Open AccessA DNA-binding protein from Ustilago maydis prefers duplex DNA without chain interruptions.
Author(s) -
James R. Rusche,
William K. Holloman
Publication year - 1983
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.3.4.605
Subject(s) - biology , ustilago , dna , hmg box , microbiology and biotechnology , plasmid , dna clamp , dna binding site , replication protein a , dna replication , pbr322 , in vitro recombination , dna binding protein , biochemistry , molecular cloning , complementary dna , rna , gene , transcription factor , promoter , reverse transcriptase , gene expression
Using a nitrocellulose filter binding assay, we have partially purified a protein from mitotic cells of Ustilago maydis that binds preferentially to covalently closed circular duplex DNA. DNA containing single- or double-strand breaks is bound poorly by the protein. Once formed, the DNA-protein complex is stable, resisting dissociation in high salt. However, when a DNA strand is broken, the complex appears to dissociate. The protein binds equally well to form I DNA of phi X174 or the plasmid pBR322, but has a higher affinity for a hybrid plasmid containing a cloned region of Drosophila melanogaster satellite DNA.