H2B nucleohistone ? phospholipid interactions. Thermal denaturation and ultrastructural analysis

Abstract
Sphingomyelin, phosphatidylserine, bovine lecithin and phosphatidylethanolamine modify the thermal stability of H2B-DNA complexes, by inducing stabilization at 0.3 and 0.6 H2B:DNA weight ratios and destabilization at 0.8, 1.0 and 1.5 ones. The ability of phospholipids to modify the arrangement of nucleohistone is confirmed by ultrastructural analysis which indicates a competitive action of these molecules during the nucleoprotein assembly. A possible regulatory role of phospholipids on native chromatin is proposed.