B is a protein kinase required for chromosome segregation and the progression of cytokinesis during the cell cycle. We report here that Aurora-B phosphorylates GFAP and desmin in vitro, and this phosphorylation leads to a reduction in filament forming ability. The sites phosphorylated by Aurora-B; Thr-7/Ser-13/Ser-38 of GFAP, and Thr-16 of desmin are common with those related to Rho-associated kinase (Rho-kinase), which has been reported to phosphorylate GFAP and desmin at Cleavage Furrow during cytokinesis. We identified Ser-59 of desmin to be a specific site phosphorylated by Aurora-B in vitro. Use of an antibody that specifically recognized desmin phosphorylated at Ser-59 led to the finding that the site is also phosphorylated specifically at the Cleavage Furrow during cytokinesis in Saos-2 cells. Desmin mutants, in which in vitro phosphorylation sites by Aurora-B and/or Rho-kinase are changed to Ala or Gly, cause dramatic defects in filament separation between daughter cells in cytokinesis. The results presented here suggest the possibility that Aurora-B may regulate Cleavage Furrow-specific phosphorylation and segregation of type III IFs coordinatedly with Rho-kinase during cytokinesis.
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aurora b regulates the Cleavage Furrow specific vimentin phosphorylation in the cytokinetic process
Journal of Biological Chemistry, 2003Co-Authors: Hidemasa Goto, Erich A. Nigg, Yoshihiro Yasui, Koh-ichi Nagata, Aie Kawajiri, Yasuhiko Terada, Masaaki Tatsuka, Masaki InagakiAbstract:Aurora-B is an evolutionally conserved protein kinase that regulates several mitotic events including cytokinesis. We previously demonstrated the possible existence of a protein kinase that phosphorylates at least Ser-72 on vimentin, the most widely expressed intermediate filament protein, in the Cleavage Furrow-specific manner. Here we showed that vimentin-Ser-72 phosphorylation occurred specifically at the border of the Aurora-B-localized area from anaphase to telophase. Expression of a dominant-negative mutant of Aurora-B led to a reduction of this vimentin-Ser-72 phosphorylation. In vitro analyses revealed that Aurora-B phosphorylates vimentin at approximately 2 mol phosphate/mol of substrate for 30 min and that this phosphorylation dramatically inhibits vimentin filament formation. We further identified eight Aurora-B phosphorylation sites, including Ser-72 on vimentin, and then constructed the mutant vimentin in which these identified sites are changed into Ala. Cells expressing this mutant formed an unusually long bridge-like intermediate filament structure between unseparated daughter cells. We then identified important phosphorylation sites for the bridge phenotype. Our findings indicate that Aurora-B regulates the Cleavage Furrow-specific vimentin phosphorylation and controls vimentin filament segregation in cytokinetic process.
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aurora b regulates the Cleavage Furrow specific vimentin phosphorylation in the cytokinetic process
Journal of Biological Chemistry, 2003Co-Authors: Hidemasa Goto, Erich A. Nigg, Yoshihiro Yasui, Koh-ichi Nagata, Aie Kawajiri, Yasuhiko Terada, Masaaki Tatsuka, Masaki InagakiAbstract:Aurora-B is an evolutionally conserved protein kinase that regulates several mitotic events including cytokinesis. We previously demonstrated the possible existence of a protein kinase that phosphorylates at least Ser-72 on vimentin, the most widely expressed intermediate filament protein, in the Cleavage Furrow-specific manner. Here we showed that vimentin-Ser-72 phosphorylation occurred specifically at the border of the Aurora-B-localized area from anaphase to telophase. Expression of a dominant-negative mutant of Aurora-B led to a reduction of this vimentin-Ser-72 phosphorylation. In vitro analyses revealed that Aurora-B phosphorylates vimentin at ∼2 mol phosphate/mol of substrate for 30 min and that this phosphorylation dramatically inhibits vimentin filament formation. We further identified eight Aurora-B phosphorylation sites, including Ser-72 on vimentin, and then constructed the mutant vimentin in which these identified sites are changed into Ala. Cells expressing this mutant formed an unusually long bridge-like intermediate filament structure between unseparated daughter cells. We then identified important phosphorylation sites for the bridge phenotype. Our findings indicate that Aurora-B regulates the Cleavage Furrow-specific vimentin phosphorylation and controls vimentin filament segregation in cytokinetic process.
