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Updated: Jun 4, 2026

A Guide to Production, Crystallization, and Structure Determination of Human IKK1/α
Published on: November 2, 2018
Protein kinase A type I activates a CRE-element more efficiently than protein kinase A type II regardless of C
Øystein Stakkestad1, Anja C V Larsen, Anne-Katrine Kvissel
1Department of Nutrition, Institute for Basic Medical Sciences, University of Oslo, Sognsvannsveien 9, P,O, Box 1046 Blindern, N- 0316 OSLO, Norway.
Background:
Protein kinase A type I (PKAI) and PKAII are expressed in most of the eukaryotic cells examined. PKA is a major receptor for cAMP and specificity is achieved partly through tissue-dependent expression and subcellular localization of subunits with different biochemical properties. In addition posttranslational modifications help fine tune PKA activity, distribution and interaction in the cell. In spite of this the functional significance of two forms of PKA in one cell has not been fully determined. Here we have tested the ability of PKAI and PKAII formed by expression of the regulatory (R) subunits RIα or RIIα in conjunction with Cα1 or Cβ2 to activate a co-transfected luciferace reporter gene, controlled by the cyclic AMP responsive element-binding protein (CREB) in vivo.
Results:
We show that PKAI when expressed at equal levels as PKAII was significantly (p < 0.01) more efficient in inducing Cre-luciferace activity at saturating concentrations of cAMP. This result was obtained regardless of catalytic subunit identity.
Conclusion:
We suggest that differential effects of PKAI and PKAII in inducing Cre-luciferace activity depend on R and not C subunit identity.
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