本研究利用已公布的二斑叶螨Tetranychusurticae和肩突硬蜱Ixodesscapularis的全基因组测序结果,对其基因组中的微卫星序列进行了系统分析和比较。结果表明:在二斑叶螨基因组中共找到微卫星7934个,出现频率为1/11.45kb,占全基因组碱基总数的0.16%,其中三碱基重复微卫星最多,占总数的72.83%;在肩突硬蜱基因组中共找到550629个微卫星,出现频率为1/3.21kb,占全基因组碱基总数的0.57%,其中单碱基重复微卫星最多,占总数的73.74%。另外,肩突硬蜱基因组中微卫星的重复次数普遍高于二斑叶螨基因组中微卫星的重复次数,二斑叶螨基因组中微卫星的GC含量(34.10%)明显高于肩突硬蜱(24.35%)。微卫星家族方面,二斑叶螨基因组倾向拥有更多的唯一序列(P〈0.0001)。A、T、AG、TC、TG、GAT、ATTT、AATA是两个物种共有的常见核心重复序列。
The sequences of microsatellites in Tetranychus urticae and lxodes scapularis genomes were compared in this study. A total of 7934 microsatellites were observed in T. urticae genome. The frequency was 1/11.45 kb and covering about 0.16% of the genome. Trinucleotide repeat motifs (72.83%) appeared to be the most abundant type in T. urticae genome. However, 550 629 microsatellites were observed in I. scapularis genome. The frequency was 1/3.21 kb and covering about 0.57% of the genome. The mononucleotide microsatellite was the most abundant type in I. scapularis genome and accounted for 73.74% of the total. The microsatellites in I. scapularis genome had more repeats than in T. urticae. What's more, the microsatellites in T. urticae genome had a higher GC content (34.10%) than in I. scapularis (24. 35% ). The genome of T. urticae contained a higher proportion of unique microsatellite sequences than I. scapularis. Repeats of A, T, AG, TC, TG, GAT, ATTT and AATA were the common core sequences in the two genomes.