Hidemasa Goto - One of the best experts on this subject based on the ideXlab platform.
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aurora b and rho kinase rock the two Cleavage Furrow kinases independently regulate the progression of cytokinesis possible existence of a novel Cleavage Furrow kinase phosphorylates ezrin radixin moesin erm
Genes to Cells, 2005Co-Authors: Tomoya Yokoyama, Hidemasa Goto, Ichiro Izawa, Hitoshi Mizutani, Masaki InagakiAbstract:Cytokinesis is regulated by several protein kinases, such as Aurora-B and Rho-kinase/ROCK. We have indicated that these two kinases are the Cleavage Furrow (CF) kinases that accumulate at the Cleavage Furrow and phosphorylate several intermediate filament (IF) proteins into two daughter cells. It has been reported that Aurora-B phosphorylates MgcRacGAP to functionally convert to a RhoGAP during cytokinesis. Therefore, we investigated here the relationship between Aurora-B and Rho-kinase/ROCK in cytokinesis, by using small interfering RNA (siRNA) technique. Aurora-B depletion did not alter the Cleavage Furrow-specific localization of Rho-kinase/ROCK and vice versa. Treatment of Aurora-B or Rho-kinase/ROCK siRNA increased multinucleate cells, and the effect of double depletion was additive. Aurora-B depletion induced the reduction of Cleavage Furrow-specific phosphorylation of vimentin at Ser72 but not vimentin at Ser71, myosin light chain (MLC) at Ser19, and myosin binding subunit of myosin phosphatase (MBS) at Ser852. In contrast, Rho-kinase/ROCK depletion led to the reduction of Cleavage Furrow-specific phosphorylation of MLC at Ser19, MBS at Ser852, and vimentin at Ser71 but not vimentin at Ser72. Cleavage Furrow-specific ezrin/radixin/moesin (ERM) phosphorylation was not altered in the Aurora-B- and/or Rho-kinase/ROCK-depleted cells. In addition, C3 or toxin B treatment did not abolish ERM phosphorylation at the Cleavage Furrow in cells attaining cytokinesis. These results suggest that Aurora-B and Rho-kinase/ROCK regulate the progression of cytokinesis without communicating to each other, and there may exist a novel protein kinase which phosphorylates ERM at the Cleavage Furrow.
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Aurora-B and Rho-kinase/ROCK, the two Cleavage Furrow kinases, independently regulate the progression of cytokinesis: possible existence of a novel Cleavage Furrow kinase phosphorylates ezrin/radixin/moesin (ERM).
