title: Tetrameric ZBRK1 DNA binding domain has affinity towards cognate DNA in absence of zinc ions.
abstract: Zinc finger transcription regulatory proteins play crucial roles in cell-cycle regulation, DNA damage response and tumor genesis. Human ZBRK1 is a zinc-finger transcription repressor protein, which recognizes double helical DNA containing consensus sequences of 5'GGGXXXCAGXXXTTT3'. In the present study, we have purified recombinant DNA binding domain of ZBRK1, and studied binding with zinc ions and DNA, using biophysical techniques. The elution profile of the purified protein suggests that this ZBRK1 forms a homotetramer in solution. Dissociation and pull down assays also suggest that this domain forms a higher order oligomer. The ZBRK1-DNA binding domain acquires higher stability in the presence of zinc ions and DNA. The secondary structure of the ZBRK1-DNA complex is found to be significantly altered from the standard B-DNA conformation.
authors.affiliation: Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, Maharashtra 410 210, India.
authors.forename: Lumbini R
authors.initials: LR
authors.lastname: Yadav
authors.affiliation: Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, Maharashtra 410 210, India.
authors.forename: Mahamaya N
authors.initials: MN
authors.lastname: Biswal
authors.affiliation: Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, Maharashtra 410 210, India.
authors.lastname: Vikrant
authors.affiliation: Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, Maharashtra 410 210, India.
authors.forename: M V
authors.initials: MV
authors.lastname: Hosur
authors.affiliation: Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, Maharashtra 410 210, India. Electronic address: avarma@actrec.gov.in.
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Varma
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry*; D006801:Humans; D007477:Ions; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D004268:DNA-Binding Proteins; D007477:Ions; D012097:Repressor Proteins; C422407:ZNF350 protein, human; D004247:DNA; D015032:Zinc
keywords: Oligomer; Secondary structure; ZBRK1; Zinc-finger