An enzyme-linked receptor, also known as a catalytic receptor, is a
transmembrane receptor
Cell surface receptors (membrane receptors, transmembrane receptors) are receptor (biochemistry), receptors that are embedded in the cell membrane, plasma membrane of cell (biology), cells. They act in cell signaling by receiving (binding to) ex ...
, where the binding of an extracellular
ligand
In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's el ...
causes
enzymatic activity on the intracellular side.
Hence a catalytic receptor is an
integral membrane protein possessing both
catalytic
Catalysis () is the increase in reaction rate, rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst ...
, and
receptor
Receptor may refer to:
* Sensory receptor, in physiology, any neurite structure that, on receiving environmental stimuli, produces an informative nerve impulse
*Receptor (biochemistry), in biochemistry, a protein molecule that receives and respond ...
functions.
They have two important domains, an extra-cellular ligand binding domain and an intracellular domain, which has a catalytic function; and a single
transmembrane helix. The signaling molecule binds to the receptor on the outside of the cell and causes a conformational change on the catalytic function located on the receptor inside the cell.
Examples of the enzymatic activity include:
*
Receptor tyrosine kinase, as in
fibroblast growth factor receptor. Most enzyme-linked receptors are of this type.
*
Serine/threonine-specific protein kinase
A serine/threonine protein kinase () is a kinase enzyme, in particular a protein kinase, that phosphorylation, phosphorylates the hydroxyl, OH group of the amino acid, amino-acid residues serine or threonine, which have similar side chains. ...
, as in
bone morphogenetic protein
*
Guanylate cyclase, as in
atrial natriuretic factor receptor
Types
The following is a list of the five major families of catalytic receptors:
References
External links
Diagram at scq.ubc.ca
{{Enzyme-linked receptors
Single-pass transmembrane proteins
Transmembrane receptors