Study On The DNA-binding Properties Of Zinc Finger Protein 191

As an important class of transcription factors in eukaryote, zinc-finger proteins play very important roles in the regulation of gene expression, signal transduction, cell growth, differentiation and development by binding to their DNA recognition sites. Studies on the DNA binding properties of zinc finger proteins are important for searching for the downstream genes regulated by them. Here we report the DNA binding property of a Cys2His2 type transcription factor Zinc finger protein 191 (Zfp191) which has been newly found to be significant in mice.Based on studies at present, it is known that Zinc finger protein 191(Zfp191), which is widely expressed in multiple tissues and organs of mice, was supposed to be developmentally regulated and related to cartilage differentiation and basic cellular processes. It is more notable that the phenotype represented in the Zfp191 gene knockout mice indicates Zfp191's irreplaceable role in early embryonic development. However, the exact role of Zfp191 in development has not been known. So it is necessary to ascertain its DNA binding properties and investigate how Zfp191 works in developmental regulation by regulating the expression of its downstream genes.In our studies, We have designed and constructed a fusion protein in which the N terminal part of Zfp191 was substituted by the GST sequence. Then target DNA was characterized by determining the binding specificity and dependence on zinc using magnetic nanoparticles binding assay, DNA microarrays and microwell colorimetric assay. The data shows that the DNA binding domain of Zfp191 can specifically bind to the TCAT repeat motif, and there is cooperative effect among the multiple binding sites on the target DNA. Furthermore, zinc-dependency of the binding reaction was also given experimental proof in our work. This work provides a foundation for further studies on the role of Zfp191 in gene regulation and development.