Microtubule-associated protein essential for correct brain development (PubMed:30449657). Appears to link the dystrophin/utrophin network with microtubule filaments via the syntrophins. Phosphorylation of DMD or UTRN may modulate their affinities for associated proteins (By similarity). {ECO:0000250|UniProtKB:Q9R1L5, ECO:0000269|PubMed:30449657}. This is the function of MAST1 (microtubule associated serine/threonine kinase 1, ENSG00000105613).