Enzyme –coupled receptor signalling:
What are enzyme-coupled receptors?
Signal molecule is a dimer:
physically cross-links 2 receptor
molecules.
Signal molecule is a
monomer: induces a
conformational change causing
receptors to dimerise.
4 examples of enzyme coupled receptor (there are more than 4 types):
1. Receptor tyrosine kinases – autophosphorylates specific tyrosines. The most
numerous type of enzyme-coupled receptor.
2. Receptor serine/ threonine kinases – autophosphorylates specific serines or
threonines.
3. Histidine-kinase-associated receptors – directly autophosphorylates histidines.
Transfers the phosphoryl group to a second intracellular signalling protein.
4. Tyrosine-kinase-associated receptors – no intrinsic enzymatic activity. Directly
recruit cytoplasmic tyrosine kinases.
The various domains of receptor tyrosine
kinases: (don’t learn all the info in the pic, it
is only to show how varied the RTKs can be):
GCPRs
=>
How do receptor tyrosine kinases
receptors work?
Receptor tyrosine kinase
(RTK) signalling: =>
Example 1: Ras activation
What are enzyme-coupled receptors?
Signal molecule is a dimer:
physically cross-links 2 receptor
molecules.
Signal molecule is a
monomer: induces a
conformational change causing
receptors to dimerise.
4 examples of enzyme coupled receptor (there are more than 4 types):
1. Receptor tyrosine kinases – autophosphorylates specific tyrosines. The most
numerous type of enzyme-coupled receptor.
2. Receptor serine/ threonine kinases – autophosphorylates specific serines or
threonines.
3. Histidine-kinase-associated receptors – directly autophosphorylates histidines.
Transfers the phosphoryl group to a second intracellular signalling protein.
4. Tyrosine-kinase-associated receptors – no intrinsic enzymatic activity. Directly
recruit cytoplasmic tyrosine kinases.
The various domains of receptor tyrosine
kinases: (don’t learn all the info in the pic, it
is only to show how varied the RTKs can be):
GCPRs
=>
How do receptor tyrosine kinases
receptors work?
Receptor tyrosine kinase
(RTK) signalling: =>
Example 1: Ras activation
