Primary structure of histone H2B from gonads of the starfish Asterias rubens

Publisher Website
Google Scholar
Abstract
The complete amino acid sequence (121 residues) of histone H2B from gonads of the starfish Asterias rubens was established from structural data obtained essentially from large fragments generated by cleavage of histone H2B at aspartyl residue and by limited hydrolysis of the dimer H2A-H2B with mouse submaxillary gland protease. No real sequence homology can be found between the amino-terminal sequence (residues 1-21) of starfish and calf H2B. One non-conservative substitution (serine-32 in calf .fwdarw. lysine-28 in starfish) leads to the presence of a cluster of 8 basic residues (sequence 23-30) and to the disappearance of a potential site of phosphorylation. A particular structural feature of starfish histone H2B is the presence of N-dimethylproline at its amino-terminal end. By comparison with N-terminal acetylation, which is commonly found in histones, N-terminal methylation is rarely observed. At the present time the functional significance of the N-terminal methylation as well as that of the proline-rich nature of the amino-terminal sequence of the starfish histone H2B remain to be defined.