Projection structure of full length connexin 43 by electron cryo-crystallography
Projection structure of full length connexin 43 by electron cryo-crystallography
复制标题
DOI：
10.1080/714040425
复制
发表时间：
2003-07-01
影响因子：
--
通讯作者：
Yeager, M
中科院分区：
文献类型：
--
作者：
Cheng, A;Schweissinger, D;Yeager, M
我们之前使用电子冷冻结晶法确定了由Cx43的C-末端截短突变体形成的重组间隙连接通道的三维结构（11）。十二聚体通道由两个六聚体连接子的端对端对接形成，每个连接子由24个跨膜α-螺旋组成。我们现在已经产生了重组全长通道的二维晶体，以及其中C-尾已被胰蛋白酶消化完全去除的晶体。7.5埃分辨率的投影密度图与我们之前对C-末端截短突变体的分析非常相似（9）。全长通道和胰蛋白酶处理通道之间的差异图表明，去除C尾后，蛋白质密度发生了微小但显着的变化。
We previously used electron cryo-crystallography to determine the three-dimensional structure of recombinant gap junction channels formed by a C-terminal truncation mutant of Cx43 (11). The dodecameric channel is formed by the end-to-end docking of two hexameric connexons, each comprised of 24 transmembrane alpha-helices. We have now generated two-dimensional crystals of the recombinant, full-length channel, as well as crystals in which the C-tail has been completely removed by trypsin digestion. Projection density maps at 7.5 Angstrom resolution closely resemble our previous analysis of the C-terminal truncation mutant (9). A difference map between the full length and trypsin-treated channels suggests that there are small but significant shifts in protein density upon removal of the C-tail.