• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >Seipin Is a Discrete Homooligomer
【24h】

Seipin Is a Discrete Homooligomer

机译：Seipin是一种离散的均聚物

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Seipin is a transmembrane protein that resides in the endoplasmic reticulum and concentratesnat junctions between the ER and cytosolic lipid droplets. Mutations in the human seipin gene, including thenmissense mutation A212P, lead to congenital generalized lipodystrophy (CGL), characterized by the lack ofnnormal adipose tissue and accumulation of fat in liver andmuscles. In both yeast and CGL patient fibroblasts,nseipin is required for normal lipid dropletmorphology; in its absence droplets appear to bud abnormally fromnthe ER. Here we report the first purification and physical characterization of seipin. Yeast seipin is in a largendiscrete protein complex. Affinity purification demonstrated that seipin is the main if not exclusive protein innthe complex. Detergent sucrose gradients in H2O, and D2O and gel filtration were used to determine the sizenof the seipin complex and account for detergent binding. Both seipin-myc13 (seipin fused to 13 tandem copiesnof the myc epitope) expressed from the endogenous promoter and overexpressed seipin-mCherry formn∼500 kDa proteins consisting of about 9 copies of seipin. The yeast orthologue of the human A212P allelenforms only smaller complexes and is unstable; we hypothesize that this accounts for its null phenotype innhumans. Seipin appears as a toroid by negative staining electronmicroscopy.We speculate that seipin plays at leastna structural role in organizing droplets or in communication between droplets and ER.
机译：脂蛋白是一种跨膜蛋白，存在于内质网中，并集中在ER和胞质脂质小滴之间。人seipin基因的突变，包括随后的缺失突变A212P，会导致先天性全身性脂肪营养不良（CGL），其特征是缺乏正常的脂肪组织以及肝脏和肌肉中脂肪的积累。在酵母和CGL患者的成纤维细胞中，正常脂滴形态都需要使用nseipin。在没有它的情况下，水滴似乎从ER异常发芽。在这里，我们报告脂蛋白的首次纯化和物理表征。酵母seipin存在于较大的离散蛋白复合物中。亲和纯化表明，seipin是复合物中主要的（如果不是唯一的）蛋白质。使用H2O和D2O中的去污剂蔗糖梯度以及凝胶过滤来确定seipin复合物的大小并考虑去污剂的结合。内源性启动子表达的seipin-myc13（与myc表位的13个串联拷贝融合的seipin）和由约9个seipin组成的过表达的seipin-mCherry形成约500 kDa的蛋白质。人A212P的酵母直向同源物仅形成较小的复合物且不稳定。我们假设这解释了人类的无效表型。 Seipin在负染色电镜下显示为环形。我们推测seipin在组织液滴或在液滴与ER之间的通讯中至少起结构性作用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号