Amino-terminal sequence of a Saccharomyces cerevisiae nuclear protein, NHP6, shows significant identity to bovine HMG1

Several nonhistone chromatin proteins (NHPs) have been isolated from Saccharomyces cerevisiae nuclei. They have molecular masses and amino acid compositions typical of the high mobility group (HMG) proteins from higher eukaryotic cells. Polyclonal antisera raised against two of the NHPs have been used in immunoblots of proteins from subcellular fractions of yeast to show that the NHPs are indeed nuclear. In addition, the amino-terminal amino acid sequences of several of the NHPs were determined. Importantly, the amino-terminal sequence of one of the proteins, NHP6, has significant (60%) identity with a stretch of amino acids in calf thymus HMG1.