College of Biology and Food Engineering, Chongqing Three Gorges University, Chongqing, 404100, P. R. China.
College of Environmental and Chemistry Engineering, Chongqing Three Gorges University, Chongqing, 404100, P. R. China.
Sci Rep. 2018 Sep 26;8(1):14407. doi: 10.1038/s41598-018-32286-5.
As the first examination of distribution, guanine-cytosine (GC) pattern, and variation analysis of microsatellites (SSRs) in different genomic regions of six bovid species, SSRs displayed nonrandomly distribution in different regions. SSR abundances are much higher in the introns, transposable elements (TEs), and intergenic regions compared to the 3'-untranslated regions (3'UTRs), 5'UTRs and coding regions. Trinucleotide perfect SSRs (P-SSRs) were the most frequent in the coding regions, whereas, mononucleotide P-SSRs were the most in the introns, 3'UTRs, TEs, and intergenic regions. Trifold P-SSRs had more GC-contents in the 5'UTRs and coding regions than that in the introns, 3'UTRs, TEs, and intergenic regions, whereas mononucleotide P-SSRs had the least GC-contents in all genomic regions. The repeat copy numbers (RCN) of the same mono- to hexanucleotide P-SSRs showed significantly different distributions in different regions (P < 0.01). Except for the coding regions, mononucleotide P-SSRs had the most RCNs, followed by the pattern: di- > tri- > tetra- > penta- > hexanucleotide P-SSRs in the same regions. The analysis of coefficient of variability (CV) of SSRs showed that the CV variations of RCN of the same mono- to hexanucleotide SSRs were relative higher in the intronic and intergenic regions, followed by the CV variation of RCN in the TEs, and the relative lower was in the 5'UTRs, 3'UTRs, and coding regions. Wide SSR analysis of different genomic regions has helped to reveal biological significances of their distributions.
作为对六种牛科动物不同基因组区域中鸟嘌呤-胞嘧啶 (GC) 模式和微卫星 (SSR) 变异分析的首次研究,SSR 在不同区域呈非随机分布。与 3'非翻译区 (3'UTR)、5'UTR 和编码区相比,SSR 在内含子、转座元件 (TEs) 和基因间区的丰度要高得多。三核苷酸完美 SSR (P-SSR) 在编码区最为常见,而单核苷酸 P-SSR 在内含子、3'UTR、TEs 和基因间区最为常见。三核苷酸 P-SSR 在 5'UTR 和编码区的 GC 含量高于内含子、3'UTR、TEs 和基因间区,而单核苷酸 P-SSR 在所有基因组区的 GC 含量最低。相同单核苷酸至六核苷酸 P-SSR 的重复拷贝数 (RCN) 在不同区域的分布差异显著 (P<0.01)。除了编码区,单核苷酸 P-SSR 的 RCN 最多,其次是:二核苷酸>三核苷酸>四核苷酸>五核苷酸>六核苷酸 P-SSR 在相同区域。SSR 变异系数 (CV) 分析表明,相同单核苷酸至六核苷酸 SSR 的 RCN 的 CV 变化在内含子和基因间区相对较高,其次是 TEs 中 RCN 的 CV 变化,相对较低的是 5'UTR、3'UTR 和编码区。对不同基因组区域的广泛 SSR 分析有助于揭示其分布的生物学意义。