Collaborative: The Role of Gene Duplication in the Evolution of Chordate Developmental Regulation

9614940 Ameiya HOX基因在脊索动物中以高度保守的基因簇形式存在。文昌鱼只有一个基因簇，而哺乳动物、鸟类和鱼类有四个基因簇。HOX基因在胚胎发育中起着重要的作用，它决定了胚胎沿前后轴的发育特征。Ruddle、Wagner和Ameiya博士将通过直接测试来确定中间形式，如环口和弹性支链是否具有中间簇数，以及在脊索进化过程中，簇复制是否独立发生一次或多次。他们还将确定不同的支系是否拥有不同的HOX基因编号，以及基因的丢失或获得是否相同或不同。HOX基因组成的差异和相似性将与所研究的不同物种的发育状况相关。他们将详细研究特定的HOX同源基因，特别是在比较的基础上检查增强子结构和功能的异同。通过这些方法，他们希望更好地理解发育调控和进化过程之间的关系。

9614940 Amemiya The Hox genes exist as highly conserved gene clusters within the chordates. The protochordate, Amphioxus, has a single gene cluster, while the mammals, birds, and fishes have four. The Hox genes play an important role in embryogenesis, specifying developmental identities along the anterior/posterior axis. Drs. Ruddle, Wagner, and Amemiya will determine by direct testing whether intermediate forms such as cyclostomes and elasmobranchs have intermediate cluster numbers and whether cluster duplication occurred once or several times independently during Chordate evolution. They will also determine whether different clades posses different Hox gene numbers, and if the loss or gain of genes has been the same or different. Differences and similarities in Hox gene composition will be correlated with the developmental status of the different species examined. They will study particular Hox orthologous genes in detail, especially examining similarities and differences in enhancer structure and function on a comparative basis. By these approaches, they hope to better understand the relationship between developmental regulation and evolutionary process.