slbo open reading frame from P{Pw15} is replaced by a fragment carrying slbo fused to the Scer\GAL4 activation domain (amino acids 851 to 881) at amino acid 318.
slboGAL4S fails to rescue slbounspecified
P{GAL4S/Dm} cannot rescue slbo- flies (between 3% and less than 1% slbo- flies are rescued).