Cellular and subcellular localization of protein I in the peripheral nervous system.

Abstract

The cellular and subcellular distribution of protein I, a major brain phosphoprotein, was studied in the rat peripheral nervous system. The levels of protein I in various peripheral nerves and innervated peripheral tissues were determined by radioimmunoassay and radioimmunolabeling of polyacrylamide gels. Protein I is present throughout the peripheral nervous system. Denervation studies of adrenal medulla and iris suggested that the protein I contained in peripheral tissues is localized to the neuronal elements innervating those tissues. Protein I was enriched in neurotransmitter vesicle fractions of peripheral nervous tissue. Protein I appeared to be transported from cell bodies to axon terminals at least partly in association with neurotransmitter vesicles.