Competence Center for Mathematical and Algorithmical Methods in Biology, Biotechnology and Medicine, Mannheim University of Applied Sciences, 68163 Mannheim, Germany.
J Theor Biol. 2021 Aug 21;523:110708. doi: 10.1016/j.jtbi.2021.110708. Epub 2021 Apr 20.
Protein synthesis is a crucial process in any cell. Translation, in which mRNA is translated into proteins, can lead to several errors, notably frame shifts where the ribosome accidentally skips or re-reads one or more nucleotides. So-called circular codes are capable of discovering frame shifts and their codons can be found disproportionately often in coding sequences. Here, we analyzed motifs of circular codes, i.e. sequences only containing codons of circular codes, in biological and artificial sequences. The lengths of these motifs were compared to a statistical model in order to elucidate if coding sequences contain significantly longer motifs than non-coding sequences. Our findings show that coding sequences indeed show on average greater motif lengths than expected by chance. On the other hand, the motifs are too short for a possible frame shift recognition to take place within an entire coding sequence. This suggests that as much as circular codes might have been used in ancient life forms in order to prevent frame shift errors, it remains to be seen whether they are still functional in current organisms.
蛋白质合成是任何细胞中的一个关键过程。翻译过程中，mRNA 被翻译成蛋白质，可能会导致几种错误，特别是核糖体意外跳过或重新读取一个或多个核苷酸的框移。所谓的圆形密码子能够发现框移，并且它们的密码子在编码序列中不成比例地频繁出现。在这里，我们分析了圆形密码子的模体，即仅包含圆形密码子的序列，在生物和人工序列中。这些模体的长度与统计模型进行了比较，以阐明编码序列是否比非编码序列包含更长的模体。我们的研究结果表明，编码序列确实显示出比随机预期更长的模体长度。另一方面，这些模体太短，无法在整个编码序列中发生可能的框移识别。这表明，尽管圆形密码子在古代生命形式中可能被用于防止框移错误，但它们在当前生物体内是否仍然具有功能还有待观察。