Genes to cells : devoted to molecular & cellular mechanisms, 2005Co-Authors: Tomoya Yokoyama, Hidemasa Goto, Ichiro Izawa, Hitoshi Mizutani, Masaki InagakiAbstract:Cytokinesis is regulated by several protein kinases, such as Aurora-B and Rho-kinase/ROCK. We have indicated that these two kinases are the Cleavage Furrow (CF) kinases that accumulate at the Cleavage Furrow and phosphorylate several intermediate filament (IF) proteins into two daughter cells. It has been reported that Aurora-B phosphorylates MgcRacGAP to functionally convert to a RhoGAP during cytokinesis. Therefore, we investigated here the relationship between Aurora-B and Rho-kinase/ROCK in cytokinesis, by using small interfering RNA (siRNA) technique. Aurora-B depletion did not alter the Cleavage Furrow-specific localization of Rho-kinase/ROCK and vice versa. Treatment of Aurora-B or Rho-kinase/ROCK siRNA increased multinucleate cells, and the effect of double depletion was additive. Aurora-B depletion induced the reduction of Cleavage Furrow-specific phosphorylation of vimentin at Ser72 but not vimentin at Ser71, myosin light chain (MLC) at Ser19, and myosin binding subunit of myosin phosphatase (MBS) at Ser852. In contrast, Rho-kinase/ROCK depletion led to the reduction of Cleavage Furrow-specific phosphorylation of MLC at Ser19, MBS at Ser852, and vimentin at Ser71 but not vimentin at Ser72. Cleavage Furrow-specific ezrin/radixin/moesin (ERM) phosphorylation was not altered in the Aurora-B- and/or Rho-kinase/ROCK-depleted cells. In addition, C3 or toxin B treatment did not abolish ERM phosphorylation at the Cleavage Furrow in cells attaining cytokinesis. These results suggest that Aurora-B and Rho-kinase/ROCK regulate the progression of cytokinesis without communicating to each other, and there may exist a novel protein kinase which phosphorylates ERM at the Cleavage Furrow.
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functional significance of the specific sites phosphorylated in desmin at Cleavage Furrow aurora b may phosphorylate and regulate type iii intermediate filaments during cytokinesis coordinatedly with rho kinase
Molecular Biology of the Cell, 2003Co-Authors: Aie Kawajiri, Hidemasa Goto, Yoshihiro Yasui, Koh-ichi Nagata, Masaaki Tatsuka, Masahide Takahashi, Masaki InagakiAbstract:Aurora-B is a protein kinase required for chromosome segregation and the progression of cytokinesis during the cell cycle. We report here that Aurora-B phosphorylates GFAP and desmin in vitro, and this phosphorylation leads to a reduction in filament forming ability. The sites phosphorylated by Aurora-B; Thr-7/Ser-13/Ser-38 of GFAP, and Thr-16 of desmin are common with those related to Rho-associated kinase (Rho-kinase), which has been reported to phosphorylate GFAP and desmin at Cleavage Furrow during cytokinesis. We identified Ser-59 of desmin to be a specific site phosphorylated by Aurora-B in vitro. Use of an antibody that specifically recognized desmin phosphorylated at Ser-59 led to the finding that the site is also phosphorylated specifically at the Cleavage Furrow during cytokinesis in Saos-2 cells. Desmin mutants, in which in vitro phosphorylation sites by Aurora-B and/or Rho-kinase are changed to Ala or Gly, cause dramatic defects in filament separation between daughter cells in cytokinesis. The results presented here suggest the possibility that Aurora-B may regulate Cleavage Furrow-specific phosphorylation and segregation of type III IFs coordinatedly with Rho-kinase during cytokinesis.
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aurora b regulates the Cleavage Furrow specific vimentin phosphorylation in the cytokinetic process
Journal of Biological Chemistry, 2003Co-Authors: Hidemasa Goto, Erich A. Nigg, Yoshihiro Yasui, Koh-ichi Nagata, Aie Kawajiri, Yasuhiko Terada, Masaaki Tatsuka, Masaki InagakiAbstract:Aurora-B is an evolutionally conserved protein kinase that regulates several mitotic events including cytokinesis. We previously demonstrated the possible existence of a protein kinase that phosphorylates at least Ser-72 on vimentin, the most widely expressed intermediate filament protein, in the Cleavage Furrow-specific manner. Here we showed that vimentin-Ser-72 phosphorylation occurred specifically at the border of the Aurora-B-localized area from anaphase to telophase. Expression of a dominant-negative mutant of Aurora-B led to a reduction of this vimentin-Ser-72 phosphorylation. In vitro analyses revealed that Aurora-B phosphorylates vimentin at approximately 2 mol phosphate/mol of substrate for 30 min and that this phosphorylation dramatically inhibits vimentin filament formation. We further identified eight Aurora-B phosphorylation sites, including Ser-72 on vimentin, and then constructed the mutant vimentin in which these identified sites are changed into Ala. Cells expressing this mutant formed an unusually long bridge-like intermediate filament structure between unseparated daughter cells. We then identified important phosphorylation sites for the bridge phenotype. Our findings indicate that Aurora-B regulates the Cleavage Furrow-specific vimentin phosphorylation and controls vimentin filament segregation in cytokinetic process.
