Moon Eun-Kyung, Hong Yeonchul, Lee Hae-Ahm, Quan Fu-Shi, Kong Hyun-Hee
Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea.
Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu 41944, Korea.
Korean J Parasitol. 2017 Apr;55(2):115-120. doi: 10.3347/kjp.2017.55.2.115. Epub 2017 Apr 30.
Encystation mediating cyst specific cysteine proteinase (CSCP) of is expressed remarkably during encystation. However, the molecular mechanism involved in the regulation of CSCP gene expression remains unclear. In this study, we focused on epigenetic regulation of gene expression during encystation of . To evaluate methylation as a potential mechanism involved in the regulation of CSCP expression, we first investigated the correlation between promoter methylation status of CSCP gene and its expression. A 2,878 bp of promoter sequence of CSCP gene was amplified by PCR. Three CpG islands (island 1-3) were detected in this sequence using bioinformatics tools. Methylation of CpG island in trophozoites and cysts was measured by bisulfite sequence PCR. CSCP promoter methylation of CpG island 1 (1,633 bp) was found in 8.2% of trophozoites and 7.3% of cysts. Methylation of CpG island 2 (625 bp) was observed in 4.2% of trophozoites and 5.8% of cysts. Methylation of CpG island 3 (367 bp) in trophozoites and cysts was both 3.6%. These results suggest that DNA methylation system is present in CSCP gene expression of . In addition, the expression of encystation mediating CSCP is correlated with promoter CpG island 1 hypomethylation.
包囊化介导的特定于包囊的半胱氨酸蛋白酶（CSCP）在包囊化过程中显著表达。然而，CSCP基因表达调控所涉及的分子机制仍不清楚。在本研究中，我们聚焦于包囊化过程中基因表达的表观遗传调控。为了评估甲基化作为参与CSCP表达调控的潜在机制，我们首先研究了CSCP基因启动子甲基化状态与其表达之间的相关性。通过PCR扩增了CSCP基因2878 bp的启动子序列。使用生物信息学工具在该序列中检测到三个CpG岛（岛1 - 3）。通过亚硫酸氢盐序列PCR测定滋养体和包囊中CpG岛的甲基化情况。在8.2%的滋养体和7.3%的包囊中发现了CpG岛1（1633 bp）的CSCP启动子甲基化。在4.2%的滋养体和5.8%的包囊中观察到了CpG岛2（625 bp）的甲基化。滋养体和包囊中CpG岛3（367 bp）的甲基化率均为3.6%。这些结果表明，DNA甲基化系统存在于CSCP基因表达过程中。此外，介导包囊化的CSCP的表达与启动子CpG岛1的低甲基化相关。
