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Deficiency of TMEM53 causes a previously unknown sclerosing bone disorder by dysregulation of BMP-SMAD signaling.

ABSTRACT: Bone formation represents a heritable trait regulated by many signals and complex mechanisms. Its abnormalities manifest themselves in various diseases, including sclerosing bone disorder (SBD). Exploration of genes that cause SBD has significantly improved our understanding of the mechanisms that regulate bone formation. Here, we discover a previously unknown type of SBD in four independent families caused by bi-allelic loss-of-function pathogenic variants in TMEM53, which encodes a nuclear envelope transmembrane protein. Tmem53^-/- mice recapitulate the human skeletal phenotypes. Analyses of the molecular pathophysiology using the primary cells from the Tmem53^-/- mice and the TMEM53 knock-out cell lines indicates that TMEM53 inhibits BMP signaling in osteoblast lineage cells by blocking cytoplasm-nucleus translocation of BMP2-activated Smad proteins. Pathogenic variants in the patients impair the TMEM53-mediated blocking effect, thus leading to overactivated BMP signaling that promotes bone formation and contributes to the SBD phenotype. Our results establish a previously unreported SBD entity (craniotubular dysplasia, Ikegawa type) and contribute to a better understanding of the regulation of BMP signaling and bone formation.

SUBMITTER: Guo L

PROVIDER: S-EPMC8024261 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Deficiency of TMEM53 causes a previously unknown sclerosing bone disorder by dysregulation of BMP-SMAD signaling.

Guo Long L Iida Aritoshi A Bhavani Gandham SriLakshmi GS Gowrishankar Kalpana K Wang Zheng Z Xue Jing-Yi JY Wang Juan J Miyake Noriko N Matsumoto Naomichi N Hasegawa Takanori T Iizuka Yusuke Y Matsuda Masashi M Nakashima Tomoki T Takechi Masaki M Iseki Sachiko S Yambe Shinsei S Nishimura Gen G Koseki Haruhiko H Shukunami Chisa C Girisha Katta M KM Ikegawa Shiro S

Nature communications 20210406 1

Bone formation represents a heritable trait regulated by many signals and complex mechanisms. Its abnormalities manifest themselves in various diseases, including sclerosing bone disorder (SBD). Exploration of genes that cause SBD has significantly improved our understanding of the mechanisms that regulate bone formation. Here, we discover a previously unknown type of SBD in four independent families caused by bi-allelic loss-of-function pathogenic variants in TMEM53, which encodes a nuclear env ...[more]

PMID: 33824347

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Dataset Information

Deficiency of TMEM53 causes a previously unknown sclerosing bone disorder by dysregulation of BMP-SMAD signaling.

Publications

Deficiency of TMEM53 causes a previously unknown sclerosing bone disorder by dysregulation of BMP-SMAD signaling.

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