CRYSTAL-STRUCTURE OF THE ANNEXIN-XII HEXAMER AND IMPLICATIONS FOR BILAYER INSERTION
CRYSTAL-STRUCTURE OF THE ANNEXIN-XII HEXAMER AND IMPLICATIONS FOR BILAYER INSERTION
复制标题
DOI：
10.1038/378512a0
复制
发表时间：
1995-11-30
期刊：
影响因子：
64.8
通讯作者：
HAIGLER, HT
中科院分区：
文献类型：
--
作者：
LUECKE, H;CHANG, BT;HAIGLER, HT
附件蛋白是钙和磷脂结合蛋白家族（1，2），参与许多生物学过程，包括膜融合（3）和离子通道形成（4-7）。膜联蛋白XII六聚体的晶体结构在2.8埃分辨率下精制，形成具有3-2对称性的凹盘，直径约100埃，厚度约70埃，具有中心亲水孔。六个分子间Ca 2+离子参与六聚体的形成。另外18个Ca 2+离子位于盘的周边，仅可从六聚体盘的侧面接近。在六聚体结构的基础上，我们在这里提出了一种新的蛋白质-磷脂双层相互作用模式，它不同于典型膜蛋白的疏水插入。该推测模型假定亲水性膜联蛋白XII六聚体以局部重定向的双层磷脂的方式插入磷脂双层中，这是Ca 2+依赖性的。
ANNEXINS are a family of calcium- and phospholipid-binding proteins(1,2) implicated in a number of biological processes including membrane fusion(3) and ion channel formation(4-7). The crystal structure of the annexin XII hexamer, refined at 2.8 Angstrom resolution, forms a concave disk with 3-2 symmetry, about 100 Angstrom in diameter and 70 Angstrom thick with a central hydrophilic pore. Six intermolecular Ca2+ ions are involved in hexamer formation. An additional 18 Ca2+ ions are located on the perimeter of the disk, accessible only from the side of the hexameric disk. On the basis of the hexamer structure we propose here a new mode of protein-phospholipid bilayer interaction that is distinct from the hydrophobic insertion of typical membrane proteins. This speculative model postulates the Ca2+-dependent insertion of the hydrophilic annexin XII hexamer into phospholipid bilayers with local reorientation of the bilayer phospholipids.