CAMK1 alpha/CAMK1 Protein, Human (Active, sf9, His, GST)

CAMK1 alpha is a calcium/calmodulin-dependent protein kinase that functions in the calcium-triggered CaMKK-CaMK1 signaling cascade, regulating transcription activators, cell cycle, hormone production, differentiation, actin organization, and neurite outgrowth in response to calcium influx. It recognizes the substrate motif [MVLIF]-x-R-x(2)-[ST]-x(3)-[MVLIF] and controls axonal extension and growth cone motility in hippocampal and cerebellar neurons. Upon NMDA receptor-mediated Ca²⁺ elevation, it promotes dendritic growth, synaptic long-term potentiation (LTP), and ERK2-dependent translational activation. By phosphorylating ARHGEF7/BETAPIX at Ser-694, it enhances ARHGEF7 activity and RAC1 activation, facilitating spine/synapse formation. It also drives neuronal differentiation and neurite outgrowth via MARK2 phosphorylation (Ser-91/92/93/294) and modulates muscle differentiation by phosphorylating HDAC5 (Ser-259/498) for nuclear export. Additionally, it regulates NUMB-mediated endocytosis (phosphorylating NUMB at Ser-276/295) and medulloblastoma cell migration (via ARHGEF7/BETAPIX phosphorylation, by similarity). In diploid fibroblasts, it is essential for cyclin-D1/CDK4 activation during G1 progression and mediates K(+)/ANG2-dependent aldosterone production via CYP11B2 regulation. In vitro substrates include CREB1, ATF1, CFTR, MYL9, and SYN1/synapsin I.