Emerin, deficiency of which causes Emery-Dreifuss muscular dystrophy, is localized at the inner nuclear membrane
Emerin, deficiency of which causes Emery-Dreifuss muscular dystrophy, is localized at the inner nuclear membrane
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Emeryin 缺乏会导致 Emery-Dreifuss 肌营养不良症，其位于内核膜
作者：
Hiroshi Yorifuji;Yutaka Tadano;Yuichi Tsuchiya;Megumu Ogawa;Kanako Goto;Atsushi Umetani;Yoshiyuki Asaka;Kiichi Arahata
摘要连锁隐性Emery-Dreifuss型肌营养不良症（EDMD）是一种遗传性肌肉疾病，其临床特征为进行性肱腓骨肌萎缩，肘关节、跟腱和颈后肌早期挛缩，心脏传导阻滞，具有猝死的高风险。Xq 28上的EDMD基因编码一种名为emerin的新蛋白，其定位于骨骼肌、心肌和平滑肌以及一些其他非肌肉组织的核膜。为了研究emerin可能的生理作用，我们研究了超微结构定位的蛋白质在人类骨骼肌和HeLa细胞，使用crystalcryosections。我们发现免疫标记的胶体金颗粒定位于核内膜的核质表面，但不在核孔上。Emerin停留在核纤层的细胞质表面上，即使在溶解膜脂质并洗掉膜蛋白的去污剂处理之后。这些结果表明，emerin锚定在内核膜通过疏水拉伸，并从亲水区域突出到核质，在那里它与核纤层相互作用。我们推测，emerin有助于维持核结构和稳定性，以及核功能，特别是在肌肉组织中，具有严格的收缩-放松运动和钙流量的严重应力。
ABSTRACTX-linked recessive Emery-Dreifuss muscular dystrophy (EDMD) is an inherited muscle disorder characterized by the clinical triad of progressive wasting of humero-peroneal muscles, early contractures of the elbows, Achilles tendons and postcervical muscles, and cardiac conduction block with a high risk of sudden death. The gene for EDMD on Xq28 encodes a novel protein named emerin that localizes at the nuclear membrane of skeletal, cardiac and smooth muscles and some other non-muscle tissues. To investigate a possible physiological role for emerin, we examined the ultrastructural localization of the protein in human skeletal muscle and HeLa cells, using ultrathin cryosections. We found that the immune-labeled colloidal gold particles were localized on the nucleoplasmic surface of the inner nuclear membrane, but not on the nuclear pore. Emerin stayed on the cytoplasmic surface of the nuclear lamina, even after detergent treatment that solubilizes membrane lipids and washes out membrane proteins. These results suggest that emerin anchors at the inner nuclear membrane through the hydrophobic stretch, and protrudes from the hydrophilic region to the nucleoplasm where it interacts with the nuclear lamina. We speculate that emerin contributes to maintain the nuclear structure and stability, as well as nuclear functions, particularly in muscle tissues that have severe stress with rigorous contraction-relaxation movements and calcium flux.
DOI：
10.1073/pnas.94.3.849
发表时间：
1997-02-04
影响因子：
11.1
作者：
Maniotis, AJ;Chen, CS;Ingber, DE
通讯作者：
Ingber, DE