Cytoplasmic Linker Associated Protein 1 (CLASP1)

CLASP1 belongs to a family of microtubule-associated proteins involved in attachment of microtubules to the cell cortex in animals and plants.In animal cells, CLASP1 is involved in the regulation of microtubule dynamics at the kinetochore and throughout the spindle. CLASP1 localizes preferentially near the plus ends of growing spindle microtubules and is also a component of a kinetochore region they termed the outer corona. A truncated form of CLASP1 lacking the kinetochore-binding domain behaved as a dominant negative, leading to the formation of radial arrays of microtubule bundles that were highly resistant to depolymerization. Microinjection of CLASP1-specific antibodies suppressed microtubule dynamics at kinetochores and throughout the spindle, resulting in the formation of monopolar asters with chromosomes buried in the interior.