普通刺参(Apostichopus japonicus)和白刺参不同组织基因组DNA的MSAP研究

MSAP Analysis of Genomic DNA in the Tissues of Apostichopus japonicus and White A. japonicus

中文关键词: 刺参；MSAP  CCGG位点；甲基化水平

英文关键词: Apostichopus japonicus  Methylation-sensitive amplification polymorphism (MSAP)  CCGG sites  Methylation level

中文摘要:

      本研究分别以普通刺参(Apostichopus japonicus)和白刺参基因组DNA为实验材料，应用甲基化敏感扩增多态性(Methylation-sensitive amplified polymorphism, MSAP)技术对刺参体壁、呼吸树和消化道3个组织的DNA甲基化水平和甲基化模式进行了研究，初步探讨了DNA甲基化对刺参组织间基因特异性表达的影响。结果显示，筛选得到的9对引物组合能够在普通刺参和白刺参两个群体中得到稳定扩增，在两群体刺参中分别检测到5932和5208个位点，均以未甲基化位点为主，普通刺参和白刺参未甲基化位点数分别为4317和3944，分别占总扩增条带数的72.78%和75.73%。普通刺参体壁的甲基化水平为31.07%，呼吸树为23.36%，消化道为26.34%；白刺参中体壁的甲基化水平为29.88%，呼吸树为23.25%，消化道为19.45%，由此可见，体壁的甲基化率在两群体中是最高的。普通刺参和白刺参同一组织间的甲基化水平和甲基化模式不同，同一群体体壁、呼吸树和消化道不同组织间的甲基化水平和模式也不同。甲基化在普通刺参和白刺参组织分化和发育过程中可能发挥着十分重要的作用。在检测的3个组织中，CCGG序列的全甲基化位点较半甲基化位点多。

英文摘要:

      DNA methylation was one of key epigenetic modifications in eukaryotes genomes, and has been extensively studied in the field of fishery in recent years. Here we applied MSAP (Methylation-sensitive amplified polymorphism) and analyzed the level and pattern of methylation of genomic DNA in the body wall, the respiratory tree, and the digestive tract of Apostichopus japonicus and white A. japonicus. We also compared the effects of DNA methylation in specific gene expression in different tissues of A. japonicus and white A. japonicus. In this study, a combination of 9 pairs of primers was used for the amplification of stable and clear fragments of the two populations. A total of 5932 and 5208 sites were detected in normal A. japonicus and white A. japonicus respectively, and they were mainly located at the unmethylated CCGG sites. There were 4317 and 3944 unmethylated sites in normal A. japonicus andwhite A. japonicus populations, accounting for 72.78% and 75.73% respectively. The methylation rates in the body wall, respiratory tree, and digestive tract of normal A. japonicus were about 31.07%, 23.36%, and 26.34% respectively, and those in A. japonicus were 29.88%, 23.25%, and 19.45%. These results suggested that the methylation rate in the body wall was the highest in both populations. It was inferred that the degree and pattern in DNA methylation could be different at both tissues and populations. DNA methylation may play an important role in the process of tissue differentiation and development in normal A. japonicus and white A. japonicus. Fully-methylated sites outnumbered hemi-methylated sites in the three tissues of both populations. This study provided better understanding of distinct levels and patterns of genome DNA methylation in different tissues and populations. Our findings also shed light on the relationship between the DNA methylation and the albino body wall of white A. japonicus