therapy with antisense oligonucleotide
In this video, medical students from Leiden University Medical Center show how therapy with an antisense oligonucleotide can influence the structure of an incomplete protein by masking a missing link. Like progeria, Duchenne muscular dystrophy (DMD) is a lethal disease which is caused by non a functional protein. For Duchenne and Progeria patients, this approach offers new perspectives.
It illustrates the process:
Proteins are encoded by a gene, which consists of arrays of exons (E) and introns (I). To make proteins, the introns have to be spliced out by the spliceosome. The exons are then joined together and the amino acids (AA) are synthesized. When there is a mutation (STOP) in the gene, the protein cannot be synthesized properly and is therefore not functional. This protein makes the muscle weak, more prone to damage and eventually degenerates. An approach called 'exon skipping' could correct a faulty gene using a molecule called antisense oligonucleotides (AON). What does it do? The AON is designed to target, bind and mask/hide the mutated exon. The hidden exon will be treated as an intron by the spliceosome, and spliced out together with the other introns.
The protein produced after exon skipping will be shorter, but is expected to function better than the original, mutated protein.