Duan Yuange, Chen Shuxian, Cai Wanzhi, Song Wen, Li Hu
Department of Entomology and State Key Laboratory of Agricultural and Forestry Biosecurity, MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
NAR Genom Bioinform. 2025 Jul 11;7(3):lqaf096. doi: 10.1093/nargab/lqaf096. eCollection 2025 Sep.
The genetic information flows from DNA to RNA to protein with high fidelity. While highly essential or conserved genomic sequences are often thought to be compensated by post-transcriptional mechanisms such as alternative splicing (AS) and RNA editing to enhance molecular diversity, this pattern does not necessarily hold true across all genomic regions. Signal peptides are short N-terminal sequences that direct the localization of proteins. By analyzing the genomes and transcriptomes of and several other commonly studied species, we observed a consistent pattern that genes encoding signal peptides tend to produce fewer protein isoforms than those without. Moreover, AS events at the N-terminal region are significantly underrepresented in signal peptide-containing genes. In both fruitfly and human, RNA recoding events are notably avoided in signal peptide regions. These observations suggest that the presence of signal peptides imposes constraints on both genomic evolution and transcriptomic diversity. Our results provide new insight into the relationship between genome conservation and post-transcriptional regulation, showing that conserved genomic elements, such as signal peptides, do not necessarily coincide with increased post-transcriptional diversification. This study advances our understanding of the evolutionary principles governing RNA-based regulatory mechanisms.
遗传信息以高保真度从DNA流向RNA再流向蛋白质。虽然人们通常认为高度必需或保守的基因组序列会通过诸如可变剪接（AS）和RNA编辑等转录后机制得到补偿，以增强分子多样性，但这种模式并不一定适用于所有基因组区域。信号肽是指导蛋白质定位的短N端序列。通过分析[具体物种]和其他几个常用研究物种的基因组和转录组，我们观察到一种一致的模式：编码信号肽的基因往往比不编码信号肽的基因产生的蛋白质异构体更少。此外，含信号肽基因的N端区域的可变剪接事件明显较少。在果蝇和人类中，信号肽区域都明显避免了RNA编码事件。这些观察结果表明，信号肽的存在对基因组进化和转录组多样性都施加了限制。我们的结果为基因组保守性与转录后调控之间的关系提供了新的见解，表明保守的基因组元件，如信号肽，不一定与转录后多样化的增加相一致。这项研究推进了我们对基于RNA的调控机制的进化原理的理解。
