Probable transcription factor. Involved in kidney development, acting synergistically with lhx1/lim-1 in pronephric morphogenesis during the tailbud stages. Expression becomes spatially localized at mid-gastrula stages and is localized to the nervous system (midbrain, hindbrain, spinal cord), sensory organs (optic vesicle and stalk, otic vesicle), visceral arches, developing excretory system (pronephros, pronephric duct, rectal diverticulum, proctodaeum) and thryoid gland. Splicing does not appear to be tissue-specific. Splicing is temporally regulated. Isoform 3 is expressed both maternally and zygotically, whereas isoform 2 is exclusively zygotic. Expression is highest in embryos from stage 12 on, with expression levels remaining constant throughout embryogenesis. By activin. Weakly by bFGF.