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aurora b regulates the Cleavage Furrow specific vimentin phosphorylation in the cytokinetic process
Journal of Biological Chemistry, 2003Co-Authors: Hidemasa Goto, Erich A. Nigg, Yoshihiro Yasui, Koh-ichi Nagata, Aie Kawajiri, Yasuhiko Terada, Masaaki Tatsuka, Masaki InagakiAbstract:Aurora-B is an evolutionally conserved protein kinase that regulates several mitotic events including cytokinesis. We previously demonstrated the possible existence of a protein kinase that phosphorylates at least Ser-72 on vimentin, the most widely expressed intermediate filament protein, in the Cleavage Furrow-specific manner. Here we showed that vimentin-Ser-72 phosphorylation occurred specifically at the border of the Aurora-B-localized area from anaphase to telophase. Expression of a dominant-negative mutant of Aurora-B led to a reduction of this vimentin-Ser-72 phosphorylation. In vitro analyses revealed that Aurora-B phosphorylates vimentin at ∼2 mol phosphate/mol of substrate for 30 min and that this phosphorylation dramatically inhibits vimentin filament formation. We further identified eight Aurora-B phosphorylation sites, including Ser-72 on vimentin, and then constructed the mutant vimentin in which these identified sites are changed into Ala. Cells expressing this mutant formed an unusually long bridge-like intermediate filament structure between unseparated daughter cells. We then identified important phosphorylation sites for the bridge phenotype. Our findings indicate that Aurora-B regulates the Cleavage Furrow-specific vimentin phosphorylation and controls vimentin filament segregation in cytokinetic process.
Hidetaka Kosako - One of the best experts on this subject based on the ideXlab platform.
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Rho-kinase/ROCK is involved in cytokinesis through the phosphorylation of myosin light chain and not ezrin/radixin/moesin proteins at the Cleavage Furrow.
Oncogene, 2000Co-Authors: Hidetaka Kosako, Toshimasa Ishizaki, Shuh Narumiya, Toshimichi Yoshida, Fumio Matsumura, Masaki InagakiAbstract:The small GTPase Rho and one of its targets, Rho-kinase (also termed ROK or ROCK), are implicated in various cellular functions including stress fiber formation, smooth muscle contraction, tumor cell invasion and cell motility. We have previously reported that Rho-kinase accumulates at the Cleavage Furrow during cytokinesis in several cultured cells. Here, using Rho-kinase inhibitors, Y-27632 and HA1077, we found that Rho-kinase is responsible for the phosphorylation of myosin regulatory light chain at Ser19 in the Cleavage Furrow during cytokinesis. On the other hand, phosphorylation of ezrin/radixin/moesin (ERM) proteins at the Cleavage Furrow was enhanced by the addition of the above Rho-kinase inhibitors. Treatment with Y-27632 strongly enhanced the accumulation of Rho-kinase but not RhoA and citron kinase at the Cleavage Furrow. Furthermore, the Furrow ingression in cytokinesis was significantly prolonged in the presence of Y-27632. These results suggest that Rho-kinase is involved in the progression of cytokinesis through the phosphorylation of several proteins including myosin light chain at the Cleavage Furrow.
