TABLE 1.

PROS AND CONS OF USING YEAST TO STUDY NUCLEAR RECEPTORS

Yeast	Tissue Culture Cells
Ligand-dependent transactivation of nuclear receptors possible. Compounds that act as antagonists in tissue culture cells behave as partial agonists in yeast.	Cell and promoter selective agonist and antagonist function can be reconstructed.
Pure heterodimeric and multimeric interactions possible with nuclear receptors.	Not possible due to endogenous nuclear receptors.
Ligands are not metabolized.	Ligands are metabolized in mammalian cells.
Unique (simple) basal transcription context.	Physiological relevance of the unique context, depending upon the promoter and cell line.
Can produce large amounts of a receptor protein.	Incompatible with cell physiology.
Complementation cloning to discover novel orphans or partners (i.e., RIPs and TRIPs).	Not possible or very time consuming.
Stable transformants. HTS engine, parallel screens possible using robotics.	Transfection of DNA required. Data from stable cell lines may not be reliable.