{"title":"EPLINβ Is Involved in the Assembly of Cadherin-catenin Complexes in Osteoblasts and Affects Bone Formation.","authors":"Shihoko Miyazaki, Taro Funamoto, Tomohisa Sekimoto, Syuji Kurogi, Tomomi Ohta, Takuya Nagai, Takuya Tajima, Mai Imasaka, Kumiko Yoshinobu, Kimi Araki, Masatake Araki, Narantsog Choijookhuu, Yoshitaka Hishikawa, Etsuo Chosa","doi":"10.1267/ahc.22-00027","DOIUrl":null,"url":null,"abstract":"<p><p>Epithelial protein lost in neoplasm (EPLIN) is an actin-associated cytoskeletal protein that plays an important role in epithelial cell adhesion. EPLIN has two isoforms: EPLINα and EPLINβ. In this study, we investigated the role of EPLINβ in osteoblasts using EPLINβ-deficient (<i>EPLINβ<sup>GT/GT</sup></i> ) mice. The skeletal phenotype of <i>EPLINβ<sup>GT/GT</sup></i> mice is indistinguishable from the wildtype (WT), but bone properties and strength were significantly decreased compared with WT littermates. Histomorphological analysis revealed altered organization of bone spicules and osteoblast cell arrangement, and decreased alkaline phosphatase activity in <i>EPLINβ<sup>GT/GT</sup></i> mouse bones. Transmission electron microscopy revealed wider intercellular spaces between osteoblasts in <i>EPLINβ<sup>GT/GT</sup></i> mice, suggesting aberrant cell adhesion. In <i>EPLINβ<sup>GT/GT</sup></i> osteoblasts, α- and β-catenins and F-actin were observed at the cell membrane, but OB-cadherin was localized at the perinuclear region, indicating that cadherin-catenin complexes were not formed. EPLINβ knockdown in MC3T3-e1 osteoblast cells showed similar results as in calvaria cell cultures. Bone formation markers, such as <i>RUNX2</i>, <i>Osterix</i>, <i>ALP</i>, and <i>Col1a1</i> mRNA were reduced in EPLINβ knockdown cells, suggesting an important role for EPLINβ in osteoblast formation. In conclusion, we propose that EPLINβ is involved in the assembly of cadherin-catenin complexes in osteoblasts and affects bone formation.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":null,"pages":null},"PeriodicalIF":16.4000,"publicationDate":"2022-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e0/ca/ahc_055-99.PMC9253499.pdf","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Accounts of Chemical Research","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1267/ahc.22-00027","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2022/6/25 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 2
Abstract
Epithelial protein lost in neoplasm (EPLIN) is an actin-associated cytoskeletal protein that plays an important role in epithelial cell adhesion. EPLIN has two isoforms: EPLINα and EPLINβ. In this study, we investigated the role of EPLINβ in osteoblasts using EPLINβ-deficient (EPLINβGT/GT ) mice. The skeletal phenotype of EPLINβGT/GT mice is indistinguishable from the wildtype (WT), but bone properties and strength were significantly decreased compared with WT littermates. Histomorphological analysis revealed altered organization of bone spicules and osteoblast cell arrangement, and decreased alkaline phosphatase activity in EPLINβGT/GT mouse bones. Transmission electron microscopy revealed wider intercellular spaces between osteoblasts in EPLINβGT/GT mice, suggesting aberrant cell adhesion. In EPLINβGT/GT osteoblasts, α- and β-catenins and F-actin were observed at the cell membrane, but OB-cadherin was localized at the perinuclear region, indicating that cadherin-catenin complexes were not formed. EPLINβ knockdown in MC3T3-e1 osteoblast cells showed similar results as in calvaria cell cultures. Bone formation markers, such as RUNX2, Osterix, ALP, and Col1a1 mRNA were reduced in EPLINβ knockdown cells, suggesting an important role for EPLINβ in osteoblast formation. In conclusion, we propose that EPLINβ is involved in the assembly of cadherin-catenin complexes in osteoblasts and affects bone formation.
期刊介绍:
Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance.
Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.