Evolution of New Genes in Drosophila

这些实验的目的是描述芬尼肯的基本生物学，这是一种新的基因，从果蝇的Repleta组中从adh下降，以寻找其他从果蝇的adh下降的新基因的例子。这些数据将提供对新功能进化的一般模式和过程的第一次洞察，并为进一步的新功能进化实验提供原材料。尽管进化新颖性在进化中具有明显的重要性，但人们对进化新颖性在基因水平上的起源和阐述知之甚少。我们对这一关键问题的缺乏可以归因于至少三个差距。首先，几乎没有已知的具有最近进化功能的基因的例子，但正是这种情况，我们应该最有机会了解导致新基因功能分化的起源和早期阶段的机制。其次，通常很难想象驱动分子进化新颖性的选择压力是如何推断的，因为许多例子涉及基本细胞功能基因的古老重组(例如，外显子改组)。最后，由于没有共同努力寻找具有最近进化功能的基因，因此没有办法了解这种事件有多常见，没有关于它们的系统发育分布的知识，没有对它们与生态因素的相关性的了解，也没有对决定特定基因或基因类型的进化路径的一般原则的理解。

The goals of these experiments are to describe the basic biology of Finnegan, a novel gene descended from Adh in the repleta group of Drosophila, to find other examples of new genes descended from Adh in Drosophila. These data will provide the first insight into general patterns and processes in the evolution of new function and provide the raw material for further experiments on evolution of novel function.Despite its obvious importance in evolution, the origin and elaboration of evolutionary novelty at the genetic level is only poorly understood. Our lack of insight into this key problem can be attributed to at least three gaps. First there are few known examples of genes having a recently evolved function, yet it is such cases where we should have the best chance of understanding the mechanisms responsible for the origins and early stages of functional divergence of new genes. Second, it is often difficult to imagine how the selective pressures driving molecular evolutionary novelty, might be inferred since many examples involve ancient reorganization (e.g., exon shuffling) of basic cell function genes. Finally, since there has been no concerted effort to search for genes with recently evolved function there is no way to understand how common such events are, no knowledge of their phylogenetic distribution, no understanding of their correlations with ecological factors, and no understanding of the general principles determining the evolutionary paths open to particular genes or types of genes.