Enables microtubule minus-end binding activity. Involved in several processes, including establishment of epithelial cell apical/basal polarity; establishment or maintenance of microtubule cytoskeleton polarity; and regulation of microtubule polymerization. Acts upstream of or within in utero embryonic development. Located in axoneme; ciliary basal body; and motile cilium. Colocalizes with microtubule minus-end. Is expressed in brain and lung epithelium. Orthologous to human CAMSAP3 (calmodulin regulated spectrin associated protein family member 3). [provided by Alliance of Genome Resources, Apr 2022]