Thermal denaturation and fluorescence study of nucleosomes containing non-histone chromosomal protein HMG2.
Interaction of calf thymus non-histone chromosomal protein HMG2 with H1,H5-depleted nucleosomes from chicken erythrocytes was studied by means of thermal denaturation and an N-(3-pyrene)maleimide fluorescence probe. Under low ionic conditions (2 mM Tris buffer plus EDTA) addition of 1-2 molecules of HMG2 per nucleosome markedly stabilized the segment of the linker DNA against thermal denaturation. Under approximately physiological ionic conditions (0.1 M NaCl) addition of two HMG2 molecules per nucleosome, labeled by N-(3-pyrene)maleimide at the sulfhydryl groups of Cys-110 of histones H3, resulted in a decrease of the pyrene excimer fluorescence corresponding to the slight movement of the sulfhydryl groups of the two histone H3 molecules apart.
Stros
M
M
Institute of Biophysics, Czechoslovak Academy of Sciences, Brno.
Kleinwächter
V
V
D000818:Animals; D002417:Cattle; D002645:Chickens; D004912:Erythrocytes / Q000648:ultrastructure; D006609:High Mobility Group Proteins / Q000302:isolation & purification / Q000502:physiology*; D006358:Hot Temperature; D009707:Nucleosomes / Q000648:ultrastructure*; D011489:Protein Denaturation; D013050:Spectrometry, Fluorescence
D006609:High Mobility Group Proteins; D009707:Nucleosomes