Fig. 4.

PKA is required for the stability and processing of Gli proteins. (A,C) Levels of full-length Gli2 and Gli3 are not affected by the partial loss of PKA activity in PKA-deficient embryos, whereas there is a moderate decrease in the level of Gli3R (C). (B,D) Total loss of PKA activity in PKA-null embryos drastically reduces the levels of full-length Gli2 and Gli3, which are almost undetectable, suggesting that PKA is important for the stability of activated full-length Gli2 and Gli3. qPCR experiments showed that RNA levels for Gli3 and Gli2 are reduced 2.2±0.1-fold and 1.7±0.1-fold, respectively, in PKA-null embryos, which is not sufficient to explain the decrease in level of the full-length Gli proteins.