The research for the amplification of stress response by modification of the nucleosomal conformation

新型组蛋白去乙酰化酶抑制剂（HDACIs） CHAP31和FR901228可使腺病毒介导的β-半乳糖苷酶在培养细胞中的表达提高10倍以上。类似的增强效应不仅存在于报告基因AdLacZ中，也存在于腺病毒介导的热休克蛋白72 （HSP72）功能基因中。转基因扩增与核心组蛋白的乙酰化状态密切相关，而与柯萨奇和腺病毒受体（CAR）的过表达无关。这表明，被认为与内源性基因表达有关的组蛋白乙酰化也与转基因表达有关。hdac对热疗诱导的内源性HSP72表达没有扩增作用，提示hdac对基因表达的增强作用在转导基因中具有特异性。CHAP31和FR901228增强了腺病毒介导的小鼠肝脏β-半乳糖苷酶的表达。曲古菌素A （trichostatin A， TSA）是一种文献充分的经典HDACI，但在体内模型中未见报道。CHAP31和FR901228比TSA稳定得多，它们的稳定性被认为是在体内模型中起作用的原因。此外，类似的增强作用不仅在肝脏，而且在肾、肺和心脏也被观察到，尽管对这三个器官的转导效果远低于肝脏。目前我们正在进行HSP72转导对肝脏缺血再灌注损伤影响的实验。当载体剂量增加以达到充分的转基因表达时，腺病毒载体的肝毒性变得显著，这是一个两难的问题。在那里。期望新型HDACIs与腺病毒载体联合给药可以减少载体剂量，并可能导致利用腺病毒载体进行基因治疗的突破。

Novel histone deacetylase inhibitors (HDACIs) CHAP31 and FR901228 could enhance adenovirus-mediated β-galactosidase expression more than ten times in cultured cells. Similar augmentative effects were observed not only in AdLacZ, a reporter gene, but also in adenovirus-mediated heat shock protein 72 (HSP72), a functional gene. Amplification of the transgene expression was strongly related to the acetylation state of core histones, not to the over-expression of coxsackie and adenovirus receptor (CAR). It was suggested that histone acetylation, which had been thought to be connected with endogenous gene expression, was also related to transgene expression.HDACIs did not amplify endogenous HSP72 expression induced by hyperthermia, suggesting that the augmentative effect on gene expression by HDACIs was specific in transduced genes.CHAP31 and FR901228 enhanced adenovirus-mediated β-galactosidase expression in mice liver. It has not been reported that trichostatin A (TSA), a well-documented classical HDACI, enhanced transgene expression in in vivo model. CHAP31 and FR901228 are much more stable than TSA, and their stability was thought to contribute to the effect in in vivo model. Furthermore, similar augmentative effects were observed not only in the liver, but also in the kidney, lung, and heart although transduction efficacy to the three organs were much lower than the liver.Now we are conducting the experiment about the effect of HSP72 transduction on ischemia-reperfusion injury of the liver. There is a dilemma that hepatic toxicity of adenovirus vector becomes remarkable when the vector dose is raised to achieve sufficient transgene expression. There. is an expectation that co-administration of the novel HDACIs with adenovirus vector can reduce the vector dose and may lead to a breakthrough in the gene therapy using adenovirus vector.