Has a negative effect on cell proliferation. Interacts with FGF2 with a low affinity. Highly expressed in the kidney, brain and lung. Weakly expressed in the muscle, thymus, lymph node, stomach, intestine, colon and liver. Expressed in fetal cartilaginous structures like the nasal cartilage, the ribs and the sternum as well as in the cartilaginous rudiments of developing bones such as the vertebrae and the pelvic bone. High expression is found in the muscles of the tongue and the diaphragm. First detected at embryonic day 7 and became clearly visible at day 11 and increased until day 17.