TABLE 5.

Incorporation of [³H]leucine into proteins by HEK-293 cells subjected to various treatments^a

Cell treatment	Cycloheximide	Incorporation of [3H]Leu (cpm/mg of protein)b	% Inhibitionc
None	−	117,178 ± 16,780
Negative silencing control	−	110,734 ± 10,073	5.5
GTPBP3 siRNA	−	93,157 ± 5,739*	20.5
None	+	3,398 ± 210
Negative silencing control	+	3,109 ± 167	8.5
GTPBP3 siRNA	+	2,464 ± 196**	27.5

^aCells, untreated (none) or treated as indicated, were incubated for 1 h with [³H]leucine, in the presence (+) or in the absence (−) of cycloheximide (200 μg/ml), as described in Materials and Methods.

^bEach value is the mean ± standard deviation from four different experiments with duplicated samples. Differences from the negative silencing control values were considered significant at P < 0.05 (*) and P < 0.005 (**). The values obtained with cells transfected with the negative silencing control were not found to be significantly different from the corresponding values in the cells without treatment (None).

^cData are expressed as percent inhibition of [³H]leucine incorporation into proteins with respect to untreated cells (None).