Mitotic CHO cells and mouse testicular cells were fused with polyethylene glycol. Several types of prematurely condensed chromosomes were observed. From chromosome morphology it was possible to determine that most of the PCC represented mouse cells. Labeling of either the CHO cells in vitro or the testicular cells in vivo with 3H-TdR prior to fusion also demonstrated that the PCC were derived from the mouse cells. In some PCC, 20 chromosomes could be counted, the haploid number for mouse. It is assumed that these PCC were induced in mouse spermatid nuclei.
Animals Cell Fusion