College of Animal Science and Technology, Sichuan Agricultural University, Wenjiang, People's Republic of China; Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Wenjiang, People's Republic of China.
Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, People's Republic of China.
Zoology (Jena). 2022 Apr;151:126002. doi: 10.1016/j.zool.2022.126002. Epub 2022 Jan 10.
Translocation of RNA across the nuclear envelope relies on transport receptors. Receptor nuclear transport factor 2 (NTF2)-like export protein 1 (NXT1 [also called p15 or p15-1]) shuttles between the nucleus and cytoplasm of metazoan cells and contributes to the nuclear export of a diverse spectrum of RNAs. NXT2 (also called p15-2), a paralog of NXT1 in eutherians, also has implications for RNA nuclear export. A comprehensive description is currently lacking as to the genetic signature of these molecules. In this study, we analyzed genetic changes in the NXT1 and NXT2 genes in primates and murine rodents, including the commonly used model organisms Macaca spp., Mus musculus, and Rattus norvegicus. The results show that NXT1 has been subject to functional constraints in both phylogenetic lineages. Conversely, NXT2 exhibits discrepant patterns of genetic changes between these taxa. Murine NXT2 has evolved conservatively; by contrast, adaptive selection has frequently contributed to genetic changes in primate NXT2. The genetic discrepancy of the NXT2 orthologs leads to the suggestion that they had experienced quite different evolutionary fates potentially constituting different functional implementations in these taxa. These findings raise awareness of further study on different organisms to comprehensively understand their functional characteristics.
RNA 跨核膜的易位依赖于运输受体。核转运因子 2（NTF2）样出口蛋白 1（NXT1[也称为 p15 或 p15-1]）在真核细胞的核和细胞质之间穿梭，有助于多种 RNA 的核输出。NXT2（也称为 p15-2）是 NXT1 在真兽类动物中的同源物，也与 RNA 核输出有关。目前，这些分子的遗传特征缺乏全面的描述。在这项研究中，我们分析了灵长类动物和鼠类啮齿动物中 NXT1 和 NXT2 基因的遗传变化，包括常用的模型生物猕猴、小家鼠和褐家鼠。结果表明，NXT1 在两个进化枝中都受到功能限制。相反，NXT2 在这些类群之间表现出不同的遗传变化模式。鼠类 NXT2 进化保守；相比之下，适应性选择经常导致灵长类动物 NXT2 的遗传变化。NXT2 同源物的遗传差异表明它们经历了不同的进化命运，可能在这些类群中具有不同的功能实现。这些发现提高了对不同生物体进行进一步研究的意识，以全面了解它们的功能特征。
