III.    Heptahelical-transmembrane receptors (GPCR) and their
heterotrimeric G-proteins are the targets of approximately fifty
percent (50%) of commercial drugs on today’s market.   After leaving
the JHU program (successfully we hope) you land a job at a
pharmaceutical company making more money than your former teachers. 
Your lab chief assigns a drug under development to you, and asks that
you:

 (A) Determine the receptor for the drug, and (B) which signaling
pathways it targets.   The drug itself is a short peptide that blocks
the action of a naturally expressed neuro-peptide by binding to the
receptor but not stimulating it.   When given to mice, the drug
significantly increases the ability of the mouse to resist the actions
of seizure inducing drugs.   These two facts lead you to conclude the
receptor is probably a GPCR.  Remember the structural traits of this
system, and describe an experimental protocol to answer the questions
posed.  Previous scientists (whom you are replacing since they were
unable to successfully finish the project) tried but failed to isolate

Dear jimmy1978-ga,

Your question fascinates me.  I have interests in signal transduction.
 However, from the wording I suspect that people at Johns Hopkins
University may be better qualified to answer this than I.  So if it's
all right, I will forward this to some of my friends who teach there.

Good luck!