- A tyrosine-rich domain within homeodomain transcription factor Nkx2-5 is an essential element in the early cardiac transcriptional regulatory machinery. Elliott, D.A., Solloway, M.J., Wise, N., Biben, C., Costa, M.W., Furtado, M.B., Lange, M., Dunwoodie, S., Harvey, R.P. Development (2006)