Calcium/calmodulin-dependent protein kinase type II subunit alpha

CAMK2A (calcium/calmodulin-dependent protein kinase type II subunit alpha) is a serine/threonine kinase that functions autonomously after Ca²⁺/calmodulin binding and autophosphorylation (UniProt: Q9UQM7). It plays central roles in synaptic plasticity, neurotransmitter release, and long-term potentiation, and regulates dendritic spine development and neuronal migration. The protein also phosphorylates transcription factors including FOXO3, ETS1, and STAT1 in response to calcium and interferon signaling, with emerging roles in ferroptosis regulation and synaptic 2-AG signaling.

CAMK2A is predominantly expressed in the nervous system where it functions as a key component of excitatory NMDAR signaling complexes. UniProt documents mutations in CAMK2A associated with two forms of intellectual developmental disorder—autosomal dominant (MRD53, MIM 617798) and autosomal recessive (MRT63, MIM 618095)—both characterized by global developmental delay, intellectual disability, and in the recessive form, seizures.

In Alzheimer's disease, CAMK2A is significantly upregulated in post-mortem AD brain tissue relative to age-matched controls, with a mean log₂ fold-change of +0.80 across subcellular fractions (Chaparral AD proteomics, TMT-labeled proteomics from P2, P3, S2, and S3 fractions). This elevation may reflect compensatory responses to synaptic dysfunction in AD pathology.