For most, but not all, RTKs, the weakly active kinase in each subunit is phosphorylate a key tyrosine in the activation loop of the other subunit (trans-phosphorylation)

TLS Online TPP Program

#Id: 9078

#XL - T Zoology

GRK–β-arrestin pathway, suppress signaling by GPCRs, actually functions as a switch, turning off signaling by G proteins and turning on other signaling pathways.

TLS Online TPP Program

#Id: 9079

#XL - T Zoology

Muscarinic acetylcholine receptors coupled to a Gαi protein & found in cardiac muscles. 

TLS Online TPP Program

#Id: 9080

#XL - T Zoology

Binding of acetylcholine triggers the opening of an associated K+ channel  in the plasma membrane via the Gβγ subunit of a Gi protein

TLS Online TPP Program

#Id: 9081

#XL - T Zoology

The increase in K+ permeability hyperpolarizes the membrane, which reduces the frequency of heart muscle contraction.

TLS Online TPP Program

#Id: 9082

#XL - T Zoology

TLS Online TPP Program

#Id: 9083

#XL - T Zoology

Cholera toxin, secreted by Vibrio cholerae in the intestine of an infected person, is a heterodimeric protein (AB).