TABLE 2.

A complementation assay for p53 function in Ad12-induced RNU2 fragility

p53 expression	MOI	RNU2 fragilitya as shown by:
		% of cells	% of RNU2 loci
Wild type	10	32	23
V143A	10	29	20
R175H	10	22	16
R248W	10	26	19
R273H	10	28	21
Control	0	9	5

^aAt least 100 metaphases were examined for each datum. The p53 expression vectors have been described previously (5, 35). The complementation assay with Saos-2 cells was performed as detailed in Materials and Methods. All data were normalized to transfection efficiency as judged by the β-galactosidase color assay (46). Control cells were transfected with 20 μg of the pCH110 β-galactosidase expression vector. Note that the values for percent fragility refer to total number of metaphases examined; when we assumed a 100% infection and corrected for transfection efficiency (30 to 40%), RNU2 fragility was usually observed in >70% of the cells transfected with wild-type or mutant p53.