摘要
DNA甲基转移酶(DNA methyltransferase,DNMT)是表观遗传学研究热点.本文分析DNMT1、DNMT2、DNMT3A、DNMT3B、DNMT3L在成人胃粘膜的表达,并初步研究DNMT抑制剂对胃粘膜细胞的影响.免疫组织化学法对60例成人胃粘膜组织分析发现,5种DNMT均在组织中表达,以DNMT2、DNMT3B表达率较高,DNMT3L、DNMT3A次之,DNMT1较低.进一步分析发现,幽门螺杆菌感染与非感染的胃粘膜组织有DNMT表达差异,以感染组中DNMT1、DNMT2、DNMT3B表达增强较显著.免疫荧光法及Western免疫印迹法对胃粘膜细胞株GES-1分析发现,5种DNMT亦在细胞中表达;且DNMT1为胞核胞浆共表达,DNMT2为胞核表达,DNMT3A、DNMT3B、DNMT3L为胞浆表达.噻唑蓝比色法研究GES-1发现,DNMT抑制剂5-氮杂-2'-脱氧胞苷可抑制GES-1增殖,并呈时间剂量依赖.研究提示,DNMT在成人胃粘膜表达并发挥作用,幽门螺旋杆菌感染可能与DNMT表达异常相关.
DNA methyltransferase(DNMT)was the research focus of epigenetics.Here we investigated protein expressions of DNMT1,DNMT2,DNMT3A,DNMT3B,DNMT3L in adult gastric mucosa and studied the effect of DNMT inhibitor(5-Aza-2′-dC) on GES-1(gastric mucosa cell line).Immunohistochemistry was implemented on 60 samples of adult gastric mucosa tissues.We found that five kinds of DNMT proteins all existed in gastric tissues,and the positive expression rates of DNMT2,DNMT3B were higher than those of other DNMT.There were also differential expressions of DNMT1,DNMT2 and DNMT3B between gastric tissues with Helicobacter pylori infection and those without H.pylori infection,and the expression rates of infected group were higher than those of non-infected group(P0.05).Immunofluorescence and Western blotting were used on GES-1.The results showed that DNMT proteins were expressed in gastric mucosa cell line.And DNMT1 were distributed in nucleus and cytoplasm.DNMT2 was distributed in nucleus.DNMT3A,DNMT3B,DNMT3L were distributed in cytoplasm.MTT assay was carried on for GES-1 with DNMT inhibitor(5-Aza-2′-deoxycytidine).We found that 5-Aza-2,-deoxycytidine had anti-proliferative effect on GES-1 in a dose-and time-dependent manner.These results suggested that DNMT proteins were expressed in adult gastric mucosa.DNMT played a role as proliferation regulator more or less in gastric mucosa cell.Abnormal expressions of DNMT1,DNMT2 and DNMT3B may be correlated with H.pylori infection in gastric mucosa tissue.
出处
《中国生物化学与分子生物学报》
CAS
CSCD
北大核心
2011年第11期1032-1038,共7页
Chinese Journal of Biochemistry and Molecular Biology