Measuring Receptor Homodimerization

A method of detecting homodimers of membrane-associated analytes on a cell membrane, the method comprising the steps of:

• providing a binding compound specific for a membrane-associated analyte forming a homodimer, the binding compound having one or more molecular tags each attached thereto by a cleavable linkage, the one or more molecular tags each having a different separation characteristic;
• providing a cleaving probe specific for the membrane-associated analyte, the cleaving probe having a cleavage-inducing moiety with an effective proximity to the cleavable linkage, and the cleaving probe and the binding compound being selected such that only one of either the cleaving probe or the binding composition can specifically bind to the same membrane-associated analyte at a time;
• combining the cleaving probe, the binding compound, and the cell membrane such that the cleaving probe and the binding compound specifically bind to membrane-associated analytes and such that cleavable linkages of the binding compound are within the effective proximity of the cleavage-inducing moiety whenever a homodimer is present and the cleaving probe and the binding compound specifically bind to different membrane-associated analytes thereof, so that molecular tags are released;
• and
• separating and identifying the released molecular tags to determine the presence or absence or the amount of homodimer in the cell membrane.