III型干扰素,也被称为干扰素λ是一种先天的抗病毒蛋白。我们检索了属于42个四足动物物种的IFN-λ及其受体序列,并进行了计算进化分析以了解该基因的多样性。通过qPCR在印度牛和水牛中测定IFN-λ的CNV。四足动物物种具有含内含子的III型IFN基因。一些爬行动物和胎盘哺乳动物具有两个IFN-λ基因座。虽然有袋动物,单调,和鸟类有一个单一的IFN-λ基因座。一些胎盘哺乳动物和两栖动物表现出无内含子和含内含子的多个IFN-λ基因。胎盘哺乳动物通常拥有三到四个功能性IFN-λ基因,其中一些缺乏信号肽。这些四足动物物种的IFN-λ形成了三个主要进化枝。哺乳动物IFN-λ4作为祖先形式出现,在大多数哺乳动物物种中具有同势保守性。无内含子的IFN-λ1和两种III型IFN受体在四足动物中具有保守的同调。在他们的进化分析中指出,纯化选择在最大程度地减少遗传多样性和维持生物学功能的完整性中起着至关重要的作用。这表明这些蛋白质成功地保留了其生物学功能和不可或缺性,即使存在I型IFNs。IFN-λ基因在两栖动物和骆驼中的扩增导致了多种IFN-λ的进化。CNV可以由基因复制和转化事件引起。基于qPCR的绝对定量导致IFN-λ3和IFN-λ4在水牛(Murrah)和六个牛品种(Sahiwal,Tharparkar,Kankrej,RedSindhi,泽西和荷斯坦·弗里斯安)。总的来说,这些发现强调了四足动物中IFN-λ的进化多样性和功能意义。
Type III interferon, also known as interferon lambda is an innate antiviral protein. We retrieved the IFN-λ and their receptors\' sequences belonging to forty-two
tetrapod species and conducted computational evolutionary analysis to understand the gene\'s diversity. The CNV of IFN-λ was determined through qPCR in Indian cattle and buffalo. The
tetrapod species feature intron-containing type-III IFN genes. Some reptiles and placental mammal have two IFN-λ loci. While marsupials, monotremes, and birds have a single IFN-λ locus. Some of the placental mammals and amphibians exhibit multiple IFN-λ genes as intron-less and intron-containing. Placental mammals typically possess three to four functional IFN-λ genes, some of them lack signal peptides. IFN-λ of these
tetrapod species formed three major clades. Mammalian IFN-λ4 appears as an ancestral form, with syntenic conservation in most mammalian species. The intron-less IFN-λ1 and both the type III IFN receptors have conserved synteny in
tetrapod. Purifying selection was noted in their evolutionary analysis that plays a crucial role in minimizing genetic diversity and maintaining the integrity of biological function. This indicates that these proteins have successfully retained their biological function and indispensability, even in the presence of the type I IFNs. The expansion of IFN-λ genes in amphibians and camels have led to the evolution of multiple IFN-λ. The CNV can arise from gene duplication and conversion events. The qPCR-based absolute quantification resulted that IFN-λ3 and IFN-λ4 have more than one copy in buffalo (Murrah) and six cattle breeds (Sahiwal, Tharparkar, Kankrej, Red Sindhi, Jersey and Holstein Friesian). Overall, these findings highlight the evolutionary diversity and functional significance of IFN-λ in
tetrapod species.