Genes that determine flower color: the role of regulatory changes in the evolution of phenotypic adaptations
Genes that determine flower color: the role of regulatory changes in the evolution of phenotypic adaptations
复制标题
DOI：
10.1016/s1055-7903(03)00196-9
复制
发表时间：
2003-12-01
影响因子：
4.1
通讯作者：
Clegg, MT
中科院分区：
文献类型：
--
作者：
Durbin, ML;Lundy, KE;Clegg, MT
进化遗传学的一个中心目标是追踪特定基因的突变与表型水平的适应之间的因果途径。最近的目标是通过分析特定候选基因或其调控元件的分子序列数据来识别适应性。在本文中，我们将牵牛花属（Ipomoea）花色的分子进化视为分子和表型进化相关的模型。首先，花的颜色变化通常符合简单的孟德尔传播，从而有利于遗传和分子分析。对普通牵牛花（Ipomoea purpurea）花色多态性的群体遗传学研究表明，某些形态受到复杂的选择模式的影响。花色和形态的显着差异也与银莲花属的物种形成有关。这些适应性转变的分子基础可以被剖析，因为决定花色素沉着的生物合成途径已被充分了解，并且许多类黄酮生物合成的基因已被分离和广泛研究。我们对番薯类黄酮生物合成中几个关键基因的基因表达水平进行了比较分析。具体来说，我们要问：花颜色表型的适应性变化与基因表达调控变化与结构基因突变相关的频率有多高？这项研究的结果表明，这一关键表型的大多数物种差异与基因表达调控的变化有关。 (C) 2003 Elsevier Inc. 保留所有权利。
A central goal of evolutionary genetics is to trace the causal pathway between mutations at particular genes and adaptation at the phenotypic level. The proximate objective is to identify adaptations through the analysis of molecular sequence data from specific candidate genes or their regulatory elements. In this paper, we consider the molecular evolution of floral color in the morning glory genus (Ipomoea) as a model for relating molecular and phenotypic evolution. To begin, flower color variation usually conforms to simple Mendelian transmission, thus facilitating genetic and molecular analyses. Population genetic studies of flower color polymorphisms in the common morning glory (Ipomoea purpurea) have shown that some morphs are subject to complex patterns of selection. Striking differences in floral color and morphology are also associated with speciation in the genus lpomoea. The molecular bases for these adaptive shifts can be dissected because the biosynthetic pathways that determine floral pigmentation are well understood and many of the genes of flavonoid biosynthesis have been isolated and extensively studied. We present a comparative analysis of the level of gene expression in Ipomoea for several key genes in flavonoid biosynthesis. Specifically we ask: how frequently are adaptive shifts in flower color phenotypes associated with changes in regulation of gene expression versus mutations in structural genes? The results of this study show that most species differences in this crucial phenotype are associated with changes in the regulation of gene expression. (C) 2003 Elsevier Inc. All rights reserved.