DNA and histone H1 interact with different domains of HMG 1 and 2 proteins.
High mobility group (HMG) proteins 1 and 2 from calf thymus have been digested under structuring conditions (0.35 M NaCl, pH 7.1) with two proteases of different specificities, trypsin and V8. The two proteases give a different but restricted pattern of peptides in a time course digestion study. However, when the interactions of the peptides with DNA are studied by blotting, a closely related peptide from HMG-1 and -2 does not show any apparent binding. This peptide, from the V8 protease digestion, has been isolated by DNA-cellulose chromatography and has the amino acid composition predicted for a fragment containing the two C-terminal domains of the protein, i.e., approximately residues 74-243 for HMG-1. The same peptide shows the only interaction detectable with labelled histone H1. A separate function for the different domains of HMG proteins 1 and 2 is proposed.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D004247:DNA / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases; D006609:High Mobility Group Proteins; D006657:Histones / Q000378:metabolism*; D008970:Molecular Weight; D011485:Protein Binding; D012697:Serine Endopeptidases; D013950:Thymus Gland / Q000378:metabolism; D014357:Trypsin
D000596:Amino Acids; D002868:Chromosomal Proteins, Non-Histone; D006609:High Mobility Group Proteins; D006657:Histones; D004247:DNA; D010450:Endopeptidases; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase; D014357:Trypsin