Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, AV Hill Building, Oxford Road, Manchester, M13 9PT, UK.
Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK.
Nat Commun. 2018 Mar 20;9(1):1156. doi: 10.1038/s41467-018-03362-1.
The interleukin-1 (IL-1) receptor and ligand families are components of the immune system. Knowledge of their evolutionary history is essential to understand their function. Using chromosomal anatomy and sequence similarity, we show that IL-1 receptor family members are related and nine members are likely formed from duplication and modification of a proto-IL-1R1 receptor. The IL-1 ligands have a different evolutionary history. The first proto-IL-1β gene coincided with proto-IL-1R1 and duplication events resulted in the majority of IL-1 ligand family members. However, large evolutionary distances are observed for IL-1α, IL-18 and IL-33 proteins. Further analysis show that IL-33 and IL-18 have poor sequence similarity and no chromosomal evidence of common ancestry with the IL-1β cluster and therefore should not be included in the IL-1 ligand ancestral family. IL-1α formed from the duplication of IL-1β, and moonlighting functions of pro-IL-1α acted as divergent selection pressures for the observed sequence dissimilarity.
白细胞介素-1 (IL-1) 受体和配体家族是免疫系统的组成部分。了解它们的进化历史对于理解其功能至关重要。我们利用染色体解剖学和序列相似性，表明 IL-1 受体家族成员是相关的，并且九个成员可能是由原始 IL-1R1 受体的复制和修饰形成的。IL-1 配体具有不同的进化历史。第一个原始 IL-1β 基因与原始 IL-1R1 同时出现，并且复制事件导致了大多数 IL-1 配体家族成员的产生。然而，IL-1α、IL-18 和 IL-33 蛋白之间存在较大的进化距离。进一步的分析表明，IL-33 和 IL-18 与 IL-1β 簇之间没有共同的序列相似性和染色体证据，因此不应被包含在 IL-1 配体的祖先家族中。IL-1α 是由 IL-1β 的复制形成的，并且前 IL-1α 的兼职功能作为观察到的序列差异的发散选择压力。
