Amino Acid Effects.

Well, what have you gotten thus far? We should build on each other's knowledge.

The structural elements involved in regulation or receptor activity are generally located in the cytosolic domain. There are, above all, protein sequences that permit phosphorylation of the receptor by protein kinases. Phosphorylation at Ser/Thr or Tyr residues of the cytosolic domain may lead to inactivation or activation of the receptor and thus weaken or strength signal transmission. In this way, Ser/Thr-phosphorylation is used in the process of internalization of receptors in order to remove the receptor from circulation after it has been activated. The protein kinases involved are often part of other signaling pathways and can link the activity of the transmembrane receptors to other signal networks.

Targeted degradation of receptors is another means of regulating receptor activity. Signals for ubiquitination and subsequent degradation in the proteosome has been identify in the cytosolic domain of transmembrane receptors. A major mechanism of targeting transmembrane receptors fro proteolysis uses signal-directed phosphorylation of the cytosolic domain.