This is a simplified diagram showing generalized molecular pathways that induce long-term changes in neuronal activity via CREB. This diagram focuses on extracellular signals that activate membrane proteins commonly found in neurons. Membrane proteins activate various second messenger and intracellular signaling pathways, which eventually target CREB, promoting transcription and translation of target proteins that change neuronal mechanisms in the long term.
The image shows three receptors: G-protein-coupled receptor (GPCR), a calcium channel (such as NMDAR), and a receptor tyrosine kinase channel (TRK). The GPCR acts through a heterotrimeric g-protein to activate adenylate cyclase (AC), increasing intracellular cyclic AMP (cAMP), which acts through phosphorylation cascades and protein kinase A (PKA) to target CREB. The calcium channel increases inctracellular calcium ions (Ca2+), which can act through CaMKIV to target CREB. The TRK can act through ras and MAP kinase to target CREB. CREB promotes transcription and translation of target proteins, and these proteins disperse throughout the neuron to effect long-term changes.

The image was made in Adobe Illustrator.
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Evrae8