Protein kinase A catalytic subunit alpha isoform (PKA Cα)

The Protein kinase A catalytic subunit alpha (PKA Cα) is an enzyme encoded by the PRKACA gene in humans. It forms part of the PKA holoenzyme, which consists of a dimer of regulatory subunits complexed with two catalytic subunits. Activation occurs through binding of cyclic AMP to regulatory subunits, which liberates the catalytic subunits to phosphorylate serine/threonine residues on diverse substrate proteins. PKA Cα is central to signal transduction for numerous cellular processes, including metabolism, proliferation, cell cycle progression, and transcriptional regulation. It is widely studied for its roles in physiology and disease, especially in endocrine, cardiovascular, and oncological contexts. Isoform-specific functions and regulation are often mediated by its interaction with scaffold proteins (AKAPs), controlling localization and substrate specificity. Aberrant PKA signaling is implicated in diseases such as cancer and endocrine disorders. Selective modulation of PKA Cα activity is therapeutically challenging due to its ubiquitous cellular roles.

Other names

cAMP-dependent protein kinase catalytic subunit alphaPRKACAPKA alphaPKA CαPKA catalytic subunit alpha

Inhibition: Small molecules or peptides block ATP binding or substrate recognition. Activation: Upstream modulators increase intracellular cAMP, triggering dissociation of regulatory/catalytic subunits and activation of the kinase.