Phospholipids bound to acidic nuclear proteins in human B and T lymphocytes

Chromatin fractions (DNA, histones and non-histone chromosomal proteins NHCP) have been isolated from human peripheral B and T lymphocytes using different methods and analyzed in order to identify their lipid content. While DNA and histone fractions do not reveal the presence of lipids, a 2% of phospholipids is present in the NHCP fraction. The phospholipids associated with NHCP present a constant relative ratio among sphingomyelin, phosphatidyl-choline and phosphatidyl-ethanolamine both in B and T lymphocytes, whichever are the extraction procedures employed. These findings are related to the possible dereprssive role of phospholipids on DNA-dependent RNA synthesis.