Description
Primary cilium serves as a cellular antenna to sense environmental signals. Ciliogenesis requires the removal of CP110 to convert the mother centriole into the basal body. Actin dynamics is also critical for cilia formation. How these distinct processes are properly regulated remains unknown. Here we show that miR-129-3p, a microRNA conserved in the vertebrates, controlled cilia assembly by down-regulating both CP110 and four proteins critical for actin dynamics, Arp2, Toca1, abLIM1, and abLIM3. Consistently, blocking miR-129-3p repressed cilia formation in cultured mammalian cells, whereas its overexpression potently induced ciliogenesis in proliferating cells and extraordinary cilia elongation. Moreover, inhibition of miR-129-3p in zebrafish embryos suppressed cilia assembly in the Kupffers vesicle and pronephric duct, leading to developmental abnormalities including curved body, pericardial oedema, and randomised left-right patterning. Our results thus unravel a novel mechanism that orchestrates both the centriole-to-basal body transition and subsequent cilia assembly via microRNA-mediated posttranscriptional regulations.