DISSOCIATION OF MINOR SATELLITE FROM THE CENTROMERE IN MOUSE

The minor satellite DNA of mouse is believed to constitute the centrom ere. We report that centromeres of some chromosomes in the Cl1D cells of mouse are not associated with this DNA even though the latter is pr esent on these chromosomes. The satellite DNA was detected distally fr om the centromere and could not be mistaken as a component of the cent romere. We also report that the site of the primary constriction may n ot always coincide with the site of the anti-kinetochore antibody reac tion. Whereas the regions containing the major satellite decondense up on treatment with bisbenzimidazole (Hoechst 33258), the sites carrying minor satellite resist decondensing.