Question

What would happen if the intracellular domain of a cell-surface receptor was switched with the domain from another receptor?

a) The receptor would lose its ability to bind ligands
b) The receptor would exhibit constitutive activation
c) The receptor would become internalized
d) The receptor would lose its specificity for ligands

Answer 1

If the intracellular domain of a cell-surface receptor is switched with the domain from another receptor, the receptor could lose its specificity for ligands, lose its ability to bind ligands, or exhibit constitutive activation.

Step-by-step explanation:

When the intracellular domain of a cell-surface receptor is switched with the domain from another receptor, several outcomes can occur:

1. The receptor would lose its specificity for ligands: The ligand-binding domain of a receptor is responsible for recognizing and binding specific ligands. If the intracellular domain is switched, the receptor may not be able to interact properly with its ligand, leading to a loss of specificity.
2. The receptor would lose its ability to bind ligands: If the intracellular domain does not have the necessary components for ligand binding, the receptor may not be able to effectively bind ligands and initiate a signaling cascade.
3. The receptor would exhibit constitutive activation: In some cases, swapping intracellular domains can result in the receptor being constantly active, even in the absence of ligand binding. This can lead to abnormal signaling and cellular responses.