Transcription regulator specifically required for multiciliate cell differentiation. Acts in a multiprotein complex containing E2F4 and E2F5 that binds and activates genes required for centriole biogenesis. Activates genes required for centriole assembly (plk4, cep152) and genes specifically required for motile cilia formation (foxj1). Also promotes the deuterosome pathway of centriole biogenesis by activating expression of ccdc67/deup1, but not its paralog cep63. Component of the EDM complex, at least composed of e2f4, e2f5, mcidas and tfdp1. Expressed in multiciliate differentiating cells. Expression is lost by stage 26, when multiciliate cells in the skin are fully differentiated, but is then detected in the developing nephrostomes of the kidneys where multiciliate cells form at later stages. Down-regulated by Notch signaling. The TIRT domain mediates interaction with e2f4 and tfdp1. Belongs to the geminin family. Truncated N-terminus.