HMG proteins released from the chromatin following incubation of mammalian nuclei with ethidium bromide.
The low-molecular-mass high-mobility group (HMG) chromosomal proteins, namely HMG-14, HMG-17, and HMG-I, which have been found in several proliferating tissues, are released following incubation of nuclei isolated from young rat thymus and from human placenta in a low ionic strength medium containing the intercalating agent ethidium bromide. The amount of HMG proteins released is drug concentration-dependent, but at very high concentrations (20-40 mM) other low- and high-molecular-mass proteins, and even histones, are released. These results suggest a very weak interaction of the HMG proteins with DNA, so that they can be easily detached from the chromatin as a consequence of the interaction of DNA with the intercalating agent.
Pani
B
B
Department of Biochemistry, Biophysics, and Macromolecular Chemistry, University of Trieste, Italy.
Plossi
P
P
Russo
E
E
D000818:Animals; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism*; D002843:Chromatin / Q000187:drug effects / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004996:Ethidium; D006609:High Mobility Group Proteins / Q000378:metabolism*; D006801:Humans; D011257:Pregnancy Proteins / Q000378:metabolism; D051381:Rats; D013950:Thymus Gland / Q000378:metabolism
D002843:Chromatin; D006609:High Mobility Group Proteins; D011257:Pregnancy Proteins; D004996:Ethidium