Genetic Dissection of Behavior/morphology Drosophila

我们将研究两种果蝇的行为和形态特征的遗传基础：银纹果蝇和异形果蝇。这两个物种虽然有着密切的亲缘关系和栖息地，但在行为和形态事件上存在很大差异。我们之前的研究表明，不同物种在攻击性互动的强度和形式上存在差异.这两个物种之间的杂交表现出两个亲本物种的混合行为。一些攻击行为表现出显性的遗传表达，这是由于几个基因或许多基因的阈值表达所致。在其他攻击行为中，杂交种表现出一种中间表达，这可能是由于许多基因或几个基因的相加效应造成的。求偶行为已经分化到了这样一个程度，两个物种之间存在着不对称的交配，异神经虫雄鸟更容易与银纹夜蛾雌性交配，反之亦然。然而，杂种很容易与这两个物种交配，这表明这一行为是非加性遗传。我们将使用回交育种设计来确定这两个物种之间差异的数量性状基因座(QTL)。在此育种设计的基础上，我们将利用AFLP分子技术构建分子连锁图谱。然后，我们将确定攻击、求偶行为和形态性状的候选QTL，并检测各个性状之间的物理连锁和多效性QTL，特定QTL的鉴定和QTL的遗传特性将进一步加深我们对行为和形态的遗传基础的理解。

We will investigate the genetic basis of behavioral and morphological traits in two species of Drosophila: D. silvestris and D. heteroneura. These two species have diverged to a great extent in their behavior and morphology event though they share a close genetic relationship and habitat. Our previous research indicates theat the species differ in the intensity and form of aggressive interactions. Hybrids between the two species display a mixture of behaviors of the two parental species. Some of the aggressive behaviors display dominant genetic expression due to a few genes or a threshold expression of many genes. in other aggressive behaviors hybrids display an intermediate expression which may be due to many genes or an additive effect of a few genes. Courtship behaviors have diverged to such an extent that there is an asymmetry of mating between the two species with D. heteroneura males mating more readily with D. silvestris females than vice versa. However, the hybrids readily mate with both species indicating a non-additive inheritance for this behavior. We will identify quantitative trait loci (QTL) for differences between these two species using a backcross breeding design. From this breeding design we will develop a molecular linkage map using AFLP molecular techniques. We will then identify candidate QTL for aggressive and courtship behaviors and morphological traits and examine the QTL for physical linkage and pleiotropy among the various traits The identification of specific QTL and the genetic properties of the QTL will further our understanding of the genetic basis of behavior and morphology.