Electrophoretically identical histones from ribosomes and chromosomes of chicken liver

There are at least two sources of basic protein in cells: the chromosomes which contain histone, and the ribosomes which contain basic proteins whose chemical properties suggest similarities to histones. Since chromosomes and ribosomes are thought to have intimately related roles in gene action, the basic proteins of these organelles may also have related properties. To investigate this possibility the electrophoretic properties of basic ribosomal proteins and chromosomal histones of chicken liver were compared. Zone electrophoresis in starch gel demonstrates rich patterns of protein bands from both sources. Most of the bands from chromosomal histone have the same relative mobilities as the majority of bands from ribosomal basic protein. On the basis of this intimate similarity, we have made the simplifying conclusion that these ribosomal and chromosomal proteins constitute a general class of basic proteins we call histones. These electrophoretic results suggest that ribosomes and chromosomes contain the same kinds of histone molecules, and that chromosome and ribosome production are related by their dependence upon biosynthesis of histones within the nucleus.