Shapiro L, Kwong P D, Fannon A M, Colman D R, Hendrickson W A
Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA.
Proc Natl Acad Sci U S A. 1995 Jul 18;92(15):6793-7. doi: 10.1073/pnas.92.15.6793.
Cell-cell adhesion in zonula adherens and desmosomal junctions is mediated by cadherins, and recent crystal structures of the first domain from murine N-cadherin provide a plausible molecular basis for this adhesive action. A structure-based sequence analysis of this adhesive domain indicates that its fold is common to all extracellular cadherin domains. The cadherin folding topology is also shown to be similar to immunoglobulin-like domains and to other Greek-key beta-sandwich structures, as diverse as domains from plant cytochromes, bacterial cellulases, and eukaryotic transcription factors. Sequence similarities between cadherins and these other molecules are very low, however, and intron patterns are also different. On balance, independent origins for a favorable folding topology seem more likely than evolutionary divergence from an ancestor common to cadherins and immunoglobulins.
黏着小带和桥粒连接中的细胞间黏附由钙黏着蛋白介导，最近小鼠N -钙黏着蛋白首个结构域的晶体结构为这种黏附作用提供了一个合理的分子基础。对该黏附结构域进行的基于结构的序列分析表明，其折叠方式在所有细胞外钙黏着蛋白结构域中是常见的。钙黏着蛋白的折叠拓扑结构也显示出与免疫球蛋白样结构域以及其他希腊钥匙β -折叠结构相似，这些结构域种类繁多，包括植物细胞色素、细菌纤维素酶和真核转录因子的结构域。然而，钙黏着蛋白与这些其他分子之间的序列相似性非常低，内含子模式也不同。总体而言，一种有利的折叠拓扑结构独立起源似乎比从钙黏着蛋白和免疫球蛋白的共同祖先进化分歧更有可能。