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rho kinase rock is involved in cytokinesis through the phosphorylation of myosin light chain and not ezrin radixin moesin proteins at the Cleavage Furrow
Oncogene, 2000Co-Authors: Hidetaka Kosako, Toshimasa Ishizaki, Shuh Narumiya, Toshimichi Yoshida, Fumio Matsumura, Masaki InagakiAbstract:The small GTPase Rho and one of its targets, Rho-kinase (also termed ROK or ROCK), are implicated in various cellular functions including stress fiber formation, smooth muscle contraction, tumor cell invasion and cell motility. We have previously reported that Rho-kinase accumulates at the Cleavage Furrow during cytokinesis in several cultured cells. Here, using Rho-kinase inhibitors, Y-27632 and HA1077, we found that Rho-kinase is responsible for the phosphorylation of myosin regulatory light chain at Ser19 in the Cleavage Furrow during cytokinesis. On the other hand, phosphorylation of ezrin/radixin/moesin (ERM) proteins at the Cleavage Furrow was enhanced by the addition of the above Rho-kinase inhibitors. Treatment with Y-27632 strongly enhanced the accumulation of Rho-kinase but not RhoA and citron kinase at the Cleavage Furrow. Furthermore, the Furrow ingression in cytokinesis was significantly prolonged in the presence of Y-27632. These results suggest that Rho-kinase is involved in the progression of cytokinesis through the phosphorylation of several proteins including myosin light chain at the Cleavage Furrow.
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Specific accumulation of Rho-associated kinase at the Cleavage Furrow during cytokinesis: Cleavage Furrow-specific phosphorylation of intermediate filaments
Oncogene, 1999Co-Authors: Hidetaka Kosako, Hidemasa Goto, Maki Yanagida, Kaori Matsuzawa, Masatoshi Fujita, Yasuko Tomono, Tohru Okigaki, Hideharu Odai, Kozo Kaibuchi, Masaki InagakiAbstract:The small GTPase Rho and one of its targets, Rho-associated kinase (Rho-kinase), are implicated in a wide spectrum of cellular functions, including cytoskeletal rearrangements, transcriptional activation and smooth muscle contraction. Since Rho also plays an essential role in cytokinesis, Rho-kinase may possibly mediate some biological aspects of cytokinesis. Here, using a series of monoclonal antibodies that can specifically recognize distinct phosphorylated sites on glial fibrillary acidic protein (GFAP) and vimentin, phosphorylation sites by Rho-kinase in vitro were revealed to be identical to in vivo phosphorylation sites on these intermediate filament (IF) proteins at the Cleavage Furrow in dividing cells. We then found, by preparing two types of anti-Rho-kinase antibodies, that Rho-kinase accumulated highly and circumferentially at the Cleavage Furrow in various cell lines. This subcellular distribution during cytokinesis was very similar to that of ezrin/radixin/moesin (ERM) proteins and Ser19-phosphorylated myosin light chain. These results raise the possibility that Rho-kinase might be involved in the formation of the contractile ring by modulating these F-actin-binding proteins during cytokinesis and in the phosphorylation and regulation of IF proteins at the Cleavage Furrow.
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Phosphorylation of Glial Fibrillary Acidic Protein at the Same Sites by Cleavage Furrow Kinase and Rho-associated Kinase *
The Journal of biological chemistry, 1997Co-Authors: Hidetaka Kosako, Maki Yanagida, Kozo Kaibuchi, Mutsuki Amano, Kazushi Tanabe, Yoshimi Nishi, Masaki InagakiAbstract:Site- and phosphorylation state-specific antibodies are useful to analyze spatiotemporal distribution of site-specific phosphorylation of target proteins in vivo. Using several polyclonal and monoclonal antibodies that can specifically recognize four phosphorylated sites on glial fibrillary acidic protein (GFAP), we have previously reported that Thr-7, Ser-13, and Ser-34 on this intermediate filament protein are phosphorylated at the Cleavage Furrow during cytokinesis. This observation suggests that there exists a protein kinase named Cleavage Furrow kinase specifically activated at metaphase-anaphase transition (Matsuoka, Y., Nishizawa, K., Yano, T., Shibata, M., Ando, S., Takahashi, T., and Inagaki, M. (1992) EMBO J. 11, 2895-2902; Sekimata, M., Tsujimura, K., Tanaka, J., Takeuchi, Y., Inagaki, N., and Inagaki, M. (1996) J. Cell Biol. 132, 635-641). Here we report that GFAP is phosphorylated specifically at Thr-7, Ser-13, and Ser-34 by Rho-associated kinase (Rho-kinase), which binds to the small GTPase Rho in its GTP-bound active form. The kinase activity of Rho-kinase toward GFAP is dramatically stimulated by guanosine 5'-(3-O-thio)-triphosphate-bound RhoA. Furthermore, the phosphorylation of GFAP by Rho-kinase results in a nearly complete inhibition of its filament formation in vitro. The possibility that Rho-kinase is a candidate for Cleavage Furrow kinase is discussed.
