PRC, UMR85, INRA, CNRS, IFCE, Université de Tours, F-37380, Nouzilly, France.
BMC Genomics. 2018 Aug 14;19(1):611. doi: 10.1186/s12864-018-4977-2.
Interactions between proteins are key components in the chemical and physical processes of living organisms. Among these interactions, membrane receptors and their ligands are particularly important because they are at the interface between extracellular and intracellular environments. Many studies have investigated how binding partners have co-evolved in genomes during the evolution. However, little is known about the establishment of the interaction on a phylogenetic scale. In this study, we systematically studied the time of birth of genes encoding human membrane receptors and their ligands in the animal tree of life. We examined a total of 553 pairs of ligands/receptors, representing non-redundant interactions.
We found that 41% of the receptors and their respective first ligands appeared in the same branch, representing 2.5-fold more than expected by chance, thus suggesting an evolutionary dynamic of interdependence and conservation between these partners. In contrast, 21% of the receptors appeared after their ligand, i.e. three-fold less often than expected by chance. Most surprisingly, 38% of the receptors appeared before their first ligand, as much as expected by chance.
According to these results, we propose that a selective pressure is exerted on ligands and receptors once they appear, that would remove molecules whose partner does not appear quickly.
蛋白质之间的相互作用是生物体内化学和物理过程的关键组成部分。在这些相互作用中，膜受体及其配体尤为重要，因为它们处于细胞外和细胞内环境的界面。许多研究已经研究了在进化过程中结合伙伴在基因组中是如何共同进化的。然而，对于在系统发生尺度上建立相互作用的机制知之甚少。在这项研究中，我们系统地研究了人类膜受体及其配体在动物生命之树上的基因诞生时间。我们总共研究了 553 对配体/受体，代表非冗余相互作用。
我们发现，41%的受体及其各自的第一配体出现在同一分支中，比随机预期多 2.5 倍，这表明这些伴侣之间存在相互依存和保守的进化动态。相比之下，21%的受体出现在其配体之后，出现的频率比随机预期少 3 倍。最令人惊讶的是，38%的受体出现在它们的第一个配体之前，这与随机预期相符。
根据这些结果，我们提出，一旦配体和受体出现，就会对它们施加选择压力，从而去除其伴侣没有快速出现的分子。
