Lange Stephan, Ouyang Kunfu, Meyer Gretchen, Cui Li, Cheng Hongqiang, Lieber Richard L, Chen Ju
Department of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
J Cell Sci. 2009 Aug 1;122(Pt 15):2640-50. doi: 10.1242/jcs.046193. Epub 2009 Jul 7.
The giant protein obscurin is thought to link the sarcomere with the sarcoplasmic reticulum (SR). The N-terminus of obscurin interacts with the M-band proteins titin and myomesin, whereas the C-terminus mediates interactions with ankyrin proteins. Here, we investigate the importance of obscurin for SR architecture and organization. Lack of obscurin in cross-striated muscles leads to changes in longitudinal SR architecture and disruption of small ankyrin-1.5 (sAnk1.5) expression and localization. Changes in SR architecture in obscurin knockout mice are also associated with alterations in several SR or SR-associated proteins, such as ankyrin-2 and beta-spectrin. Finally, obscurin knockout mice display centralized nuclei in skeletal muscles as a sign of mild myopathy, but have normal sarcomeric structure and preserved muscle function.
巨大蛋白 obscurin 被认为可将肌节与肌浆网（SR）连接起来。obscurin 的 N 端与 M 带蛋白肌联蛋白和肌间蛋白相互作用，而 C 端介导与锚蛋白的相互作用。在此，我们研究 obscurin 对 SR 结构和组织的重要性。横纹肌中缺乏 obscurin 会导致纵向 SR 结构的改变以及小锚蛋白 -1.5（sAnk1.5）表达和定位的破坏。obscurin 基因敲除小鼠中 SR 结构的变化还与几种 SR 或 SR 相关蛋白的改变有关，如锚蛋白 -2 和β-血影蛋白。最后，obscurin 基因敲除小鼠的骨骼肌中出现核集中，这是轻度肌病的迹象，但肌节结构正常且肌肉功能保留。
