title: Effects of acetic acid-alcohol, trypsin, histone 1 and histone fragments on Giemsa staining patterns in chromosomes.
abstract: In an effort to minimize subjective bias, a classification scheme was devised to assess Giemsa staining patterns obtained with experiments involving acetic acid-alcohol and exogenously applied histone 1 and polypeptides. A single rinse of metaphase preparations with acetic acid-alcohol quantitatively reduced Giemsa dye binding. Acid-alcohol irreversibly changed the conformation of H1 and its ability to interfere with trypsin G-banding. Our results suggest that, in addition to protein extraction, acid-alcohol may alter the conformation of acid-insoluble components of metaphase chromosomes. The carboxy-terminal polypeptide (residues 73--212) from NBS cleavage of H1 was an effective inhibitor of Giemsa staining and trypsin G-banding. However, this polypeptide which is preferential for supercoiled DNA was much less efficient in inhibiting Giemsa staining of trypsinized metaphase chromosomes. The molecular consequences of these experiments are discussed.
mesh_terms: D000085:Acetates / Q000494:pharmacology; D001399:Azure Stains; D002871:Chromosome Banding; D002877:Chromosomes, Human / Q000187:drug effects / Q000648:ultrastructure*; D000431:Ethanol / Q000494:pharmacology; D005404:Fixatives / Q000494:pharmacology*; D006657:Histones / Q000494:pharmacology*; D006801:Humans; D010446:Peptide Fragments / Q000494:pharmacology; D010640:Phenothiazines; D014357:Trypsin / Q000494:pharmacology*
chemical_list: D000085:Acetates; D001399:Azure Stains; D005404:Fixatives; D006657:Histones; D010446:Peptide Fragments; D010640:Phenothiazines; D000431:Ethanol; D014357:Trypsin