Developmental expression of the chicken nerve growth factor receptor gene during brain morphogenesis

Neural development proceeds in an ordered fashion in which a variety of genetic and epigenetic factors exert an influence at well defined times. Using a cloned chicken genomic fragment for the nerve growth factor (NGF) receptor, we have detected strong expression in chicken brain at early stages of embryonic development. Expression of the receptor gene was greatly diminished at birth. This pattern of NGF receptor mRNA level was observed in all cranial regions and was further correlated with the appearance and disappearance of cell surface receptors. The transient developmental expression of NGF receptors in chick brain and the requirement for receptors to mediate NGF's effects suggests that NGF may possess a broader range of actions during development of the nervous system.