Fantappié M R, Gimba E R, Rumjanek F D
Departamento de Bioquímica Médica ICB/CCS, Universidade Federal do Rio de Janeiro, Ilha do Fundão CEP 21941-590, Rio de Janeiro, Brazil.
Exp Parasitol. 2001 Jul;98(3):162-6. doi: 10.1006/expr.2001.4630.
Schistosoma mansoni genomic DNA from male and female adult worms was subjected to restriction by the isoschizomeric endonucleases HpaII and MspI, which display different sensitivities with respect to cytosine methylation. The digested DNA was hybridized with 13 S. mansoni probes. Southern blot analysis showed that there were no observable differences in the restriction patterns of the two isoschizomers and that the patterns were identical in male and female parasites. Adenine methylation was also ruled out since no differences were observed with DpnI, Sau3A1, or MboI restriction enzymes. The methylation-dependent restriction endonuclease McrBC, which cleaves DNA containing methylcytosine and will not cleave unmethylated DNA, did not digest S. mansoni genomic DNA. These results demonstrate that the genome of adult S. mansoni is not methylated.
来自曼氏血吸虫雌雄成虫的基因组DNA，用对胞嘧啶甲基化表现出不同敏感性的同裂酶内切核酸酶HpaII和MspI进行酶切。消化后的DNA与13个曼氏血吸虫探针杂交。Southern印迹分析表明，这两种同裂酶的酶切图谱没有可观察到的差异，并且在雌雄寄生虫中的图谱是相同的。由于用DpnI、Sau3A1或MboI限制酶未观察到差异，因此也排除了腺嘌呤甲基化。甲基化依赖性限制内切酶McrBC可切割含有甲基胞嘧啶的DNA，而不会切割未甲基化的DNA，但它并未消化曼氏血吸虫基因组DNA。这些结果表明，成年曼氏血吸虫的基因组未发生甲基化。
