HISTONES AND DIFFERENTIATION

Abstract

Histone is present in the nuclei and chromosomes of frog embryos not only after gastrulation but also at earlier stages. Nucleohistone is present in embryos which never differentiate but in which cell division continues and nuclei become smaller. In the larger nuclei of early embryos there may be no staining with alkaline fast green. This is thought to be a dilution effect. The picric acid-bromphenol blue procedure for nuclear basic proteins was also used. Staining of the yolk platelets is described and the role of histone in early development discussed.