Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada.
Institute for Comparative Genomics, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada.
Proc Natl Acad Sci U S A. 2023 Dec 5;120(49):e2306381120. doi: 10.1073/pnas.2306381120. Epub 2023 Nov 29.
Inteins are self-splicing protein elements found in viruses and all three domains of life. How the DNA encoding these selfish elements spreads within and between genomes is poorly understood, particularly in eukaryotes where inteins are scarce. Here, we show that the nuclear genomes of three strains of encode between 45 and 103 inteins, in stark contrast to four found in the most intein-rich eukaryotic genome described previously. The inteins reside in a wide range of proteins, only some of which correspond to intein-containing proteins in other eukaryotes, prokaryotes, and viruses. Our data also suggest that viruses have contributed to the spread of inteins in and the colonization of new alleles. The persistence of inteins might be partly explained by intragenomic movement of intein-encoding regions from gene to gene. Our intein dataset greatly expands the spectrum of intein-containing proteins and provides insights into the evolution of inteins in eukaryotes.
内肽是在病毒和所有三个生命领域中发现的自我剪接蛋白元件。这些自私元件的 DNA 如何在基因组内和基因组之间传播，人们知之甚少，特别是在内共生体中，内共生体很少见。在这里，我们表明，三种 菌株的核基因组编码了 45 到 103 个内肽，这与之前描述的最富含内肽的真核生物基因组中发现的四个内肽形成鲜明对比。这些内肽存在于多种蛋白质中，其中只有一些与其他真核生物、原核生物和病毒中含内肽的蛋白质相对应。我们的数据还表明，病毒可能有助于内肽在 和新等位基因中的传播。内肽的持续存在部分可以通过基因间基因内编码区域的移动来解释。我们的内肽数据集极大地扩展了含内肽蛋白的范围，并为真核生物中内肽的进化提供了新的见解。
