Dvorak Pavel, Hanicinec Vojtech, Soucek Pavel
Department of Biology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia.
Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia.
Front Genet. 2023 Jan 10;13:1085139. doi: 10.3389/fgene.2022.1085139. eCollection 2022.
The evidence that introns can influence different levels of transfer of genetic information between DNA and the final product is increasing. Longer first introns were found to be a general property of eukaryotic gene structure and shown to contain a higher fraction of conserved sequence and different functional elements. Our work brings more precise information about the position of the longest introns in human protein-coding genes and possible connection with biological function and gene expression. According to our results, the position of the longest intron can be localized to the first third of introns in 64%, the second third in 19%, and the third in 17%, with notable peaks at the middle and last introns of approximately 5% and 6%, respectively. The median lengths of the longest introns decrease with increasing distance from the start of the gene from approximately 15,000 to 5,000 bp. We have shown that the position of the longest intron is in some cases linked to the biological function of the given gene. For example, DNA repair genes have the longest intron more often in the second or third. In the distribution of gene expression according to the position of the longest intron, tissue-specific profiles can be traced with the highest expression usually at the absolute positions of intron 1 and 2. In this work, we present arguments supporting the hypothesis that the position of the longest intron in a gene is another biological factor modulating the transmission of genetic information. The position of the longest intron is related to biological functions in some human genes.
内含子能够影响遗传信息在DNA与最终产物之间不同水平传递的证据越来越多。人们发现较长的首个内含子是真核基因结构的一个普遍特征，并显示其含有更高比例的保守序列和不同的功能元件。我们的工作带来了关于人类蛋白质编码基因中最长内含子位置的更精确信息，以及其与生物学功能和基因表达之间可能的联系。根据我们的结果，最长内含子的位置可定位于64%的内含子的前三分之一处、19%的内含子的中间三分之一处以及17%的内含子的后三分之一处，在中间和最后的内含子处有明显的峰值，分别约为5%和6%。最长内含子的中位数长度随着与基因起始位置距离的增加而从约15,000 bp降至5,000 bp。我们已经表明，最长内含子的位置在某些情况下与给定基因的生物学功能相关。例如，DNA修复基因的最长内含子更常位于第二个或第三个位置。在根据最长内含子位置进行的基因表达分布中，可以追踪到组织特异性图谱，通常在内含子1和2的绝对位置处表达最高。在这项工作中，我们提出了支持以下假设的论据：基因中最长内含子的位置是调节遗传信息传递的另一个生物学因素。最长内含子的位置与一些人类基因的生物学功能相关。
