Composition and DNA-binding properties of the nuclear matrix proteins from mammalian cell nuclei.
A rapidly sedimenting DNA-protein complex was isolated from nuclear lysates in 2 M NaCl and characterized with regard to its polypeptide composition and the DNA-binding properties of the purified proteins. The complex consists of the nuclear matrix with attached DNA. Electrophoresis in SDS-polyacrylamide gels revealed two major and five minor polypeptide bands, mainly in the 60 to 75 kDa molecular weight region. The DNA-matrix complex dissociated into free DNA and proteins in the presence of 2 M NaCl and 5 M urea. The proteins could be purified by chromatography on hydroxyapatite and showed a strong tendency to reassociate at 0.15 M NaCl concentration in the absence of urea. DNA was bound to the reassociated proteins at 0.15 M NaCl concentration. Part of the DNA-protein complex was stable at 1 M NaCl concentration. The binding appeared to be random with regard to the DNA sequence.
D000818:Animals; D002352:Carrier Proteins / Q000302:isolation & purification*; D002417:Cattle; D002467:Cell Nucleus / Q000032:analysis*; D002478:Cells, Cultured; D004268:DNA-Binding Proteins; D003851:Deoxyribonucleases; D003852:Deoxyribonucleoproteins / Q000302:isolation & purification*; D007700:Kinetics; D008099:Liver / Q000032:analysis*; D008970:Molecular Weight; D009695:Nucleic Acid Renaturation; D009698:Nucleoproteins / Q000302:isolation & purification*; D010455:Peptides / Q000032:analysis
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D003852:Deoxyribonucleoproteins; D009698:Nucleoproteins; D010455:Peptides; D003851:Deoxyribonucleases