The function of MAP1B (microtubule associated protein 1B, ENSG00000131711) is as follows. Facilitates tyrosination of alpha-tubulin in neuronal microtubules (By similarity). Phosphorylated MAP1B is required for proper microtubule dynamics and plays a role in the cytoskeletal changes that accompany neuronal differentiation and neurite extension (PubMed:33268592). Possibly MAP1B binds to at least two tubulin subunits in the polymer, and this bridging of subunits might be involved in nucleating microtubule polymerization and in stabilizing microtubules. Acts as a positive cofactor in DAPK1-mediated autophagic vesicle formation and membrane blebbing. {ECO:0000250, ECO:0000269|PubMed:18195017, ECO:0000269|PubMed:33268592}.