Chris Q. Doe - One of the best experts on this subject based on the ideXlab platform.
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Asymmetric cortical extension shifts Cleavage Furrow position in Drosophila neuroblasts.
Molecular biology of the cell, 2011Co-Authors: Marisa Connell, Clemens Cabernard, Chris Q. Doe, Derek Ricketson, Kenneth E. PrehodaAbstract:The cytokinetic Cleavage Furrow is typically positioned symmetrically relative to the cortical cell boundaries, but it can also be asymmetric. The mechanisms that control Furrow site specification have been intensively studied, but how polar cortex movements influence ultimate Furrow position remains poorly understood. We measured the position of the apical and the basal cortex in asymmetrically dividing Drosophila neuroblasts and observed preferential displacement of the apical cortex that becomes the larger daughter cell during anaphase, effectively shifting the Cleavage Furrow toward the smaller daughter cell. Asymmetric cortical extension is correlated with the presence of cortical myosin II, which is polarized in neuroblasts. Loss of myosin II asymmetry by perturbing heterotrimeric G-protein signaling results in symmetric extension and equal-sized daughter cells. We propose a model in which contraction-driven asymmetric polar extension of the neuroblast cortex during anaphase contributes to asymmetric Furrow position and daughter cell size.
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A spindle-independent Cleavage Furrow positioning pathway
Nature, 2010Co-Authors: Clemens Cabernard, Kenneth E. Prehoda, Chris Q. DoeAbstract:The mitotic spindle determines the Cleavage Furrow site during metazoan cell division, but whether other mechanisms exist remains unknown. Here we identify a spindle-independent mechanism for Cleavage Furrow positioning in Drosophila neuroblasts. We show that early and late Furrow proteins (Pavarotti, Anillin, and Myosin) are localized to the neuroblast basal cortex at anaphase onset by a Pins cortical polarity pathway, and can induce a basally displaced Furrow even in the complete absence of a mitotic spindle. Rotation or displacement of the spindle results in two Furrows: an early polarity-induced basal Furrow and a later spindle-induced Furrow. This spindle-independent Cleavage Furrow mechanism may be relevant to other highly polarized mitotic cells, such as mammalian neural progenitors.
