Mutations that cause amino acid substitutions at the invariant positions in homeodomain of OSH3 KNOX protein suggest artificial selection during rice domestication.
Mutations that cause amino acid substitutions at the invariant positions in homeodomain of OSH3 KNOX protein suggest artificial selection during rice domestication.
复制标题
导致 OSH3 KNOX 蛋白同源结构域不变位置氨基酸取代的突变表明水稻驯化过程中存在人工选择。
作者：
Yutaka Sato;Yoshimichi Fukuda;H. Hirano
knoted1样同源盒基因（KNOX基因）编码的KNOX同源域（KNOX homeodomain， HD）蛋白被认为是植物发育和形态发生事件的重要调控因子。我们发现，从水稻品种中分离出的KNOX基因之一OSH3编码了一种新的HD，该HD在不变位置上有两个氨基酸取代。对不同驯化稻和野生稻的OSH3序列分析表明，这些取代位点仅分布在亚洲驯化稻的粳稻和爪哇稻中。令人惊讶的是，第一个内含子的核苷酸序列在具有不变氨基酸取代的水稻菌株中几乎是保守的。过表达研究表明，这些不变氨基酸对体内OSH3的功能至关重要。这些替换发生在功能重要的氨基酸上，并且这些序列在中性突变积累的内含子中是保守的，这表明在驯化过程中，OSH3不变位置的替换是通过人工选择固定的。基于这些观察结果，我们假设OSH3是在大部分粳稻和部分爪哇稻型水稻驯化过程中选择性引入的性状之一。
KNOX homeodomain (HD) proteins encoded by KNOTTED1-like homeobox genes (KNOX genes) are considered to work as important regulators for plant developmental and morphogenetic events. We found that OSH3, one of the KNOX genes isolated from a cultivar of Oryza sativa (Nipponbare), encodes a novel HD, which has two amino acid substitutions at invariant positions. Sequence analysis of OSH3 from various domesticated and wild species of rice has revealed that these substitutions are distributed only in Japonica and Javanica type of O. sativa, two groups of domesticated rice in Asia. Surprisingly, nucleotide sequences in the first intron are almost conserved in the rice strains that have the substitutions at the invariant amino acids. Overexpression studies revealed that these invariant amino acids are critical for the function of OSH3 in vivo. The facts that these substitutions occurred specifically at the functionally important amino acids and the sequences are conserved in intron where neutral mutations accumulate suggest the substitutions at the invariant positions of OSH3 have been fixed by artificial selections during domestication. Based on these observations, we hypothesize that OSH3 is responsible for one of the traits that are selectively introduced during the domestication of most of Japonica and a part of Javanica type of rice.
影响因子：
4
作者：
Aquadro, CF
通讯作者：
Aquadro, CF