Key transcription factor required for motile ciliogenesis. Activates genes essential for motile cilia formation and function. Its activity is sufficient for ectopic development of cilia that resemble motile cilia. Expressed in floor plate, dorsal forerunner cells, Kupffers vesicle, the floor plate, pronephric ducts and kidney. By hedgehog signaling in the floor plate. In response to injury and stretch. Randomization of the left-right body. Belongs to the FOXJ1 family.