PKA promotes exclusion of exons 14, 15, and 16 of CaMKIIδ.

<p>A, Forskolin treatment activated PKA. HEK-293T cells were transfected with pCI/CaMKIIδ<sub>E13–E17</sub> for 40 hrs and then treated with 10 µM forskolin for 8 hrs. The cells were subjected to Western blots for detection of PKA activity with anti-phosphorylated CREB at Ser133 and anti-CREB. B, Forskolin treatment promoted the exclusion of exons 14, 15, and 16, resulting in an increase in CaMKIIδC expression. HEK-293T cells were transfected with pCI/CaMKIIδ<sub>E13–E17</sub> for 40 hrs and then treated with 10 µM forskolin for 8 hrs. The splicing products were measured with RT-PCR. Each splicing product was quantitated by densitometry, and the percentage of each splicing form was calculated. C, Overexpression of PKA-Cα increased PKA activity. HEK-293T cells were co-transfected with pCI/CaMKIIδ<sub>E12–E17</sub> and pCI/PKA-Cα for 48 hrs. The PKA activity in the cells was measured by phosphorylation of CREB at Ser133 with Western blots. D, Overexpression of PKA-Cα promoted the exclusion of exons 14, 15, and 16 of CaMKII™. HEK-293T cells were cotransfected with pCI/CaMKIIδ<sub>E13–E17</sub> and pCI/PKA-Cα for 48 hrs. The splicing products were measured with RT-PCR. Each splicing product was quantitated by densitometry, and the percentage of each splicing form was calculated. The Data are presented as mean ± S.D. *<i>p</i><0.05 versus control treatment.</p>