UAS regulatory sequences drive expression of yki which contains mutations in both WW domains.
ykiWW12.UAS/Scer\GAL4GMR.PF fails to rescue ykiB5
Expression of ykiWW12.Scer\UAS under the control of Scer\GAL4GMR.PF fails to rescue the growth defect seen in ykiB5 mutant clones.