Protein kinase A type I activates a CRE-element more efficiently than protein kinase A type II regardless of C subunit isoform

Abstract

BackgroundProtein 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.ResultsWe 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.ConclusionWe suggest that differential effects of PKAI and PKAII in inducing Cre-luciferace activity depend on R and not C subunit identity.

NF-κB and CREB Are Required for Angiotensin II Type 1 Receptor Upregulation in Neurons

“…Angiotensin II stimulation has also been shown to phosphorylate the cAMP-response element binding protein (CREB) via activation of the p38 MAPK pathway in hypertension [9] , [10] , [11] , [12] . Other signaling cascades that lead to the phosphorylation of CREB include the calcium/Calmodulin kinase (CAMK) pathway [13] , extracellular signal regulated protein kinase (ERK) activation [14] , protein kinase A [15] , and the p38 mitogen activated protein kinase (p38MAPK) pathway [16] . Phosphorylation at Serine 133 results in recruitment of a transcriptional co-activator, CREB-binding protein (CBP) which is essential for transcriptional activation [17] .…”

MicroRNA Regulation of Human Protease Genes Essential for Influenza Virus Replication

“…CRE/CREB signaling is an important cellular process that serves a variety of functions. Most notably with respect to influenza infection, CRE/CREB signaling has been shown to activate protein kinase A (PKA) and thus have a role in protein synthesis [54] . In this study, MST1 and PRSS12 were implicated in CRE/CREB signaling; however, in response to influenza infection, CRE signaling levels in cells treated with siPRSS12 were unchanged compared to both pathway reporter and siNEG controls.…”

The M 2 muscarinic receptor, in association to M 1 , regulates the neuromuscular PKA molecular dynamics

“…27 Also, although RII holoenzymes seem more prone to dissociate than RI, probably due to structural differences, RI are more efficient than RII in inducing CREB response regardless of the C subunit. [28][29][30] R subunits are differently expressed across tissues and exert distinct roles in cell differentiation and growth control. 31,32 RIα and RIIα are widely expressed, RIβ is highly expressed in the nervous tissue and RIIβ in the adipose and hepatic tissues.…”

“…Cα and Cβ subunits display essentially the same activation properties, whereas RIβ‐containing holoenzymes show increased sensitivity to cAMP‐evoked activation than RIα‐containing holoenzymes . Also, although RII holoenzymes seem more prone to dissociate than RI, probably due to structural differences, RI are more efficient than RII in inducing CREB response regardless of the C subunit …”