The nuclear localization and transcriptional activity of the NF-ATc family of transcription factors, essential to many developmental, differentiation, and adaptation processes, are determined by the opposing activities of the phosphatase calcineurin, which promotes nuclear accumulation of NF-ATc, and several kinases, which promote cytoplasmic accumulation. Many reports suggest that protein kina...

Cyclic adenosine monophosphate (cAMP) has been implicated in the execution of diverse rhythmic behaviors, but how cAMP functions in neurons to generate behavioral outputs remains unclear. During the defecation motor program in C. elegans, a peptide released from the pacemaker (the intestine) rhythmically excites the GABAergic neurons that control enteric muscle contractions by activating a G pr...

The cardiac Na(+)/Ca(2+) exchanger 1 (NCX1) is an important regulator of intracellular Ca(2+) homeostasis and cardiac function. Several studies have indicated that NCX1 is phosphorylated by the cAMP-dependent protein kinase A (PKA) in vitro, which increases its activity. However, this finding is controversial and no phosphorylation site has so far been identified. Using bioinformatic analysis a...

During cardiac ischaemia antiarrhythmic n-3 polyunsaturated fatty acids (PUFAs) are released following activation of phospholipase A2, if they are in the diet prior to ischaemia. Here we show a positive lusitropic effect of one such PUFA, eicosapentaenoic acid (EPA) in the antiarrhythmic concentration range in Langendorff hearts and isolated rat ventricular myocytes due to activation of protein...

BACKGROUND Post-transcriptional processing of pre-mRNA takes place in several steps and requires involvement of a number of RNA-binding proteins. How pre-mRNA processing is regulated is in large enigmatic. The catalytic (C) subunit of protein kinase A (PKA) is a serine/threonine kinase, which regulates numerous cellular processes including pre-mRNA splicing. Despite that a significant fraction ...

In this study, we investigate the nuclear quantum effects (NQEs) on acidity constant (pKA) of liquid water isotopologs under ambient condition by path integral molecular dynamics (PIMD) simulations. We compared simulations using a fully explicit solvent model with classical polarizable force field, density functional tight binding, and ab initio theory, which correspond to empirical, semiempiri...

Background—Recent studies of b-adrenergic receptor (b-AR) subtype signaling in in vitro preparations have raised doubts as to whether the cAMP/protein kinase A (PKA) signaling is activated in the same manner in response to b2-AR versus b1-AR stimulation. Methods and Results—The present study compared, in the intact dog, the magnitude and characteristics of chronotropic, inotropic, and lusitropi...

Long-term potentiation (LTP) in the hippocampus is a possible mechanism for mammalian learning and memory in which protein kinases play critical roles. We have investigated the involvement of cyclic AMP-dependent protein kinase (PKA) in LTP by directly studying its activation. We developed an in vitro assay which is useful for selective and accurate measurement of stimulus-induced changes in PK...

Heterotrimeric G proteins and protein kinase A (PKA) are two important transmitters that transfer signals from a wide variety of cell surface receptors to generate physiological responses. The established mechanism of PKA activation involves the activation of the Gs-cAMP pathway. Binding of cAMP to the regulatory subunit of PKA (rPKA) leads to a release and subsequent activation of a catalytic ...

BACKGROUND AND PURPOSE Myocardial cAMP elevation confers cardioprotection against ischaemia/reperfusion (I/R) injury. cAMP activates two independent signalling pathways, PKA and Epac. This study investigated the cardiac effects of activating PKA and/or Epac and their involvement in cardioprotection against I/R. EXPERIMENTAL APPROACH Hearts from male rats were used either for determination of ...