CaMK

CaMKs are Ca²⁺/calmodulin-dependent protein kinases that translate intracellular calcium increases into signaling cascades regulating neuronal transmission, synaptic plasticity, circuit development, cognition, cell-cycle progression, and cancer-related functions^[1][2][3]. Mechanistically, CaMKII gains autophosphorylation-mediated autonomy, whereas CaMKI and CaMKIV depend on CaMKK-dependent phosphoswitch activation, creating distinct pathway logic among related isoforms^[1]. In ischemic stroke models, CaMKII mediates neuronal cell death, neuroinflammation, and endothelial barrier dysfunction, while CaMKK/CaMKIV signaling supports blood-brain barrier integrity and transcriptional activation of neuroprotective molecules^[4][5]. In cardiac models, CaMKIIδ predominates in the heart, where nuclear δB regulates hypertrophic gene expression and cytoplasmic δC affects excitation-contraction coupling and apoptosis^[6]. Compared with related isoforms, CaMKI regulates G₁, whereas CaMKII regulates G₂/M and the metaphase-anaphase transition, supporting isoform-specific experimental design in proliferative disease research^[2]. For experimental applications, KN-93 and KN-62 inhibited RANKL-induced osteoclastogenesis, ERK phosphorylation, CREB activity, cathepsin K expression, and bone resorption^[7]. Structural CAMKK1 studies identified exploitable differences between CAMKK1 and CAMKK2, supporting design of specific inhibitors^[8].