Characteristics of the nerve growth factor receptors and a nerve growth factor receptor-nerve growth factor covalent complex

Nerve growth factor is a polypeptide hormone that is required for the normal growth and development of the embryonic sensory and sympathetic nervous systems. On these cells, there are two different receptors for the nerve growth factor. Recently, these receptors have been isolated from three cell types and shown to have essentially the same binding characteristics. Molecular weights for receptors from two of these cell types, embryonic sensory and rat pheochromocytoma cells, have been determined. In addition, the formation of a covalent nerve growth factor, nerve growth factor receptor complex, has been investigated on embryonic sensory and sympathetic neurons. The formation of this covalent complex containing ¹²⁵I-beta nerve growth factor is prevented by the addition of excess unlabeled nerve growth factor or by the addition of sodium fluoride and dinitrophenol. This complex forms at 4° 22° and 37° indicating that it is occurring on the cell surface. A disulfide bond is involved in the formation of this covalent complex.