羟化酶JMJD6蛋白促进黑色素瘤转移的作用机理

JMJD6 (Jumonji domain-containing 6) is a member of the Jumonji C domain-containing family of proteins, which possesses the activity of hydroxylase, histone demethylase and dioxygenase. Compared to other members of the family, the cellular activity of JMJD6 is still not clearly defined and its biological function is still largely unexplored. It was reported that JMJD6 catalyses lysyl-hydroxylation of U2AF65, a protein associated with RNA splicing, and are involved in the splicing and transcriptional regulation of genes. This project will focus on the search for target genes for JMJD6 in melanoma cell lines A375 by RNA-seq and cluster analysis, and shed light on the mechnism of JMJD6 on angiogenesis and metastasis of melanoma by regulating the splicing and activity of some key genes in MAPK signal pathway using Northern, RNA-IP, tissue chip, in vivo imaging technology. Furthermore, our study will uncover the upstream events of JMJD6 whether and how the wild type or V600E mutant of BRAF regulates the expression of JMJD6. The future work will reveal the reason for high expression of JMJD6 in melanoma, and molecular basis for JMJD6-promoted melanoma development and progression, supporting the pursuit of JMJD6 as a potential biomarker for melanoma aggressiveness and a potential target for melanoma intervention.

JMJD6属于JMJD（JmjC domain-containing）家族中只含Jumonji C结构域的成员，它兼具羟化酶、去甲基化酶及双加氧酶多种酶活性。前期的研究表明JMJD6是参与RNA剪切相关蛋白U2AF65的羟化酶，调控一系列基因的剪接与转录。本项目将通过转录组测序、聚类分析等筛选JMJD6在黑色素瘤A375细胞系中调控的靶基因，继而利用RNA印迹、RNA免疫共沉淀、组织芯片、动物活体成像等方法从分子、细胞及动物水平探究JMJD6影响MAPK信号通路中关键基因可变剪接及活性继而促进黑色素瘤转移及血管生成的作用机理。另外，我们还将探讨在黑色素瘤中高频突变的BRAF蛋白其野生型或V600E突变型对JMJD6的转录调控，揭示JMJD6的上游事件。本研究将回答在黑色素瘤中JMJD6蛋白水平高表达的原因以及JMJD6促进黑色素瘤发生发展的分子基础，有望为黑色素瘤的早期诊断提供新的生化指标

受资助人围绕基因转录的表观遗传调控和蛋白质的翻译后修饰两方面，对肿瘤发生发展的机理进行了原创研究，在本基金资助期间，以通讯/共同通讯在Nature Communication、Cell Research、Nucleic Acids Research、Molecular Cancer杂志发表文章4篇，平均影响因子12.15。系列研究鉴定了在肿瘤转移及耐药中起重要作用的转录因子及表观遗传修饰酶，揭示了重要的抗癌药物靶点表皮生长因子受体EGFR的调控机制，鉴定了影响基因转录和基因组稳定性的组蛋白去泛素化酶，为肿瘤发生发展的分子基础和新药设计提供了新的证据。申请人作为第四完成人2016年获国家自然科学二等奖。