title: Sequence and characterization of a sperm-specific histone H1-like protein of Mytilus californianus.
abstract: The major protein fraction of the protamine-like PL-II* (phi 2B) from the sperm of Mytilus californianus has been sequenced and characterized. Immunological and sequence analyses unequivocally show that this protein is indeed a member of the histone H1 family. Along with proteins of the histone H1 class, the protein also shows cross-reactivity and sequence identity, in its NH2-terminal region, with the major protamine-like protein component of Mytilus sperm: PL-III (phi 1), of smaller molecular mass. Indeed it is the unusual repetitive sequence motif of the NH2-terminal domain of PL-II* that bestows to this protein its protamine-like nature. Fourier-transform infrared spectroscopy spectroscopy indicates that the protein contains considerable secondary structure: 18% alpha-helix, 21% beta-sheet, 39% turns and bends, 22% random coil. At the higher levels of structure, PL-II* exhibits ionic strength-dependent folding which is indistinguishable from that of histone H5, as monitored by fluorescence anisotropy.
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, British Columbia, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Carlos
authors.forename: L
authors.initials: L
authors.lastname: Jutglar
authors.forename: I
authors.initials: I
authors.lastname: Borrell
authors.forename: D F
authors.initials: DF
authors.lastname: Hunt
authors.forename: J
authors.initials: J
authors.lastname: Ausio
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D049872:Bivalvia; D002843:Chromatin / Q000737:chemistry; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003429:Cross Reactions; D004268:DNA-Binding Proteins; D010450:Endopeptidases; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000032:analysis / Q000737:chemistry; D005454:Fluorescence Polarization; D005583:Fourier Analysis; D006657:Histones / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification; D015151:Immunoblotting; D008297:Male; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000737:chemistry* / Q000302:isolation & purification; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification; D017433:Protein Structure, Secondary; D013055:Spectrophotometry, Infrared; D013094:Spermatozoa / Q000737:chemistry*
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D000939:Epitopes; D006657:Histones; D009687:Nuclear Proteins; D010446:Peptide Fragments; C068699:PL-II protein, Mytilus; D010450:Endopeptidases