Enables microtubule binding activity. Involved in several processes, including axonal transport; positive regulation of insulin secretion involved in cellular response to glucose stimulus; and regulation of synaptic activity. Acts upstream of or within regulation of insulin secretion involved in cellular response to glucose stimulus. Located in dense body; microtubule; and vesicle. Orthologous to human SYBU (syntabulin). [provided by Alliance of Genome Resources, Apr 2022]