Department of Ecology and Evolution, The University of Chicago, Chicago, IL 60637, USA.
Cell Rep. 2012 Feb 23;1(2):118-32. doi: 10.1016/j.celrep.2011.12.010. Epub 2012 Feb 16.
The evolution of the brain and behavior are coupled puzzles. The genetic bases for brain evolution are widely debated, yet whether newly evolved genes impact the evolution of the brain and behavior is vaguely understood. Here, we show that during recent evolution in Drosophila, new genes have frequently acquired neuronal expression, particularly in the mushroom bodies. Evolutionary signatures combined with expression profiling showed that natural selection influenced the evolution of young genes expressed in the brain, notably in mushroom bodies. Case analyses showed that two young retrogenes are expressed in the olfactory circuit and facilitate foraging behavior. Comparative behavioral analysis revealed divergence in foraging behavior between species. Our data suggest that during adaptive evolution, new genes gain expression in specific brain structures and evolve new functions in neural circuits, which might contribute to the phenotypic evolution of animal behavior.
大脑和行为的进化是一对相互关联的谜题。大脑进化的遗传基础仍存在广泛争议，但新进化的基因是否会影响大脑和行为的进化还不太清楚。在这里，我们表明，在果蝇的近期进化过程中，新基因经常获得神经元表达，特别是在蘑菇体中。进化特征与表达谱相结合的结果表明，自然选择影响了大脑中表达的年轻基因的进化，特别是在蘑菇体中。案例分析表明，两个年轻的返座基因在嗅觉回路中表达，并促进觅食行为。比较行为分析表明，在物种间存在觅食行为的差异。我们的数据表明，在适应进化过程中，新基因在特定的大脑结构中获得表达，并在神经回路中进化出新的功能，这可能有助于动物行为的表型进化。
