Microtubule-associated protein that bundle and stabilize adjacent microtubules (MT) of the cell cortex. Confers MT resistance to the drug oryzalin. Promotes the formation of a planar network of antiparallel microtubules. Forms a dimer (By similarity). Binds to MT, mostly with coaligned MT, both between parallel or antiparallel, forming thick bundles. Bundles polymerized MT via the formation of 25-nm crossbridges with cortical MT. Present in MT cortical arrays. Binds the preprophase band and the prophase spindle microtubule during prophase. Binds MT during anaphase. Associates also with phragmoplast; binds MT of young emerging phragmoplasts but don't binds along MT when the disk-shaped phragmoplasts transform into a ring-shaped, centrifugally expanding structure. At this time, accumulates in the cell plate and associates with the surface of the separated nuclei. Later traverses the newly formed cross wall, probably in association with plasmodesma. Expressed throughout the cell cycle. Belongs to the MAP65/ASE1 family.