Regulation of splicing by MBNL and CELF family of RNA-binding protein

Myotonic Dystrophy (DM), the most common form of adult-onset muscular dystrophy, comprises at least 2 subtypes, DM1 and DM2. DM1 is caused by the expansion of a CTG repeat located in the 3' untranslated region of the DM protein kinase (DMPK) gene. Recently, the expansion of a CCTG tetranucleotide repeat located in the first intron of the ZNF9 gene was identified as the mutation responsible for DM2. Since both DM1 and DM2 are caused by the expansion of repetitive sequences, some common factors that interact with these sequences might be involved in the pathogenesis of DM. MBNL1 is a candidate for such factors and is thought to be sequestered by the expanded forms of DM transcripts.