CYTOCHEMICAL STUDIES ON CHROMOSOME ULTRASTRUCTURE

This paper deals with the staining of nuclear proteins, presumably histones, in the meitoic chromosomes of the prophase nuclei of lily microsporocytes. In the pachytene chromosones the lateral element of the synaptinemal complex was particularly reactive with alcoholic PTA. The reactive material was extractable with dilute acid, and staining was inhibited by prior acetylation. Various in vitro quantative studies were performed on the PTA reactivity of isolated histones and deoxyribonucleohistones. These studies suggest that the lateral element of the synaptinemal complex may well contain a histone which may be synthesized in the early part of prophase. © 1969 Academic Press, Inc.