Use of nuclear hormone receptors

A method for determining whether a compound that has an EC50 value greater than 500 nM in a homogenous time-resolved fluorescence assay inhibits meiosis activating activity, said method comprising testing the effect of said compound on germinal vesicle breakdown (GVBD) in the presence of 4,4-dimethyl-5α-cholesta-8,14,24-triene-3β-ol (FF-MAS) in an oocyte maturation assay, whereby measurement of a GVBD value for said compound in said oocyte maturation assay that is less than the GVBD value measured in said oocyte maturation assay in the absence of said compound indicates that said compound inhibits meiosis activating activity.

A method for detecting the presence of an antagonist of a meiotic regulating substance (MAS), said method comprising the steps of a) exposing a compound in the presence of a MAS agonist to a nuclear hormone receptor (NR) coupled to a response pathway under conditions and for a time sufficient to allow binding of the compound to the NR and an associated response through the pathway;

• and b) detecting a reduction in the stimulation of the response pathway resulting from the binding of the compound to the NR, relative to the stimulation of the response pathway by the MAS agonist alone and therefrom determining the presence of a MAS antagonist.

A method for detecting the presence of an agonist of a meiotic regulating substance (MAS), said method comprising the steps of a) exposing a compound to a nuclear hormone receptor (NR) coupled to a response pathway under conditions and for a time sufficient to allow binding of the compound to the NR and an associated response through the pathway;

• and b) detecting a stimulation of the response pathway resulting from the binding of the compound to the NR, relative to the stimulation of the response pathway detected in the absence of said compound and therefrom determining the presence of a MAS agonist.

A method of screening for agonists or antagonists of 4,4-dimethyl-5α-cholesta-8,14,24-triene-3β-ol (FF-MAS) activity, the method comprising incubating a nuclear hormone receptor (NR) with a substance suspected to be an agonist or antagonist of FF-MAS, and subsequently with FF-MAS or an analogue thereof, and detecting any effect of binding of FF-MAS or the analogue to meiotic regulating substance (MAS) receptor.

A method of screening for agonists or antagonists of 4,4-dimethyl-5α-cholesta-8,14,24-triene-3β-ol (FF-MAS) activity, the method comprising incubating FF-MAS or an analogue thereof with a substance suspected to be an agonist or antagonist of activity of FF-MAS and subsequently with a nuclear hormone receptor (NR), and detecting any effect of binding of FF-MAS or the analogue to the NR.