Positive control.

Interaction in vitro; bait produced as a recombinant fusion protein in bacterial system; prey produced and labeled by in vitro translation.

Source was yeast cell line; bait produced as transgenic fusion protein; prey produced as transgenic fusion protein (prey was previously cloned reagent).

Modified yeast two-hybrid system: The DNA binding moiety is a fragment of dl that includes the DNA binding and dimerization domain but lacks the transcriptional activation domain. It is thus unable to drive expression from a reporter on its own. The twi protein contains its own transcriptional activation domain but cannot bind to the reporter, so expression from the reporter when both dl and twi are present is taken as evidence of an interaction.

Source was yeast cell line; bait produced as transgenic fusion protein; prey produced as transgenic fusion protein (prey from embryo cDNA expression library).

Two-hybrid system: yeast LexA-BD/GAL4-AD