Comparison of in vivo selection and rational design of heterodimeric coiled coils
Comparison of in vivo selection and rational design of heterodimeric coiled coils
复制标题
DOI：
10.1016/s0969-2126(02)00838-9
复制
发表时间：
2002-09-01
期刊：
影响因子：
5.7
通讯作者：
Alber, T
中科院分区：
文献类型：
--
作者：
Arndt, KM;Pelletier, JN;Alber, T
为了研究静电相互作用如何限制螺旋线圈的关联，我们通过体内选择和合理设计改进了异二聚体螺旋线圈(WinZip-A1B1)。从编码可变边(g和e)残基的文库中进行选择，丰富了g/e‘离子对，但最佳选择的杂二聚体出人意料地保留了两个预测的排斥g/e’对。最好的遗传选择的异源二聚体表现出与合理设计的二聚体相似的热力学稳定性和特异性，在所有边缘位置都有预测的离子对。然而，这种合理设计的配对在调节体内二聚化方面不如最好的遗传选择配对有效。因此，预测的电荷对的影响取决于序列环境，边缘位置的互补电荷只使形成稳定的、特定的盘绕线圈的序列的一小部分合理化。
To investigate how electrostatic interactions restrict the associations of coiled coils, we improved a heterodimeric coiled coil (WinZip-A1B1) by in vivo selection and, alternatively, by rational design. Selection from libraries encoding variable edge (g and e) residues enriched g/e' ion pairs, but the optimum selected heterodimers unexpectedly retained two predicted repulsive g/e' pairs. The best genetically selected heterodimer displayed similar thermodynamic stability and specificity as a rationally designed dimer with predicted ion pairs at all edge positions. This rationally designed pair, however, was less effective than the best genetically selected pair in mediating dimerization in vivo. Thus, the effects of predicted charge pairs depend on sequence context, and complementary charges at the edge positions rationalize only a fraction of the sequences that form stable, specific coiled coils.