An αTub84B promoter drives expression of shg in which a conserved triplet of Gly resides in the juxtamembrane region has been mutated to a triplet of Ala residues (the equivalent mutation in the human ortholog disrupts the interaction with p120ctn but does not affect the interaction with &bgr-catenin).
Follicle cells expressing shgGGG-AAA.αTub84B do not sort away from cells also expressing wild-type shg.
shgGGG-AAA.αTub84B partially rescues shg1
shgGGG-AAA.αTub84B partially rescues shgR69
Expression of shgGGG-AAA.αTub84B in shg1 mutant border cells or nurse cells can rescue the border cell migration phenotype seen in these cells. Expression of shgGGG-AAA.αTub84B rescues the head and ventral epidermis phenotypes seen in homozygous shg1 embryos. 10-25% of homozygous shg1 carrying shgGGG-AAA.αTub84B hatch, and the resulting larvae look normal. When shgGGG-AAA.αTub84B is expressed in shgR69 homozygotes a few percent of the mutants are rescued to adulthood.