RUI: A Phylogenetic analysis of subfamily Gesnerioideae (Gesneriaceae) and sequence divergence in a cycloidea homolog.

博伊西州立大学的詹姆斯·史密斯博士正在研究一个大型热带植物群--非洲紫罗兰科(Gesneriaceae)的进化史(这种植物的大部分出现在美洲，而不是非洲)。进化史将通过比较基因测序来研究，比较基因测序是一种直接检查基因以追踪整个有机体的进化史的过程。一旦从这些数据中产生了进化树，生物体的历史将被用于几个目标。1)由于不同形式的花对称出现在这组植物中，系统发育树将提供一种方法来确定从一种对称形式到另一种对称形式的转换发生的频率。2)已知花的对称性由相关植物中的几个基因控制，树将提供一种手段来研究具有不同类型对称性的植物家族中这些基因之一的进化。3)这棵树将为这类植物未来的所有研究提供一个框架，特别是授粉生物学和染色体的进化。系统学面临的最大问题之一是确定同源性(特征具有共同的进化起源)。表型(生物体的外貌)是基因在生物体生长过程中通过复杂的发育机制观察到的结果。相似的发育途径可能会导致不相关生物的相似表型。发育同源性(相同的发育过程)与系统发育同源性(相同的历史)的这种脱钩可能导致对生物体之间关系的误解。很少有机会让系统学家研究表型背后的遗传机制，以及这些机制中导致多样性模式的变化。苦瓜科部分类群的进化史将使我们有机会研究花型的变化和调节这些表型的基因的变化，以确定它们是否具有发育和系统发育同源性。

Dr. James Smith at Boise State University is investigating the evolutionary history of a large tropical plant group, the African violet family Gesneriaceae (a major portion of which occurs in the Americas and not in Africa). The evolutionary history will be studied with comparative gene sequencing, a process that examines genes directly to trace the evolutionary history of the whole organism. Once an evolutionary tree is produced from these data, the history of the organisms will be used for several objectives. 1) Because different forms of floral symmetry occur in this group of plants, the phylogenetic tree will provide a means of determining how often switches from one form of symmetry to another have occurred. 2) Floral symmetry is known to be controlled by a few genes in related plants and the tree will provide a means of examining the evolution of one of these genes in a plant family that has different types of symmetry. 3) The tree will provide a framework for all future investigations among this group of plants, especially evolution of pollination biology and chromosomes. One of the greatest problems facing systematics is determining homology (where traits have a common evolutionary origin). Phenotypes (physical appearance of an organism) are the result of genes viewed through complex developmental mechanisms operating during the growth of the organism. Similar developmental pathways may result in similar phenotypes across non-related organisms. This uncoupling of developmental homology (identical developmental processes) from phylogenetic homology (identical history) can result in misinterpreting relationships among organisms. Few opportunities have allowed systematists to investigate the genetic mechanisms that underlie phenotypes and the changes in these mechanisms that result in patterns of diversity. The evolutionary history of selected groups of Gesneriaceae will allow an opportunity to examine the changes in floral phenotypes and changes in the genes that regulate these phenotypes to see if they share developmental and phylogenetic homology.