CCDC61 is a microtubule-binding centrosomal protein essential for proper centrosome organization and function. Structurally, CCDC61 is a paralog of SAS6 that forms linear filaments through homodimerization interfaces and directly binds microtubules 1. During interphase, CCDC61 localizes to mother centriole subdistal appendages where it functions in anchoring microtubules and maintaining centrosome positioning 2. CCDC61 physically interacts with CEP170, an interaction independent of the CEP250/CROCC linker, and is required for centriole cohesion through its role at subdistal appendages 2. During mitosis, CCDC61 regulates spindle microtubule organization into symmetrical structures and is essential for proper chromosome 19 3. The protein also promotes ciliary functions by facilitating basal body-associated structure assembly 1, though it plays a non-essential role in ciliogenesis 2. Clinically, CCDC61 mutations have been identified in relapsing polychondritis patients, suggesting potential disease relevance 4, though functional validation of this association remains incomplete.