Muscleblind Like Protein 1 (MBNL1)

MBNL1 encodes a C3H-type zinc finger protein, which is similar to the Drosophila melanogaster muscleblind B protein. Drosophila muscleblind is a gene required for photoreceptor differentiation. Several alternatively spliced transcript variants have been described but the full-length natures of only some have been determined.Foci in DM2 were distinguished from DM1 by lower stability of the probe-target duplex, suggesting that a sequence related to the DM1 CUG expansion may accumulate in the DM2 nucleus. Muscleblind proteins, which interact with expanded CUG repeats in vitro, localized to the nuclear foci in both DM1 and DM2. The authors proposed that nuclear accumulation of mutant RNA is pathogenic in DM1, a similar disease process may occur in DM2, and muscleblind may play a role in the pathogenesis of both disorders.