Open AccessIsolation of Drosophila proteins that bind selectively to left-handed Z-DNA.
Author(s) -
Alfred Nordheim,
Paul Tesser,
Fernando Azorı́n,
Young H. Kwon,
Achim Möller,
Alexander Rich
Publication year - 1982
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.79.24.7729
Subject(s) - dna , plasmid , oligonucleotide , escherichia coli , microbiology and biotechnology , dna binding protein , biology , sephadex , affinity chromatography , biochemistry , dna supercoil , recombinant dna , chemistry , dna replication , gene , transcription factor , enzyme
An affinity column for isolating Z-DNA binding proteins was made by attaching brominated poly(dG-dC) to Sephadex. Proteins from Drosophila nuclei were prepared and those that could bind to Escherichia coli B-DNA were removed from the solution. The remaining proteins were passed over the Z-DNA affinity column and then eluted with NaCl. Using both direct and competitive filter binding assays, we found that the eluted proteins bind to brominated poly(dG-dC) (Z-DNA) and poly(dG-m5dC) but not to poly(dG-dC) (B-DNA), native or denatured E. coli or calf thymus DNA, or brominated oligonucleotides. The proteins also bind to negatively supercoiled plasmids carrying Z-DNA sequences but not to relaxed or linearized plasmids in which the Z-DNA conformation is no longer present. Gel analysis reveals a mixture of several large proteins up to approximately 150,000 daltons.