Amino acid sequences of lower vertebrate parvalbumins and their evolution: parvalbumins of boa, turtle, and salamander.
Amino acid sequences of lower vertebrate parvalbumins and their evolution: parvalbumins of boa, turtle, and salamander.
复制标题
低等脊椎动物小清蛋白的氨基酸序列及其进化：蟒蛇、海龟和蝾螈的小清蛋白。
DOI：
10.1093/oxfordjournals.molbev.a040332
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发表时间：
1984
影响因子：
10.7
通讯作者：
W. Fitch
中科院分区：
文献类型：
--
作者：
N. Maeda;D. Zhu;W. Fitch
从两种爬行动物的骨骼肌中分离出一种主要的小清蛋白，一种是蟒蛇，一种是蟒蛇，一种是地图龟，一种是地图龟，而两种小清蛋白是从两栖动物中分离出来的，两栖动物是蝾螈。所有四种小清蛋白的氨基酸序列从其胰蛋白酶肽的序列确定，其部分地通过与其他小清蛋白的同源性排序。对这些和其他16个小清蛋白序列的系统发育研究表明，海龟小清蛋白属于β谱系，而蝾螈序列分别属于Goodman和Pechère（1977）定义的α和β谱系。然而，虽然属于β谱系，但在所有合理的简约树中，Boa parvalbumin都聚集在鱼体内。尽管负责Ca2+结合的残基非常保守，但最简约的树在许多小清蛋白残基的进化中显示出许多平行或回复突变。这些最简约的进化树表明，阿尔法和贝塔两个类群的四足动物都是辐鳍类而不是横鳍类的起源。两种电鳗小清蛋白中有一种的进化速度比它的旁系同源伙伴快10倍以上，这表明它可能正在成为一种假基因。得出的结论是，不同的氨基酸替换率、大量的同质性、相当多的基因重复以及复杂的谱系使得小清蛋白序列集不适合系统研究四足动物和其他高级分类群分歧的起源，尽管它可能适合一个属或科。
One major parvalbumin each was isolated from the skeletal muscle of two reptiles, a boa snake, Boa constrictor, and a map turtle, Graptemys geographica, while two parvalbumins were isolated from an amphibian, the salamander Amphiuma means. The amino acid sequences of all four parvalbumins were determined from the sequences of their tryptic peptides, which were ordered partially by homology to other parvalbumins. Phylogenetic study of these and 16 other parvalbumin sequences revealed that the turtle parvalbumin belongs to beta lineage, while the salamander sequences belong, one each, to the alpha and beta lineages defined by Goodman and Pechère (1977). Boa parvalbumin, however, while belonging to the beta lineage, clusters within the fish in all reasonably parsimonious trees. The most parsimonious trees show many parallel or back mutations in the evolution of many parvalbumin residues, although the residues responsible for Ca2+ binding are very well conserved. These most parsimonious trees show an actinopterygian rather than a crossoptyrigian origin of the tetrapods in both the alpha and beta groups. One of two electric eel parvalbumins is evolving more than 10 times faster than its paralogous partner, suggesting it may be on its way to becoming a pseudogene. It is concluded that varying rates of amino acid replacement, much homoplasy, considerable gene duplication, plus complicated lineages make the set of parvalbumin sequences unsuitable for systematic study of the origin of the tetrapods and other higher-taxa divergence, although it may be suitable within a genus or family.