Figure 6.

Disruption of the CArG element does not affect expression of AChE promoter–reporter gene constructs in TA muscle. (A) EMSA using radiolabeled oligonucleotides containing the CArG-box. Note the presence of two major DNA–protein complexes (arrows) in muscle nuclear extracts whose formation was specifically blocked by competition with a 250-fold molar excess of the wild-type (WT) but not the mutant oligonucleotide. (B) Schematic representation of the nucleotides that were mutated (underlined) in the core region of the CArG element in NRAP to generate the mutant CArG-NRAP promoter fragment (mC-NRAP). As shown in A, this mutation resulted in a failure to compete for formation of specific DNA–protein complexes. (C) Expression of β-gal in TA muscles injected with reporter plasmids containing either NRAP or mC-NRAP. Note that disruption of this DNA regulatory element did not affect significantly (P > 0.05; Student’s t test) expression of the reporter gene. Expression of β-gal was normalized to the activity of a coinjected CAT plasmid used to monitor transduction efficiency. Mean ± SE is shown; a minimum of 10 muscles were analyzed per construct.