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A spindle-independent Cleavage Furrow positioning pathway
Nature, 2010Co-Authors: Clemens Cabernard, Kenneth E. Prehoda, Chris Q. DoeAbstract:In the textbook model of metazoan cell division — based on a century of work on relatively large marine cells and Caenorhabditis elegans — the mitotic spindle is assumed to direct the position of the Cleavage Furrow. Now experiments to test whether this model is sufficient to explain Furrow position during asymmetric cell division of a smaller cell — the Drosophila neuroblast — suggest that it cannot. Instead, a novel pathway operates in which the Pins (Partner of Inscuteable) polarity complex polarizes Furrow-forming proteins to the basal cortex where they induce contractile ring formation. This spindle-independent cytokinetic Furrow mechanism may be relevant to other highly polarized cell types. The mitotic spindle determines the Cleavage Furrow site during metazoan cell division^ 1 , 2 , but whether other mechanisms exist remains unknown. Here we identify a spindle-independent mechanism for Cleavage Furrow positioning in Drosophila neuroblasts. We show that early and late Furrow proteins (Pavarotti, Anillin, and Myosin) are localized to the neuroblast basal cortex at anaphase onset by a Pins cortical polarity pathway, and can induce a basally displaced Furrow even in the complete absence of a mitotic spindle. Rotation or displacement of the spindle results in two Furrows: an early polarity-induced basal Furrow and a later spindle-induced Furrow. This spindle-independent Cleavage Furrow mechanism may be relevant to other highly polarized mitotic cells, such as mammalian neural progenitors. The mitotic spindle plays a key part in determining the site of the Cleavage Furrow in dividing metazoan cells. But are other mechanisms also involved? Here evidence is provided for a spindle-independent pathway for Furrow positioning that occurs during asymmetric divisions of Drosophila neuroblast cells. The pathway involves the Pins protein complex, which polarizes Furrow-forming proteins to the basal cortex of the cell. This mechanism might also occur in other highly polarized cell types.
Shuh Narumiya - One of the best experts on this subject based on the ideXlab platform.
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Local change in phospholipid composition at the Cleavage Furrow is essential for completion of cytokinesis
The Journal of biological chemistry, 2005Co-Authors: Kazuo Emoto, Shuh Narumiya, Hironori Inadome, Yasunori Kanaho, Masato UmedaAbstract:Cell division ends up with the membrane separation of two daughter cells, presumably by a membrane fusion that requires dynamic changes of the distribution and the composition of membrane lipids. We have previously shown that a membrane lipid phosphatidylethanolamine (PE) is exposed on the cell surface of the Cleavage Furrow during late cytokinesis and that this PE movement is involved in regulation of the contractile ring disassembly. Here we show that immobilization of cell surface PE by a PE-binding peptide blocks the RhoA inactivation in the late stage of cytokinesis. Phosphatidylinositol 4-phosphate 5-kinase (PIP5K), but not other RhoA effectors, is co-localized with RhoA in the peptide-treated cells. Indeed, PIP5K and its product phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) are localized to the Cleavage Furrow of normally dividing cells. Both overexpression of a kinase-deficient PIP5K mutant and microinjection of anti-PI(4,5)P2 antibodies compromise cytokinesis by preventing local accumulation of PI(4,5)P2 in the Cleavage Furrow. These findings demonstrate that the localized production of PI(4,5)P2 is required for the proper completion of cytokinesis and that the possible formation of a unique lipid domain in the Cleavage Furrow membrane may play a crucial role in coordinating the contractile rearrangement with the membrane remodeling during late cytokinesis.
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Rho-dependent transfer of Citron-kinase to the Cleavage Furrow of dividing cells.
Journal of Cell Science, 2001Co-Authors: Masatoshi Eda, Shigenobu Yonemura, Takayuki Kato, Naoki Watanabe, Toshimasa Ishizaki, Pascal Madaule, Shuh NarumiyaAbstract:Citron-kinase (Citron-K) is a Rho effector working in cytokinesis. It is enriched in Cleavage Furrow, but how Rho mobilizes Citron-K remains unknown. Using anti-Citron antibody and a Citron-K Green Fluorescence Protein (GFP)-fusion, we monitored its localization in cell cycle. We have found: (1) Citron-K is present as aggregates in interphase cells, disperses throughout the cytoplasm in prometaphase, translocates to cell cortex in anaphase and accumulates in Cleavage Furrow in telophase; (2) Rho colocalizes with Citron-K in the cortex of ana- to telophase cells and the two proteins are concentrated in the Cleavage Furrow and to the midbody; (3) inactivation of Rho by C3 exoenzyme does not affect the dispersion of Citron-K in prometaphase, but prevented its transfer to the cell cortex, and Citron-K stays in association with the midzone spindles of C3 exoenzyme-treated cells. To clarify further the mechanism of the Rho-mediated transfer and concentration of Citron-K in Cleavage Furrow, we expressed active Val14RhoA in interphase cells expressing GFP-Citron-K. Val14RhoA expression transferred Citron-K to the ventral cortex of interphase cells, where it formed band-like structures in a complex with Rho. This structure was localized at the same plane as actin stress fibers, and they exclude each other. Disruption of F-actin abolished the band and dispersed the Citron-K-Rho-containing patches throughout the cell cortex. Similarly, in dividing cells, a structure composed of Rho and Citron-K in Cleavage Furrow excludes cortical actin cytoskeleton, and disruption of F-actin disperses Citron-K throughout the cell cortex. These results suggest that Citron-K is a novel type of a passenger protein, which is dispersed to the cytoplasm in prometaphase and associated with midzone spindles by a Rho-independent signal. Rho is then activated, binds to Citron-K and translocates it to cell cortex, where the complex is then concentrated in the Cleavage Furrow by the action of actin cytoskeleton beneath the equator of dividing cells.
