PAX4 controls the expression of the proteasome assembly chaperon PSMD5 at 3 days after denervation. (A and B) mRNA preparations from denervated (3 and 10 days) muscles from WT, PAX4 KO, α-PAL^NRF-1 KD, and PAX4/α-PAL^NRF-1 KD mice were analyzed by RT-PCR. Means ± SEM are presented as a ratio to WT innervated. N = 4 mice per condition. *, P < 0.05, **, P < 0.005, and ***, P < 0.0005 versus innervated in WT; #, P < 0.05 versus denervated in WT by one-tailed unpaired Student’s t test.