人源锌指蛋白ZNF24及其锌指结构域的表达、纯化及DNA结合性质的研究  

Expression, Purification and Analysis of DNA Binding Properties of Human Zinc Finger Transcription Factor ZNF24 and Its Zinc Finger Domain

作　　者：苏晓琴 高宝才 纪锐[1] 王森 李继喜[1] SU Xiaoqin;GAO Baocai;JI Rui;WANG Sen;LI Jixi(School of Life Sciences,Fudan University,Shanghai 200438,China)

机构地区：[1]复旦大学生命科学学院,上海200438

出　　处：《复旦学报（自然科学版）》2022年第2期167-174,共8页Journal of Fudan University：Natural Science

基　　金：国家重点研发计划“蛋白质机器与生命过程调控”重点专项(2016YFA0500600)。

摘　　要：转录因子是调控基因表达的关键蛋白,能够以序列特异性方式结合DNA。ZNF24是Krüppel-like锌指转录因子家族成员之一,在细胞增殖和分化中起重要作用,能促进肝癌细胞的增殖,抑制神经元细胞的分化。ZNF24蛋白N端包含一个SCAN结构域,C端为锌指区,由4个串联的C2H2型锌指结构组成。ZNF24能特异性识别和结合基因的启动子,参与基因的表达调控,但其发挥功能的具体分子机制并不清楚。本文我们在大肠杆菌中成功表达了人源锌指蛋白ZNF24全长和其锌指结构域ZNF24(243~368),ZNF24全长蛋白在溶液中以三聚体形式存在,而锌指结构域在溶液中为单体,表明ZNF24蛋白N端的SCAN结构域能够促进全长蛋白的寡聚化。凝胶迁移实验验证ZNF24全长蛋白和锌指结构域与双链DNA底物结合能力,为进一步研究锌指蛋白ZNF24调控基因表达提供理论基础,相关结果表明SCAN结构域介导的蛋白寡聚可能代表了一种新的转录活性调节机制。Transcription factors are key proteins that regulate gene expression and can bind to DNA in a sequence-specific manner. ZNF24 is a member of the Krüppel-like zinc finger transcription factor family, which plays an important role in cell proliferation and differentiation. It can promote the proliferation of liver cancer cells and inhibit the differentiation of neurons. The N-terminal region of ZNF24 protein contains a SCAN domain and the C-terminus is zinc finger region, which is composed of four C2 H2 zinc finger motif. ZNF24 can specifically recognize and bind to the gene promoter and participate in the regulation of gene expression, but the detailed molecular mechanism of its function is not clear. In this study, we successfully expressed human ZNF24 and its zinc finger domain ZNF24(243—368) in E. coli. We found that ZNF24 protein exists as a trimer in solution, while its zinc finger domain is a monomer, indicating that the N-terminal SCAN domain of ZNF24 may promote the oligomerization of full-length protein. The binding ability of zinc finger domain and full-length ZNF24 protein to double-stranded DNA substrate was verified by EMSA experiment, which provides a basis for further study of ZNF24 regulating gene expression, and also suggests that SCAN domain-mediated protein oligomerization may represent a new mechanism of transcriptional activity regulation.

关 键 词：锌指蛋白 ZNF24 SCAN结构域 蛋白纯化 DNA结合 

分 类 号：Q78[生物学—分子生物学]