Dissertation Research: Genetic Architecture of Flower-color Differences in Ipomoea Species

花的颜色是一个重要的生态特征，因为它被植物用来吸引传粉者。牵牛花(牵牛花)不同种间的花色差异通常会导致不同授粉者的出现和花粉交换的缺乏。为了了解花色差异的遗传基础，人们可以研究产生花色素的主要生物合成基因。这些基因的差异应该表现为DNA序列、表达水平或表达时间的不同。将结合杂交研究、DNA测序和基因表达分析来确定导致通菜属两个密切相关物种之间花差异的一个或多个基因：白色花的I.lacunosa和紫色花的I.trioba。在适应性进化过程中固定的突变的数量和类型是生物学中的一个长期问题。最近的研究表明，与长期存在的观点相反，只有少数几个具有重大影响的突变可能与适应有关。此外，随着越来越多的证据表明大多数蛋白质在很长一段时间内都是保守的，有人认为重要的突变可能主要发生在调控序列中。为了解决这些问题，我们将研究空心菜和三叶草花色差异的遗传基础。

Flower color is an important ecological trait because it is used by plants to attract pollinators. Differences in flower color between species of Ipomoea (morning glories) will often lead to the presence of different sets of pollinators and a lack of pollen exchange. In order to understand the genetic basis for differences in flower color, one can study the major biosynthetic genes that produce flower pigments. Differences in these genes should be manifest as differences in DNA sequence, expression level, or expression time. A combination of crossing studies, DNA sequencing, and gene expression assays will be used to identify the gene or genes responsible for flower differences between two closely related species of Ipomoea: the white-flowered I. lacunosa and the purple-flowered I. triloba. The number and type of mutations fixed during adaptive evolution is a long-standing question in biology. Recent work has suggested that, contrary to longstanding views, only a few mutations of large effect may be involved in adaptation. Furthermore, with increasing evidence of the conservation of most proteins over long time periods, it has been suggested that important mutations may occur primarily in regulatory sequences. In order to address these issues, the genetic basis of flower color differences between I. lacunosa and I. triloba will be examined.