The Primary Structure of Histone H1 from Sperm of the Sea Urchin Parechinus angulosus 2. Sequence of the C‐Terminal CNBr Peptide and the Entire Primary Structure

The primary structure of sperm histone H1parecrJinus has been determined. H1parechinus consists of a polypeptide chain of the following 248 amino acid residues: Pro‐Gly‐Ser‐Pro‐Gln‐Lys‐Arg‐Ala‐Ala‐Ser‐Pro‐Arg‐Lys‐Ser‐Pro‐Arg‐Lys‐Ser‐Pro‐Lys‐Lys‐Ser‐Pro‐Arg‐Lys‐Ala‐Ser‐Ala‐Ser‐Pro‐Arg‐Arg‐Lys‐Ala‐Lys‐Arg‐Ala‐Arg‐Ala‐Ser‐Thr‐His‐Pro‐Pro‐Val‐Leu‐Glu‐Met‐Val‐Gln‐Ala‐Ala‐Ile‐Thr‐Ala‐Met‐Lys‐Glu‐Arg‐Lys‐Gly‐Ser‐Ser‐Ala‐Ala‐Lys‐Ile‐Lys‐Ser‐Tyr‐Met‐Ala‐Ala‐Asn‐Tyr‐Arg‐Val‐Asp‐Met‐Asn‐Val‐Leu‐Ala‐Pro‐His‐Val‐Arg‐Arg‐Ala‐Leu‐Arg‐Asn‐Gly‐Val‐Ala‐Ser‐Gly‐Ala‐Leu‐Lys‐Gln‐Val‐Thr‐Gly‐Thr‐Gly‐Ala‐Ser‐Gly‐Arg‐Phe‐Arg‐Val‐Gly‐Ala‐Val‐Ala‐Lys‐Pro‐Lys‐Lys‐Ala‐Lys‐Lys‐Thr‐Ser‐Ala‐Ala‐Ala‐Lys‐Ala‐Lys‐Lys‐Ala‐Lys‐Ala‐Lys‐Lys‐Lys‐Ala‐Ala‐Ala‐Ala‐Lys‐Arg‐Lys‐Ala‐Ala‐Ala‐Lys‐Ala‐Lys‐Lys‐Ala‐Lys‐Lys‐Pro‐Lys‐Lys‐Lys‐Ala‐Ala‐Lys‐Lys‐Ala‐Lys‐Lys‐Pro‐Ala‐Lys‐Lys‐Ser‐Pro‐Lys‐Lys‐Ala‐Lys‐Lys‐Pro‐Ala‐Lys‐Lys‐Ser‐Pro‐Lys‐Lys‐Lys‐Lys‐Ala‐Lys‐Arg‐Ser‐Pro‐Lys‐Lys‐Ala‐Lys‐Lys‐Ala‐Ala‐G1 y‐Lys‐Arg‐Lys‐Pro‐Ala‐Ala‐Lys‐Lys‐Ala‐Arg‐Arg‐Ser‐Pro‐Arg‐Lys‐Ala‐Gly‐Lys‐Arg‐Arg‐Ser‐Pro‐Lys‐Lys‐Ala‐Arg‐Lys. The protein consists of three domains. Compared to other HI and H5 histones, there is a very similar hydrophobic central domain and the carboxyl‐terminal domain is very rich in lysine and alanine. Hlparechinus is similar to H5 histones in that the carboxyl‐terminal domain also contains many arginine residues close to the carboxyl terminus. The carboxyl‐terminal domain of HIparechinusappears to have been constructed by a series of variable duplications. The amino‐terminal domain of H1parechinusis longer and quite different to that of other H1 and H5 histones and is characterized by a repeating tetrapeptide of the general type Ser‐Pro‐(basic)2. The known sequence of a histone H1 gene from Psammechinus miliaris [Schaffner, W. et al. (1978) Cell, 14, 655–6711 is compared to the sequence of H1parechinus. Again the central hydro‐phobic domains are similar whereas the amino terminal domains are very different. The functions of the various domains of sperm histone H1parechinus are discussed. Copyright © 1980, Wiley Blackwell. All rights reserved