Primary cilia are sensory organelles essential for signaling and defects in formation, maintenance or structure underlie diverse ciliopathies. Here, we identify lysine demethylase 4A (KDM4A) as a previously unrecognized mediator of ciliogenesis. Using genetic depletion and pharmacologic inhibition, we show that KDM4A is required for cilia assembly and maintenance. Super-resolution imaging reveals KDM4A localization at the basal body, where it distinctively wraps around the centrioles. We uncover a direct interaction between KDM4A and Rootletin (CROCC), a structural protein mediating centriole cohesion, and demonstrate that KDM4A loss increases inter-centriolar distances, implicating basal body architecture in ciliary failure. Together, these findings define a demethylase-centrosome axis that integrates KDM4A activity with organelle biology, revealing new mechanisms underlying ciliogenesis.
Motrapu et al. (Mon,) studied this question.