Selective localization of G protein γ5 subunit in the subventricular zone of the lateral ventricle and rostral migratory stream of the adult rat brain

G proteins play important roles in transmembrane signal transduction, and various isoforms of each subunit, alpha, beta and gamma, are highly expressed in the brain. The G gamma (5) subunit is a minor isoform in the adult brain, but we have previously shown it to be highly expressed in the proliferative region of the ventricular zone in the rat embryonic brain. We show here that G gamma (5) is also selectively localized in a proliferative region in the adult rat brain, including the subventricular zone of the lateral ventricle and rostral migratory stream. The G alpha (i2) subunit colocalized with G gamma (5) in these regions, the two subunits being present in neuronal precursors and ependymal cells but not in proliferating astrocytes. In addition, intense staining of G gamma (5) was seen in axons of the olfactory neurons, which are known to regenerate. These results suggest specific roles for G gamma (5) in precursor cells during neurogenesis so that this isoform might be a useful biological marker.