ZMYND8与NuRD复合物核心组分RBBP4相互作用界面的鉴定

Identification of the Interacting Surface Between ZMYND8 and RBBP4,a Core Components of the Nucleosome Remodeling and Deacetylase (NuRD) Complex

核小体重塑与去乙酰化酶(Nucleosome remodeling and histone deacetylase,NuRD)复合物由多个亚基组成,在转录调节和DNA损伤修复的过程中发挥着重要的功能。人源ZMYND8(Zinc finger MYND-type containing 8)能与NuRD形成复合物参与转录调节和DNA损伤修复的过程中。利用昆虫杆状病毒表达系统,经过镍柱和分子筛柱层析纯化获得电泳纯的NuRD核心亚基RBBP4蛋白质。采用等温量热滴定技术鉴定ZMYND8与RBBP4的相互作用界面,结果显示RBBP4能够结合位于ZMYND8氮端的43到54位富含碱性氨基酸残基的区域。RBBP4上的氨基酸残基点突变实验初步确定二者的相互作用界面。结合以往的研究发现,ZMYND8可以通过其氮端的碱性区域和碳端的MYND结构域环绕结合在NuRD复合物的表面。

Nucleosome remodeling and histone deacetylase(NuRD)complex contains multiple subunits and plays a critical role in transcription regulation and DNA damage repair.Human ZMYND8(Zinc finger MYND-type containing8)participates in transcription regulation and DNA damage repair by forming complex with NuRD.Rbbp4,a core submit of NuRD,was expressed in baculovirus expression system in vitro and purified by Ni-NTA column and molecular sieve chromatography column to electrophoretic purity.Isothermal titration calorimetry(ITC)experiment was used to identify the interacting surface between ZMYND8and RBBP4,and results from which demonstrated that RBBP4bound to the basic amino acids(residues43-54)at the N-terminus of ZMYND8.The site-directed mutation experiment at the amino acid residues of RBBP4further confirmed the interacting surface of both.Combined with the previous findings,it is revealed that ZMYND8binds to the surface of NuRD complex using the N-terminal basic region and C-terminal MYND domain by surrounding way.