| First Author | Randazzo D | Year | 2013 |
| Journal | J Cell Biol | Volume | 200 |
| Issue | 4 | Pages | 523-36 |
| PubMed ID | 23420875 | Mgi Jnum | J:195201 |
| Mgi Id | MGI:5476859 | Doi | 10.1083/jcb.201205118 |
| Citation | Randazzo D, et al. (2013) Obscurin is required for ankyrinB-dependent dystrophin localization and sarcolemma integrity. J Cell Biol 200(4):523-36 |
| abstractText | Obscurin is a large myofibrillar protein that contains several interacting modules, one of which mediates binding to muscle-specific ankyrins. Interaction between obscurin and the muscle-specific ankyrin sAnk1.5 regulates the organization of the sarcoplasmic reticulum in striated muscles. Additional muscle-specific ankyrin isoforms, ankB and ankG, are localized at the subsarcolemma level, at which they contribute to the organization of dystrophin and beta-dystroglycan at costameres. In this paper, we report that in mice deficient for obscurin, ankB was displaced from its localization at the M band, whereas localization of ankG at the Z disk was not affected. In obscurin KO mice, localization at costameres of dystrophin, but not of beta-dystroglycan, was altered, and the subsarcolemma microtubule cytoskeleton was disrupted. In addition, these mutant mice displayed marked sarcolemmal fragility and reduced muscle exercise tolerance. Altogether, the results support a model in which obscurin, by targeting ankB at the M band, contributes to the organization of subsarcolemma microtubules, localization of dystrophin at costameres, and maintenance of sarcolemmal integrity. |
