Extracellular domain

Definition

The extracellular domain is the portion of a cell surface receptor that extends outside the cell. It interacts with signaling molecules, triggering intracellular responses.

5 Must Know Facts For Your Next Test

1. The extracellular domain is critical for ligand binding, initiating signal transduction.
2. It often undergoes conformational changes upon ligand binding.
3. This domain can be targeted by drugs to modulate cellular responses.
4. Extracellular domains are found in various types of receptors, including G-protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs).
5. Mutations in the extracellular domain can lead to dysfunctional signaling and diseases.

Review Questions

Related terms

Ligand: A molecule that binds specifically to a receptor site of another molecule.

G-Protein-Coupled Receptor (GPCR): A large family of cell surface receptors that interact with G-proteins and initiate signal transduction pathways.

Receptor Tyrosine Kinase (RTK): A type of cell surface receptor that phosphorylates tyrosine residues on itself and other proteins upon ligand binding, leading to signal transduction.