A cytological procedure to screen mammalian temperature-sensitive mutants for cell-cycle-related defects

Interphase cells stained with quinacrine dihydrochloride show distinctive fluorescent nuclear patterns according to their position in the cell cycle. These patterns were used to determine whether temperature-sensitive growth mutants of the Syrian hamster cell line BHK-21 are blocked at specific stages of the cell cycle. These cytological studies confirmed the previous conclusion that ts Af8 cell line derived from BHK cells is a GI cell-cycle mutant. The method promises to be of use as an initial probe in screening for cell-cycle mutants.