Different Classes Of Heterotrimeric G Proteins And Their Coupling Properties

Girk Channel Activation Receptors

The different classes of G proteins are defined by their sequence identity as well as their downstream effector coupling specificity. There are over 20 Ga-subunits known to date, and they are divided into four major Ga subfamilies. Because the coupling of the receptor to the different classes of G proteins specifies the signaling pathways that are activated, GPCRs are functionally classified according to their coupling specificity, such as Gs- or Gq-coupled receptors. Several recent reviews...