Adenovirus vector-directed expression of the neurotrophin-3 receptor (TrkC) in mouse astrocytes

In the present article we report the generation of a neurovirological reage nt, an adenovirus vector that efficiently delivers the gene for the Neurotr ophin-3 (NT-3) receptor, TrkC. Using this AdTrkC vector, we examined the in duction of the expression of the above neurotrophin receptor in pure cultur es of mouse astrocytes, a glial cell type that does not constitutively expr ess this gene. Infection of astrocytes at an optimal dose of 100-200 plaque forming units (p.f.u.) per cell, induced expression of specific mRNA, as d emonstrated by RT PCR and Northern blot. This mRNA was translated to produc e a mean of 20,157 biologically active receptor molecules per astrocyte wit h a Kd of 4.1 x 10(-11) M, as demonstrated by I-125-NT-3 binding. After 2D electrophoresis, the mature glycoprotein and some precursors were recognise d by antibodies raised against the carboxy-terminal peptide of Trk. Binding of the ligand induced autophosphorylation of TrkC and H-3-thymidine incorp oration in transduced cells. These results demonstrate that our AdTrkC vect or efficiently mediates the expression of high-levels of biologically activ e NT-3 receptors.