Nerve growth factor mRNA in brain: localization by in situ hybridization.

Nerve Growth Factor is a 118 amino acid polypeptide that plays an important role in the differentiation and survival of neurons. The recent discovery that a mRNA that encodes beta Nerve Growth Factor is present in brain suggests that the Nerve Growth Factor gene may not only regulate gene expression of peripheral but also of central neurons. To identify the site(s) of Nerve Growth Factor mRNA production in the brain and to determine which cells express the Nerve Growth Factor gene, the technique of in situ hybridization was employed. A 32P-labeled RNA probe complementary to Nerve Growth Factor mRNA hybridized to cells in the stratum granulosum of the dentate gyrus and the stratum pyramidale of the hippocampus. These observations identify for the first time cellular sites of Nerve Growth Factor gene expression in the central nervous system, and suggest that Nerve Growth Factor mRNA is produced by neurons.