We previously conducted a proof of principle; dose escalation study in Duchenne 
muscular dystrophy (DMD) patients using the morpholino splice-switching 
oligonucleotide AVI-4658 (eteplirsen) that induces skipping of dystrophin exon 
51 in patients with relevant deletions, restores the open reading frame and 
induces dystrophin protein expression after intramuscular (i.m.) injection. We 
now show that this dystrophin expression was accompanied by an elevated 
expression of α-sarcoglycan, β-dystroglycan (BDG) and--in relevant 
cases--neuronal nitric oxide synthase (nNOS) at the sarcolemma, each of which is 
a component of a different subcomplex of the dystrophin-associated glycoprotein 
complex (DAPC). As expected, nNOS expression was relocalized to the sarcolemma 
in Duchenne patients in whom the dystrophin deletion left the nNOS-binding 
domain (exons 42-45) intact, whereas this did not occur in patients with 
deletions that involved this domain. Our results indicate that the novel 
internally deleted and shorter dystrophin induced by skipping exon 51 in 
patients with amenable deletions, can also restore the dystrophin-associated 
complex, further suggesting preserved functionality of the newly translated 
dystrophin.