發(fā)布時間：2018-04-18 22:09

  本文選題：組蛋白去甲基化 + LSD1��； 參考：《華東師范大學》2010年碩士論文

【摘要】：組蛋白N末端的各種轉(zhuǎn)錄后共價修飾可影響染色體的結(jié)構(gòu)和調(diào)控基因的轉(zhuǎn)錄,組蛋白的甲基化修飾就是其中一種。胺基氧化酶家族的組蛋白去甲基化酶LSD1和JmjC家族的組蛋白去甲基化酶JMJD1A都參與雄性激素受體調(diào)控的轉(zhuǎn)錄激活過程,而且它們的異常表達與前列腺癌的發(fā)生發(fā)展相關(guān),但對其分子機制的了解卻很少。我們用慢病毒載體分別將去甲基化酶LSD1和JMJD1A兩種蛋白的shRNA質(zhì)粒轉(zhuǎn)入前列腺癌LNCaP細胞中,得到穩(wěn)定降低LSD1或JMJD1A表達的細胞系。然后我們通過用反轉(zhuǎn)錄聚合酶鏈反應實驗和染色體免疫共沉淀實驗發(fā)現(xiàn),降低LSD1或JMJD1A的表達,都能在一定程度上抑制雄性激素調(diào)控的下游基因(例如PSA和NKX3.1)的表達,而且在雄性激素依賴的轉(zhuǎn)錄激活過程中,降低LSD1或JMJD1A的表達不影響染色體重塑的發(fā)生、組蛋白H3的乙�；揎椝胶虷3K4me2修飾水平的增高；同時對雄性激素受體與其靶基因上游的雄性激素受體應答元件的識別和結(jié)合、雄性激素受體對RNA聚合酶Ⅱ、以及共激活因子SRC家族(SRC-1, SRC-3)和CBP等的招募也沒有很明顯的影響。而且與以前的報道一致的是,降低JMJD1A和LSD1的表達使組蛋白H3K9me2修飾增高。更有趣的是,降低LSD1的表達可抑制了雄性激素受體對介質(zhì)蛋白TRAP220在轉(zhuǎn)錄激活過程中的招募,而降低JMJD1A的表達卻沒有這樣的現(xiàn)象。我們的結(jié)果表明同為組蛋白H3K9me/H3K9me2位的去甲基化酶JMJD1A和LSD1的調(diào)控機制存在一定差異,而且LSD1可能還通過控制對介質(zhì)蛋白的招募而參與調(diào)控雄性激素誘導的轉(zhuǎn)錄激活過程。
[Abstract]:Various post-transcriptional modifications of histone N-terminal can affect the structure of chromosomes and the transcription of regulatory genes. Histone methylation is one of them.The histone demethylase (LSD1) of the amine oxidase family and the histone demethylase (JMJD1A) of the JmjC family are involved in the transcriptional activation of androgen receptor regulation, and their abnormal expression is related to the occurrence and development of prostate cancer.But little is known about its molecular mechanism.The shRNA plasmids of demethylase LSD1 and JMJD1A were transferred into LNCaP cells of prostate cancer with lentivirus vectors, respectively, to obtain a cell line that stably reduced the expression of LSD1 or JMJD1A.Then, by reverse transcriptase polymerase chain reaction and chromosome immunoprecipitation, we found that lowering the expression of LSD1 or JMJD1A could inhibit the expression of downstream genes (such as PSA and NKX3.1) regulated by androgen to some extent.In the course of androgen dependent transcriptional activation, the decrease of LSD1 or JMJD1A expression did not affect the occurrence of chromosome remodeling, and the acetylation modification level of histone H3 and the increase of H3K4me2 modification level were observed.At the same time, the recognition and binding of the male hormone receptor to the response element of the male hormone receptor upstream of the target gene was not obvious. The male hormone receptor had no significant effect on the recruitment of RNA polymerase 鈪，

本文編號：1770283