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醫(yī)學論文范文:CpG甲基化調(diào)節(jié)神經(jīng)黏附分子多聚唾液酸的合成
【摘要】 目的 探討DNA甲基化是否能夠用來作為多聚唾液酸(PSA)表達的基因外調(diào)控。方法 用甲基化PCR分析成年小鼠和18d的胚胎鼠(E18)大腦不同區(qū)域合成多聚唾液酸的酶的基因- mST8SiaIV(PST)和mST8SiaII(STX)啟動子甲基化水平;用dot-blotting分析不同濃度的甲硫胺酸和丙戊酸對PSA表達的影響;用CBRA(Combined bisulfite restriction analysis)進一步確認基因- ST8SiaIV和mST8SiaII啟動子甲基化水平，神經(jīng)細胞和神經(jīng)膠質(zhì)的原代培養(yǎng)。結(jié)果 (1)胎兒鼠與小鼠的大腦、小腦、基底核和海馬，甲基化特異性的PCR結(jié)果顯示：STX基因轉(zhuǎn)錄起始區(qū)沒有甲基化，PST基因轉(zhuǎn)錄起始區(qū)在18d的胎兒鼠的所有4個區(qū)域和成年鼠的2個區(qū)域-大腦和小腦都有甲基化。(2)甲基化特異性的PCR分析原代培養(yǎng)的神經(jīng)細胞和神經(jīng)膠質(zhì)細胞STX基因未發(fā)生甲基化，但是在PST基因在神經(jīng)膠質(zhì)細胞發(fā)現(xiàn)輕微的甲基化。(3)小鼠神經(jīng)纖維母細胞瘤細胞株-Neuron2A細胞的PST基因啟動子幾乎完全被甲基化。(4)不同濃度甲硫氨酸處理Neuron2A細胞，PSA表達下降;相反丙戊酸增強了PSA的表達。結(jié)論 甲基化能夠用來作為多聚唾液酸表達的基因外調(diào)控，多聚唾液酸表達的基因外調(diào)控可能與突觸的形成和記憶的形成有關(guān)。
【關(guān)鍵詞】 多聚唾液酸;DNA甲基化;基因外調(diào)控;突觸
Polysialylation of neural cell adhesion molecule can be regulated by CpG methylation
GAO Yong-ying, CAI Hai-yan WANG Wei.(Ningxia People's Hospital, Yinchuan 750021, China)醫(yī).學全.在.線網(wǎng)站m.gydjdsj.org.cn
[Abstract] Objective To explore the methylation could be used for epigenetic regulation of PSA expression or not. Methods Methylation-specific PCR was used to analyze the promoter methylation level of mST8SiaIV (PST) and mST8SiaII (STX) which were known as enzymes to synthesize polysialic acid (PSA). Using dot-blotting to assay expression of PSA on the surface of Neuron2A treated by methionine and valproic acid at different concentration. CBRA (Combined bisulfite restriction analysis) was used to confirm the promoter methylation level of PST and STX, and primary culture of neuronal and glial cells. Results STX promoter was not methylated, but PST promoter was methylated in all four region of E18 and in two region of adult mouse brain; In primary cultured neuronal and glial cells, no methylation could be detected in STX gene, but slight methylation in PST gene in glial cells; In mouse neuroblastoma cell line, Neuro2A cells, most of the promoters of PST gene were methylated; Neuro2A cells treated by methionine or valproic acid, methionine slightly decreased the PSA expression, whereas valproic acid significantly increased. Conclusion Methylation can be utilized for epigenetic regulation of PSA expression. Epigenetic regulation of PSA may be associated with synaptic plasticity, or memory formation.