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rho kinase rock is involved in cytokinesis through the phosphorylation of myosin light chain and not ezrin radixin moesin proteins at the Cleavage Furrow
Oncogene, 2000Co-Authors: Hidetaka Kosako, Toshimasa Ishizaki, Shuh Narumiya, Toshimichi Yoshida, Fumio Matsumura, Masaki InagakiAbstract:The small GTPase Rho and one of its targets, Rho-kinase (also termed ROK or ROCK), are implicated in various cellular functions including stress fiber formation, smooth muscle contraction, tumor cell invasion and cell motility. We have previously reported that Rho-kinase accumulates at the Cleavage Furrow during cytokinesis in several cultured cells. Here, using Rho-kinase inhibitors, Y-27632 and HA1077, we found that Rho-kinase is responsible for the phosphorylation of myosin regulatory light chain at Ser19 in the Cleavage Furrow during cytokinesis. On the other hand, phosphorylation of ezrin/radixin/moesin (ERM) proteins at the Cleavage Furrow was enhanced by the addition of the above Rho-kinase inhibitors. Treatment with Y-27632 strongly enhanced the accumulation of Rho-kinase but not RhoA and citron kinase at the Cleavage Furrow. Furthermore, the Furrow ingression in cytokinesis was significantly prolonged in the presence of Y-27632. These results suggest that Rho-kinase is involved in the progression of cytokinesis through the phosphorylation of several proteins including myosin light chain at the Cleavage Furrow.
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Rho-kinase/ROCK is involved in cytokinesis through the phosphorylation of myosin light chain and not ezrin/radixin/moesin proteins at the Cleavage Furrow.
Oncogene, 2000Co-Authors: Hidetaka Kosako, Toshimasa Ishizaki, Shuh Narumiya, Toshimichi Yoshida, Fumio Matsumura, Masaki InagakiAbstract:The small GTPase Rho and one of its targets, Rho-kinase (also termed ROK or ROCK), are implicated in various cellular functions including stress fiber formation, smooth muscle contraction, tumor cell invasion and cell motility. We have previously reported that Rho-kinase accumulates at the Cleavage Furrow during cytokinesis in several cultured cells. Here, using Rho-kinase inhibitors, Y-27632 and HA1077, we found that Rho-kinase is responsible for the phosphorylation of myosin regulatory light chain at Ser19 in the Cleavage Furrow during cytokinesis. On the other hand, phosphorylation of ezrin/radixin/moesin (ERM) proteins at the Cleavage Furrow was enhanced by the addition of the above Rho-kinase inhibitors. Treatment with Y-27632 strongly enhanced the accumulation of Rho-kinase but not RhoA and citron kinase at the Cleavage Furrow. Furthermore, the Furrow ingression in cytokinesis was significantly prolonged in the presence of Y-27632. These results suggest that Rho-kinase is involved in the progression of cytokinesis through the phosphorylation of several proteins including myosin light chain at the Cleavage Furrow.