Rao Deviyani M, Horton Emma R, Barrington Chloe L, Briney Chloe A, Henriksen Jesslyn C, Martinez-Seidel Federico, Morrison Evan J, Sterling Erica M, Provencio Edgar D, Harris Mia, Allen Emily, Hesselberth Jay R, Rissland Olivia S
Department of Biochemistry & Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA; RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA.
Department of Biochemistry & Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA; RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA.
Cell Rep. 2025 Jul 22;44(7):115822. doi: 10.1016/j.celrep.2025.115822. Epub 2025 Jun 18.
2A peptides are 18- to 22-amino-acid sequences that cause an unusual co-translational peptide-bond-skipping event. Initially discovered in viruses, they allow multiple proteins to be produced from a single open reading frame. Despite their utility, their evolutionary prevalence and sequence diversity remain unclear. Our computational analyses predict ∼2,200 2A peptides, significantly expanding the known class of 2A peptides (class A) and identifying a previously unrecognized class (class B). Predicted 2A peptides are widespread in RNA viruses and eukaryotes. Functional tests in human cells confirm skipping activity in most cases, suggesting that thousands of active 2A peptides exist. Mutational analysis reveals key residues near the skipped bond and within the upstream region; for instance, class B 2A peptides contain a conserved N-terminal tryptophan, whose register and identity are critical for activity. Together, our findings reveal that 2A peptides are more diverse and widespread than previously appreciated.
2A肽是由18至22个氨基酸组成的序列，可引发一种不同寻常的共翻译肽键跳跃事件。最初在病毒中发现，它们能使单个开放阅读框产生多种蛋白质。尽管其具有实用性，但其进化普遍性和序列多样性仍不清楚。我们的计算分析预测约有2200种2A肽，显著扩展了已知的2A肽类别（A类），并鉴定出一个先前未被识别的类别（B类）。预测的2A肽广泛存在于RNA病毒和真核生物中。在人类细胞中的功能测试证实了大多数情况下的跳跃活性，表明存在数千种活性2A肽。突变分析揭示了跳跃键附近和上游区域的关键残基；例如，B类2A肽含有一个保守的N端色氨酸，其排列和特性对活性至关重要。总之，我们的研究结果表明，2A肽比以前认为的更加多样和广泛。
