Receptor protection experiments

Application of irreversible antagonists (receptor protection experiments, attempted... 

Another test for specific labeling is to determine whether the ligand binding site is blocked. But, as 1 pointed out in the discussion of photoinactivation experiments, there are several other possible causes of apparent binding site occupation besides the covalent attachment of a ligand. It has also been noted that specific labeling as defined by a protection experiment may not always yield a blocked receptor when the photoaffinity label is a macromolecule. When sodium channels in tissue culture cells were labeled... 

Sassone-Corsi In the experiment you showed it is clear that in all those receptors there is extensive alternative splicing. In an RNAse protection assay, picking the probe is crucial. 

---