BEHAVIOUR OF HISTONES AND CYTOPLASMIC BASIC PROTEINS DURING EMBRYOGENESIS OF JAPANESE NEWT, TRITURUS-PYRRHOGASTER

1. 1. Newt embryo histones during early embryogenesis were analyzed by micro-scale Amberlite CG-50 chromatography using gradient guanidine hydrochloride. In the case of adult newt liver histones, the presence of three bands: FI (minor), FII (major) and FIII (intermediate) were revealed. 2. 2. None of the histones were detected in the very early newt embryos prior to the early gastrula stage. The FIII component appeared first and soon became constant in amount, while the FII component corresponding to slightly lysine-rich histone appeared at the late gastrula stage and increased its amount continuously during early embryogenesis. The chromatographic pattern of histones became similar to the adult newt histones at the tail bud stage. 3. 3. Cytoplasmic basic proteins extracted primarily from yolk granules were similarly fractionated into the three main bands (CFI, CFII and CFIII). The second (CFII) was shown to be reduced in amount during the early embryogenesis. 4. 4. The amino acid composition of embryonic newt histones was shown to be lower in lysine and arginine, but higher in serine and glycine as compared with calf-thymus histones. The resemblance in amino acid composition of embryonic newt histone to cytoplasmic basic proteins has been observed. © 1969.