Molecular Evolution of the TAC1 Gene from Rice (Oryza sativa L.)
Molecular Evolution of the TAC1 Gene from Rice (Oryza sativa L.)
复制标题
DOI：
10.1016/j.jgg.2012.07.011
复制
发表时间：
2012-10-01
影响因子：
5.9
通讯作者：
Sun, Chuanqing
中科院分区：
文献类型：
--
作者：
Jiang, Jiahuan;Tan, Lubin;Sun, Chuanqing
分蘖角是栽培水稻（Oryza sativa）结构的一个关键特征，因为它决定了种植密度并影响水稻产量。我们之前的研究发现分蘖角控制1 （TAC1）是控制水稻分蘖角的主要数量性状位点。为了进一步明确TAC1基因的进化特征，我们比较了113个栽培品种和48个野生水稻（包括43个水稻品种和5个水稻品种）中含有TAC1基因的3164 bp基因组区域。在栽培稻品种的TAC1编码区只检测到一个同义替换的单核苷酸多态性（SNP），而在野生稻品种的TAC1编码区检测到一个同义和一个非同义SNP。这些数据表明，在进化过程中，栽培稻及其祖先的TAC1编码区很少发生自然突变和修饰。水稻sativa和rufipogon的TAC1基因区核苷酸多样性分别为0.00116和0.00112，进一步表明TAC1在水稻驯化过程中具有高度保守性。TAC1的功能性核苷酸多态性（FNP）仅在粳稻组中发现。中性试验表明，在粳稻群体中，具有较强的选择性，特别是在TAC1编码区3'侧区域含有FNP。然而，在籼稻和野生稻组中没有发生选择。基于TAC1序列的系统发育树分析表明，籼稻亚种和粳稻亚种是在野生稻驯化过程中独立产生的。
Tiller angle is a key feature of the architecture of cultivated rice (Oryza sativa), since it determines planting density and influences rice yield. Our previous work identified Tiller Angle Control 1 (TAC1) as a major quantitative trait locus that controls rice tiller angle. To further clarify the evolutionary characterization of the TAC1 gene, we compared a TAC1-containing 3164-bp genomic region among 113 cultivated varieties and 48 accessions of wild rice, including 43 accessions of O. rufipogon and five accessions of O. nivara. Only one single nucleotide polymorphism (SNP), a synonymous substitution, was detected in TAC1 coding regions of the cultivated rice varieties, whereas one synonymous and one nonsynonymous SNP were detected among the TAC1 coding regions of wild rice accessions. These data indicate that little natural mutation and modification in the TAC1 coding region occurred within the cultivated rice and its progenitor during evolution. Nucleotide diversities in the TAC1 gene regions of O. sativa and O. rufipogon of 0.00116 and 0.00112, respectively, further indicate that TAC1 has been highly conserved during the course of rice domestication. A functional nucleotide polymorphism (FNP) of TAC1 was only found in the japonica rice group. A neutrality test revealed strong selection, especially in the 3'-flanking region of the TAC1 coding region containing the FNP in the japonica rice group. However, no selection occurred in the indica and wild-rice groups. A phylogenetic tree derived from TAC1 sequence analysis suggests that the indica and japonica subspecies arose independently during the domestication of wild rice.