Zharkikh A A, Solovyov V V, Kolchanov N A
J Mol Evol. 1984;21(1):42-53. doi: 10.1007/BF02100626.
Conformational restrictions imposed on the fixation of insertions and deletions by the three-dimensional structure of globins during evolution are analyzed. An evolutionary tree for the primary structure of 38 taxonomically distant globins was constructed by a computer method. Based on this tree, the calculated fixation frequency of point mutations was 50-fold higher than that established jointly for deletions and insertions, and the fixation frequency of deletions was more than three times that established for insertions. It was also found that deletions and insertions are predominantly fixed in the interhelical sections and at the ends of the alpha-helices of the globin molecules. Conformational analysis of the packing of the alpha-helices in the spatial structure of globins demonstrated that the fixation of deletions and insertions in the center of an alpha-helix produces a marked distortion of their normal packing. The possible role of deletions and insertions in the evolution of protein families is discussed.
分析了进化过程中珠蛋白三维结构对插入和缺失固定所施加的构象限制。通过计算机方法构建了38种分类学上距离较远的珠蛋白一级结构的进化树。基于此树，计算得出的点突变固定频率比缺失和插入共同确定的频率高50倍，缺失的固定频率是插入确定频率的三倍多。还发现缺失和插入主要固定在珠蛋白分子的螺旋间区域和α-螺旋末端。对珠蛋白空间结构中α-螺旋堆积的构象分析表明，在α-螺旋中心的缺失和插入固定会使其正常堆积产生明显扭曲。讨论了缺失和插入在蛋白质家族进化中的可能作用。
