title: A dual chromatin organization in the sperm of the bivalve mollusc Spisula solidissima.
abstract: Most of the DNA in the sperm of the bivalve mollusc. Spisula solidissima, is found to be associated with a specific high-molecular-mass, protamine-like component, sharing features common both to protamines and to histones. We have found that this component coexists, in the mature sperm nucleus, with a complete set of histones, including an H1-like histone. Such histones account for approximately 20% of the whole protein content in the sperm chromatin, the overall protein/DNA ratio (w/w) being 0.87. These data, together with micrococcal nuclease digestions in combination with salt fractionation, have allowed us to propose a structural model for this chromatin in which short nucleosomal domains are interspersed in a highly saturated protamine-DNA complex.
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000032:analysis* / Q000235:genetics; D005591:Chemical Fractionation; D002843:Chromatin / Q000032:analysis*; D002845:Chromatography / Q000379:methods; D004247:DNA / Q000032:analysis; D004586:Electrophoresis / Q000379:methods; D008297:Male; D013056:Spectrophotometry, Ultraviolet; D013094:Spermatozoa / Q000032:analysis*
chemical_list: D002843:Chromatin; D004247:DNA