Cellular Receptors Flashcards
Types of binding domains of plasma membrane receptors
Ligand-Gated Ion-channel receptors. Enzyme-linked receptors. Cytosine receptors. G-protein coupled receptors.
Nicotinic Acetylcholine receptor
Binding of acetylcholine creates conformational changes to allow Na to diffuse in and K to diffuse out. this creates contraction of the fiber in the cell
Tyrosine Kinase Receptors
Growth factor bind to the receptor to promote dimerization. Intracellular domains of receptor phosphorylates on certain resides. This creates binding sites for signal transducer proteins
Serine-Threonine Kinase Receptors
Used in proteins in the transforming growth factor superfamily. Phosphorylates serine or threonine. Associated with gene transcription factors (β transforming growth factor regulation/proliferation)
Tyrosine Kinase-Associated Receptors
Usually used by growth hormone and prolactin. Binds to JAK kinase factors.
What do JAK kinase factors phosphorylate?
a tyrosine residue on STATs
What do STAT-Ps do?
Enter the nucleus and activate transcription by binding to specific response elements. Activate immune responses and inflammation.
G-Protein Receptor
Nucleotide regulatory proteins that link to intracellular secondary messengers
Examples of secondary messengers
cAMP, cGMP, Ca, DAG, phospyatidylinositides
Lipophilic hormone receptors
Intracellular receptors
Cytosolic receptors
Type of lipophilic hormone intracellular receptor. bound to heat shock proteins. Binding of hormone causes complex to migrate to the nucleus, where it can create positive or negative transcription.
Nuclear receptors
Type of lipophilic hormone intracellular receptor. Found in the nucleus with NO HSP. Hormone binding creates conformational changes that lead to positive or negative transcription.
Ligand
Chemical that binds with high specificity to a receptor
Graves’ Disease
Antibodies against thyroid stimulating hormone receptors
Myasthenia Graves
Antibodies against nicotinic acetylcholine receptors
