Cell signaling typically involves a three-stage process: Reception, Transduction, and Response.
1. Reception:
In this initial stage, a ligand (signaling molecule) binds to its specific receptor, which may be located on the cell’s plasma membrane, or within the cytoplasm or nucleus. This interaction is highly specific, similar to a key fitting into a lock, and marks the initiation of the signaling process.
2. Transduction:
Once the signaling molecule binds to the receptor, the receptor is activated, often undergoing a conformational change. This activation triggers a cascade of intracellular events known as the signal transduction pathway. During this stage, the signal is relayed through a series of molecules, amplifying the initial message as it progresses through the cell.
3. Response:
Finally, the transduction pathway leads to a specific cellular response. For instance, in the nucleus, this might trigger the transcription of certain genes, ultimately resulting in a certain change.
