| abstract |
The present invention provides transcriptional control regions, expression vectors comprising said regions, mammalian cells transformed to transcribe and express genes from said vectors, and various methods of assaying compounds for hormone agonist or antagonist activity, all based on discovery of response elements of the $g(b)-retinoic acid receptor and of the activation of said response elements in all mammalian cells without need to transform the cells to express the receptor independently of endogenous expression thereof. |