Microtubule plus-end tracking protein that promotes the stabilization of dynamic microtubules. Required for several aspects of mitotic spindle formation including the formation of the overlapping central spindle microtubules and kinetochore attachment. Required for the incorporation of tubulin subunits at the plus ends of kinetochore microtubules during poleward microtubule flux. Acts antagonistically to Klp10A and Klp67A to maintain metaphase spindle length. Also required for guidance of CNS axons downstream of Abl. May function to identify a subset of microtubules that probe the peripheral growth cone domain, where guidance signals exert their influence on cytoskeletal organization. Also required during oogenesis for the organization of the polarized microtubule network inside the 16-cell cyst that ensures oocyte differentiation. Interacts with CLIP-190 and microtubules. Localizes to punctate cytoplasmic foci in interphase. Concentrates on spindle microtubules from prophase to late anaphase. Accumulates on the mid-part of the central spindle during telophase where it remains until cleavage. Subsequently appears at the periphery of the reforming karyomeres. Also localizes to the spindle remnant, cleavage furrows and the fusome of the 16-cell ovarian cyst. Localizes to the axonal growth cone within neurons. Expressed in testis and ovary. Expressed throughout development, although expression is low in pupae. At late developmental stages expression becomes pronounced in muscles and the nervous system, particularly within the intersegmental nerve b (ISNb). Belongs to the CLASP family.