Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion
The aim of this study was to elucidate the role of the zipper-like structure (ZLS), a podosome-related structure that transiently appears at the cell contact zone, in osteoclast fusion. Live-cell imaging of osteoclasts derived from RAW264.7 cells transfected with EGFP-actin revealed consistent symme...
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| Format: | Article |
| Language: | English |
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The Company of Biologists
2017-07-01
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| Series: | Biology Open |
| Subjects: | |
| Online Access: | http://bio.biologists.org/content/6/7/1104 |
| _version_ | 1831592115407159296 |
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| author | Jiro Takito Hirotada Otsuka Satoshi Inoue Tsubasa Kawashima Masanori Nakamura |
| author_facet | Jiro Takito Hirotada Otsuka Satoshi Inoue Tsubasa Kawashima Masanori Nakamura |
| author_sort | Jiro Takito |
| collection | DOAJ |
| description | The aim of this study was to elucidate the role of the zipper-like structure (ZLS), a podosome-related structure that transiently appears at the cell contact zone, in osteoclast fusion. Live-cell imaging of osteoclasts derived from RAW264.7 cells transfected with EGFP-actin revealed consistent symmetrical retrograde actin flow in the ZLS, but not in the podosome cluster, the podosome ring or the podosome belt. Confocal imaging showed that the distributions of F-actin, vinculin, paxillin and zyxin in the ZLS were different from those in the podosome belt. Thick actin filament bundles running outside the ZLS appeared to recruit non-muscle myosin IIA. The F-actin-rich domain of the ZLS contained actin-related protein 2/3 complex (Arp2/3). Inhibition of Arp2/3 activity disorganized the ZLS, disrupted actin flow, deteriorated cell-cell adhesion and inhibited osteoclast hypermultinucleation. In contrast, ML-7, an inhibitor of myosin light chain kinase, had little effect on the structure of ZLS and promoted osteoclast hypermultinucleation. These results reveal a link between actin flow in the ZLS and osteoclast fusion. Osteoclast fusion was promoted by branched actin elongation and negatively regulated by actomyosin contraction. |
| first_indexed | 2024-12-18T01:37:29Z |
| format | Article |
| id | doaj.art-473bb6e00f57496797a6c50dec6decb9 |
| institution | Directory Open Access Journal |
| issn | 2046-6390 |
| language | English |
| last_indexed | 2024-12-18T01:37:29Z |
| publishDate | 2017-07-01 |
| publisher | The Company of Biologists |
| record_format | Article |
| series | Biology Open |
| spelling | doaj.art-473bb6e00f57496797a6c50dec6decb92022-12-21T21:25:25ZengThe Company of BiologistsBiology Open2046-63902017-07-01671104111410.1242/bio.025460025460Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusionJiro Takito0Hirotada Otsuka1Satoshi Inoue2Tsubasa Kawashima3Masanori Nakamura4 Department of Oral Anatomy and Developmental Biology, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555, Japan Department of Oral Anatomy and Developmental Biology, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555, Japan Department of Oral Anatomy and Developmental Biology, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555, Japan Department of Paediatric Dentistry, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555, Japan Department of Oral Anatomy and Developmental Biology, School of Dentistry, Showa University, 1-5-8 Hatanodai, Shinagawa, Tokyo 142-8555, Japan The aim of this study was to elucidate the role of the zipper-like structure (ZLS), a podosome-related structure that transiently appears at the cell contact zone, in osteoclast fusion. Live-cell imaging of osteoclasts derived from RAW264.7 cells transfected with EGFP-actin revealed consistent symmetrical retrograde actin flow in the ZLS, but not in the podosome cluster, the podosome ring or the podosome belt. Confocal imaging showed that the distributions of F-actin, vinculin, paxillin and zyxin in the ZLS were different from those in the podosome belt. Thick actin filament bundles running outside the ZLS appeared to recruit non-muscle myosin IIA. The F-actin-rich domain of the ZLS contained actin-related protein 2/3 complex (Arp2/3). Inhibition of Arp2/3 activity disorganized the ZLS, disrupted actin flow, deteriorated cell-cell adhesion and inhibited osteoclast hypermultinucleation. In contrast, ML-7, an inhibitor of myosin light chain kinase, had little effect on the structure of ZLS and promoted osteoclast hypermultinucleation. These results reveal a link between actin flow in the ZLS and osteoclast fusion. Osteoclast fusion was promoted by branched actin elongation and negatively regulated by actomyosin contraction.http://bio.biologists.org/content/6/7/1104ActinCell fusionNon-muscle myosin IIAOsteoclastPodosome |
| spellingShingle | Jiro Takito Hirotada Otsuka Satoshi Inoue Tsubasa Kawashima Masanori Nakamura Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion Biology Open Actin Cell fusion Non-muscle myosin IIA Osteoclast Podosome |
| title | Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion |
| title_full | Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion |
| title_fullStr | Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion |
| title_full_unstemmed | Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion |
| title_short | Symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion |
| title_sort | symmetrical retrograde actin flow in the actin fusion structure is involved in osteoclast fusion |
| topic | Actin Cell fusion Non-muscle myosin IIA Osteoclast Podosome |
| url | http://bio.biologists.org/content/6/7/1104 |
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