MBNL1 and Huntington disease: Furthermore, the HTT mRNA with the expanded (CAG)n gains the ability to sequester RBPs, such as MBNL1 in HD fibroblasts and nucleolin in HD transgenic mouse brains, possibly causing a splicing misregulation of MBNL1 target pre-mRNAs, nucleocytoplasmic transport impairment and nucleolar stress [151,152,153,154].