Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom.
Mol Biol Cell. 2013 May;24(10):1574-83. doi: 10.1091/mbc.E12-07-0557. Epub 2013 Mar 13.
Rab GTPases serve as major control elements in the coordination and definition of specific trafficking steps and intracellular compartments. Rab activity is modulated in part by GTPase-activating proteins (GAPs), and many RabGAPs share a Tre-2/Bub2/Cdc16 (TBC)-domain architecture, although the majority of TBC proteins are poorly characterized. We reconstruct the evolutionary history of the TBC family using ScrollSaw, a method for the phylogenetic analysis of pan-eukaryotic data sets, and find a sophisticated, ancient TBC complement of at least 10 members. Significantly, the TBC complement is nearly always smaller than the Rab cohort in any individual genome but also suggests Rab/TBC coevolution. Further, TBC-domain architecture has been well conserved in modern eukaryotes. The reconstruction also shows conservation of ancestral TBC subfamilies, continuing evolution of new TBCs, and frequent secondary losses. These patterns give additional insights into the sculpting of the endomembrane system.
Rab GTPases 作为协调和定义特定运输步骤和细胞内隔室的主要控制元件。Rab 的活性部分受 GTPase 激活蛋白 (GAP) 调节,许多 RabGAP 具有 Tre-2/Bub2/Cdc16 (TBC)-结构域架构,尽管大多数 TBC 蛋白的特征描述较差。我们使用 ScrollSaw 重建了 TBC 家族的进化历史,这是一种用于泛真核数据集系统发育分析的方法,发现了一个复杂的、古老的 TBC 家族,至少有 10 个成员。重要的是,在任何单个基因组中,TBC 家族的成员数量都远小于 Rab 家族,但也表明 Rab/TBC 共同进化。此外,TBC 结构域结构在现代真核生物中得到了很好的保守。该重建还显示了祖先 TBC 亚家族的保守性,新的 TBC 不断进化,并且经常发生二次丢失。这些模式为内膜系统的塑造提供了更多的见解。