Institute for Developmental Biology, University of Cologne, Zülpichstrasse 47b, 50674 Cologne, Germany.
Dev Biol. 2013 Sep 1;381(1):189-202. doi: 10.1016/j.ydbio.2013.05.026. Epub 2013 Jun 2.
Regulatory networks composed of interacting genes are responsible for pattern formation and cell type specification in a wide variety of developmental contexts. Evolution must act on these regulatory networks in order to change the proportions, distribution, and characteristics of specified cells. Thus, understanding how these networks operate in homologous systems across multiple levels of phylogenetic divergence is critical for understanding the evolution of developmental systems. Among the most thoroughly characterized regulatory networks is the dorsal-ventral patterning system of the fly Drosophila melanogaster. Due to the thorough understanding of this system, it is an ideal starting point for comparative analyses. Here we report an analysis of the DV patterning system of the wasp, Nasonia vitripennis. This wasp undergoes a mode of long germ embryogenesis that is superficially nearly identical to that of Drosophila, but one that was likely independently derived. We have found that while the expression of genes just prior to the onset of gastrulation is almost identical in Nasonia and Drosophila, both the upstream network responsible for generating this pattern, and the downstream morphogenetic movements that it sets in motion, are significantly diverged. From this we conclude that many network structures are available to evolution to achieve particular developmental ends.
由相互作用的基因组成的调控网络负责在广泛的发育背景下形成模式和细胞类型。为了改变特定细胞的比例、分布和特征，进化必须作用于这些调控网络。因此，了解这些网络在同源系统中如何在多个系统发育分歧水平上运作，对于理解发育系统的进化至关重要。在最彻底描述的调控网络中，有果蝇 Drosophila melanogaster 的背腹模式形成系统。由于对这个系统的透彻理解，它是比较分析的理想起点。在这里，我们报告了对黄蜂 Nasonia vitripennis 的 DV 模式形成系统的分析。这种黄蜂经历了一种长胚胚胎发生模式，表面上与果蝇非常相似，但很可能是独立衍生的。我们发现，虽然在原肠胚形成之前表达的基因几乎在 Nasonia 和果蝇中是相同的，但负责产生这种模式的上游网络，以及它引发的下游形态发生运动，都有很大的差异。由此我们得出结论，进化可以利用许多网络结构来实现特定的发育目的。
