LOCALIZATION OF THE 2 PROTEIN-KINASE-C-BETA MESSENGER-RNA SUBTYPES INCAT VISUAL-SYSTEM

Protein kinase C (PKC) consists of a family of different subtypes enco ded by different PKC genes. We investigated the distribution of PKC be ta 1 and PKC beta 2 in the visual system of the adult cat by in situ h ybridization using oligonucleotide probes complementary to the PKC bet a 1 and PKC beta 2 mRNAs, two splicing variants of the same gene trans cript. In the primary visual cortex PKC beta 1 and PKC beta 2 were bot h present. The laminar distribution patterns found for the two PKC sub types were identical. A remarkable finding was the difference between the laminar distribution of the PKC beta s in areas 17 and 18 when com pared with area 19. In all three areas the highest expression levels w ere found in layer VI, moderately high levels were found in layers II, III and V, while layer I was devoid of signal. In area 17 and 18 laye r IV stood out by its low PKC beta signal. In sharp contrast, layer IV of area 19 was indiscernible from the superficial layers because of a n evenly high signal. In the dLGN of the adult cat PKC beta 1 and PKC beta 2 mRNAs were distributed rather homogeneously over the different layers, but the expression levels for PKC beta 1 were clearly higher t han those for PKC beta 2.