temperature

Does anyone know anything about changing growth temperature for yeast two hybrid analysis to ensure temperature is appropriate for protein conformation? I am looking at connections between full length plant flowering proteins which are orthologous to proteins shown act together in 3 other diverse angiosperms (Monocots + Dicots) - so I would be surprised if they didn't interact in my species, but at standard yeast growth conditions of 30'C (manufacturer's instructions) I get no evidence of interaction from -HIS+3AT, Xgal assay, -URA. I've read articles where people have done yeast two hybrid tests at 25'C or 22'C to ensure appropriate temperature for protein conformation.
Are these temperature choices usually based on optimal growth conditions for the plant species the proteins studied are from?

"Are these temperature choices usually based on optimal growth conditions for the plant species the proteins studied are from?"

Mostly.

Also, you have to consider that if your proteins are large they might have additional requirements for proper folding and interactions...