Transcription factor specifically required for the formation of motile cilia. Acts by activating transcription of genes that mediate assembly of motile cilia; such as CFAP157. Binds the DNA consensus sequences 5'-HWDTGTTTGTTTA-3' or 5'-KTTTGTTGTTKTW-3' (where H is not G; W is A or T; D is not C; and K is G or T). Activates the transcription of a variety of ciliary proteins in the developing brain and lung.