title: In vitro induction of uncoiled chromosomes with inhibitors of RNA and protein synthesis.
abstract: When inhibitors of cellular DNA, RNA or protein synthesis are added to the growth medium of human lymphoid cells in G2 phase, these agents produce, within narrow ranges of concentrations, G banded or uncoiled chromosomes in the treated metaphase cells. It is suggested that the induced structural alteration is a consequence of an inhibition of the normal chromosome condensation and fusion of bands taking place between prometaphase and metaphase. This inhibition seems to be due to a partial inhibition of G2 phase synthesis of RNA and protein molecules, necessary for normal chromosome condensation in metaphase. It is found that this condensation can be reversed during a resting period after metaphase.
mesh_terms: D000546:Amanitins / Q000494:pharmacology; D002871:Chromosome Banding; D002877:Chromosomes, Human / Q000187:drug effects* / Q000648:ultrastructure; D003513:Cycloheximide / Q000494:pharmacology; D006801:Humans; D007399:Interphase; D008214:Lymphocytes / Q000648:ultrastructure*; D008677:Metaphase; D008727:Methotrexate / Q000494:pharmacology; D011691:Puromycin / Q000494:pharmacology
chemical_list: D000546:Amanitins; D011691:Puromycin; D003513:Cycloheximide; D008727:Methotrexate