Cohen-Gihon Inbar, Fong Jessica H, Sharan Roded, Nussinov Ruth, Przytycka Teresa M, Panchenko Anna R
Sackler Institute of Molecular Medicine, Department of Human Genetics, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
Mol Biosyst. 2011 Mar;7(3):784-92. doi: 10.1039/c0mb00182a. Epub 2010 Dec 3.
Most eukaryotic proteins are composed of two or more domains. These assemble in a modular manner to create new proteins usually by the acquisition of one or more domains to an existing protein. Promiscuous domains which are found embedded in a variety of proteins and co-exist with many other domains are of particular interest and were shown to have roles in signaling pathways and mediating network communication. The evolution of domain promiscuity is still an open problem, mostly due to the lack of sequenced ancestral genomes. Here we use inferred domain architectures of ancestral genomes to trace the evolution of domain promiscuity in eukaryotic genomes. We find an increase in average promiscuity along many branches of the eukaryotic tree. Moreover, domain promiscuity can proceed at almost a steady rate over long evolutionary time or exhibit lineage-specific acceleration. We also observe that many signaling and regulatory domains gained domain promiscuity around the Bilateria divergence. In addition we show that those domains that played a role in the creation of two body axes and existed before the divergence of the bilaterians from fungi/metazoan achieve a boost in their promiscuities during the bilaterian evolution.
大多数真核生物蛋白质由两个或更多结构域组成。这些结构域以模块化方式组装，通常通过向现有蛋白质添加一个或多个结构域来产生新的蛋白质。存在于多种蛋白质中并与许多其他结构域共存的混杂结构域尤其令人感兴趣，并且已显示它们在信号通路和介导网络通信中发挥作用。结构域混杂性的进化仍然是一个悬而未决的问题，主要是由于缺乏已测序的祖先基因组。在这里，我们使用推断的祖先基因组结构域架构来追踪真核生物基因组中结构域混杂性的进化。我们发现在真核生物树的许多分支上平均混杂性有所增加。此外，结构域混杂性在漫长的进化时间内几乎可以以稳定的速率进行，或者表现出特定谱系的加速。我们还观察到，许多信号传导和调节结构域在两侧对称动物分化前后获得了结构域混杂性。此外，我们表明，那些在两个体轴形成中发挥作用且在两侧对称动物与真菌/后生动物分化之前就已存在的结构域，在两侧对称动物进化过程中其混杂性得到了提升。
