Evolution of dorsal-ventral patterning mechanisms in sibling Drosophila species

以前的研究表明，在不同的类群中建立胚胎组织的分子机制高度保守。然而，关于格局形成的一些长期存在的重大问题在很大程度上仍然是未知的。其中包括伸缩机制和如何获得新的身体结构，而一些模式在进化过程中被保留下来。这个项目将研究不同卵子大小的物种在沿着背腹轴形成初级胚胎生殖层期间的缩放特性。为了解决这些问题，研究人员将对最近分化、但获得了急剧变化的卵大小的果蝇进行跨物种比较。这些实验将包括对不同果蝇的形态发生梯度和基因表达模式的定量测量。此外，两种亲缘关系密切的能够杂交的果蝇物种--黑腹果蝇和黑腹果蝇--将允许进行遗传实验，以测试母体和受精卵的形态发生信息对胚胎模式的特定物种贡献。该项目的结果预计将产生必要的关键量化数据，以分析发展系统的规模特性，并开发未来的计算模型，以解释模式如何随规模而重新调整规模。该项目的更广泛影响包括本科生和研究生一级的培训，将少数群体纳入科学，以及改进发育生物学、进化和建模领域的课程。

Previous studies revealed a high degree of conservation of the molecular mechanisms that establish embryonic tissues in diverse taxa. However, there are long-standing problems of great significance regarding pattern formation that remain largely unknown. Among those are the mechanisms of scaling and how novel body architectures are acquired, while some patterns are preserved during the course of evolution. This project will investigate the scaling properties during the formation of primary embryonic germ layers along the dorso-ventral axis in species that differ in egg size. To address these questions, the investigator will make cross-species comparisons among Drosophilids that diverged recently, but acquired sharp variation in egg size. The experiments will include quantitative measurements of morphogenetic gradients and gene expression patterns in different Drosophilids. In addition, two closely related Drosophila species that can hybridize, D. melanogaster and D. sechellia, will allow genetic experimentation to test species-specific contribution of maternal versus zygotic morphogenetic information to embryonic patterning. The results of this project are expected to produce critical quantitative data necessary to analyze the scaling properties of developmental systems and develop future computational models to explain how patterns are re-scaled with size. Broader impacts of this project include training at undergraduate and graduate levels, inclusion of minority groups to science, and improvement of curricula in the areas of developmental biology, evolution and modeling.