Deoxyribonucleic acid in germinal vesicles of oocytes of Rana pipiens.

The amount of DNA isolated from germinal vesicles of Rana pipiens oocytes is similar to that isolated from whole unfertilized eggs, and this suggests that oocyte nuclei are the source ofmuch of the DNA obtained from whole eggs. Fluorometric determinations of the isolated DNA show the presence of 0.004 microgram of DNA equivalents per germinal vesicle. Similar values were obtained by estimations from comparisons of the cesium chloride densitygradient profiles of sample DNA and a known amount of reference DNA from Pseudomonas aeruginosa. The buoyant density of DNA prepared from isolated germinal vesicles is the same as that of frog-liver DNA, 1.706 grams per cubic centimeter, as determined by equilibrium sedimentation in a cesium chloride density gradient.