Enables microtubule minus-end binding activity. Involved in cytoplasmic microtubule organization and nematode larval development. Located in microtubule minus-end. Expressed in hypodermis; intestine; nervous system; and pharynx. Human ortholog(s) of this gene implicated in complex cortical dysplasia with other brain malformations. Is an ortholog of human CAMSAP1 (calmodulin regulated spectrin associated protein 1); CAMSAP2 (calmodulin regulated spectrin associated protein family member 2); and CAMSAP3 (calmodulin regulated spectrin associated protein family member 3).