CLONING AND ANALYSIS OF THE CODING REGION OF THE HISTONE H1-DEGREES-ENCODING GENE FROM RAT PC12 CELLS

We have determined the complete coding sequence of the histone-encodin g H1 degrees gene from rat PC12 cells. Southern and Northern analyses suggest that rat H1 degrees is encoded by a single-copy gene which gen erates an mRNA of about 2.2 kb, Comparison of the rat, mouse and human amino-acid sequences shows that the C-terminal domain of the protein is much more variable than the N-terminal and central domains. Rates o f non-synonymous and synonymous nucleotide substitution have been calc ulated. The rate of non-synonymous substitution is about 2.5-times hig her in the rodent lineage than in the human lineage.