title: The arrangement of H5 molecules in extended and condensed chicken erythrocyte chromatin.
abstract: Chemical cross-linking with dithiobis(succinimidyl propionate) has been used to investigate the relative disposition of neighbouring H5 (H1) molecules in chicken erythrocyte chromatin in the extended (nucleosome filament) and condensed (300 A filament) states; in this chromatin H5 and H1 are interspersed along the nucleosome filament, rather than segregated into blocks, as shown by the nature of the cross-linked dimers and their relative amounts. Detailed analysis of the cross-linked H5 homopolymers from extended chromatin and condensed nuclear chromatin indicates which domains of H5 are in contact (or close proximity) in the two states. Two results suggest a polar, head-to-tail arrangement of H5 molecules along the nucleosome filament. This arrangement persists when chromatin adopts higher-order structure but in the folded state neighbouring basic C-terminal domains, in particular, are more closely juxtaposed than they are in extended chromatin.
mesh_terms: D000818:Animals; D002645:Chickens; D002843:Chromatin / Q000648:ultrastructure*; D003432:Cross-Linking Reagents; D006657:Histones / Q000378:metabolism; D008274:Magnesium / Q000494:pharmacology; D015636:Magnesium Chloride; D009707:Nucleosomes / Q000648:ultrastructure*; D009994:Osmolar Concentration; D011485:Protein Binding
chemical_list: D002843:Chromatin; D003432:Cross-Linking Reagents; D006657:Histones; D009707:Nucleosomes; D015636:Magnesium Chloride; D008274:Magnesium