TABLE 3.

Relative activities of various UCEs

Cell lines stably expressing non-brain and brain forms of WT and mutant UCEs were treated with 120 μg/ml CHX for 6 h. Aliquots (1.5–5.0 μg) of cell lysates were used for UCE assays as described under “Experimental Procedures.” Separate aliquots were subjected to SDS-PAGE and Western blotting with anti-HA Ab. The density of the bands representing the mature form of UCE was determined using a Kodak Image Station 440. The WT values for units of enzyme activity were divided by the density of the band of mature UCE and set to 1.0. The background level of UCE activity in non-transfected cells was less than 1% of the value obtained with WT UCE-transfected cells. The data are the average of three different sets of experimental results. The level of mature F513SfsX113 mutant was too low to evaluate.

Cell line	Relative activity
	Non-brain form	Brain form
WT	1	1
R328C	0.91 ± 0.11	1.15 ± 0.22
H84Q	0.45 ± 0.09	0.58 ± 0.12