...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of cellular biochemistry. >Nucleolin is a calcium-binding protein.
【24h】

Nucleolin is a calcium-binding protein.

机译：核仁蛋白是钙结合蛋白。

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

We have purified a prominent 110-kDa protein (p110) from 1.6 M NaCl extracts of rat liver nuclei that appears to bind Ca2+. p110 was originally identified by prominent blue staining with 'Stains-All' in sodium dodecyl sulfate-polyacrylamide gels and was observed to specifically bind ruthenium red and 45Ca2+ in nitrocellulose blot overlays. In spin-dialysis studies, purified p110 saturably bound approximately 75 nmol Ca2+/mg protein at a concentration of 1 mM total Ca2+ with half-maximal binding observed at 105 microM Ca2+. With purification, p110 became increasingly susceptible to proteolytic (likely autolytic) fragmentation, although most intermediary peptides between 40 and 90 kDa retained "Stains-All", ruthenium red, and 45Ca2+ binding. N-terminal sequencing of intact p110 and a 70-kDa autolytic peptide fragment revealed a strong homology to nucleolin. Two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)/IEF revealed autolysis produced increasingly acidic peptide fragments ranging in apparent pI's from 5.5 for intact p110 to 3.5 for a 40 kDa peptide fragment. Intact p110 and several peptide fragments were immunostained with a highly specific anti-nucleolin antibody, R2D2, thus confirming the identity of this protein with nucleolin. These annexin-like Ca2+-binding characteristics of nucleolin are likely contributed by its highly acidic argyrophilic N-terminus with autolysis apparently resulting in largely selective removal of its basic C-terminal domain. Although the Ca2+-dependent functions of nucleolin are unknown, we discuss the possibility that like the structurally analogous HMG-1, its Ca2+-dependent actions may regulate chromatin structure, possibly during apoptosis.
机译：我们从大鼠肝核的1.6 M NaCl提取物中纯化了一个突出的110 kDa蛋白（p110），该蛋白似乎与Ca2 +结合。 p110最初是通过十二烷基硫酸钠-聚丙烯酰胺凝胶中的'Stains-All'醒目蓝色染色识别的，并观察到它与硝酸纤维素印迹覆盖层中的钌红和45Ca2 +特异性结合。在自旋透析研究中，纯化的p110以1 mM总Ca2 +的浓度饱和结合约75 nmol Ca2 + / mg蛋白，在105 microM Ca2 +处观察到一半最大结合。通过纯化，p110变得越来越容易受到蛋白水解（可能是自溶）断裂的影响，尽管大多数介于40至90 kDa之间的中间肽保留了“ Stains-All”，钌红和45Ca2 +结合。完整的p110和70 kDa自溶肽片段的N端测序显示与核仁素有很强的同源性。二维十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）/ IEF显示自溶产生的酸性肽片段越来越多，其表观pI范围从完整p110的5.5到40 kDa肽片段的3.5。用高度特异性的抗核仁素抗体R2D2对完整的p110和几个肽片段进行免疫染色，从而确认该蛋白与核仁素的身份。核仁素的这些膜联蛋白样Ca2 +结合特征可能是由于其高度酸性的嗜酸性N末端具有自溶作用，显然导致其基本C末端结构域的选择性去除。尽管核仁蛋白的Ca2 +依赖性功能尚不清楚，但我们讨论了与结构类似的HMG-1一样，其Ca2 +依赖性作用可能在细胞凋亡期间调节染色质结构的可能性。

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