Carries 12 single-base mutation, all within the GLS of grk. All 12 mutations target wobble nucleotides and preserve the encoded protein sequence. Five of the mutations disrupt the predicted base pairing pattern of the GLS.

grk^GLS.mut partially rescues grk^ΔFRT

grk^GLS.mut fails to rescue the female sterility of grk^ΔFRT mutants. The grk^GLS.mut transgene exhibits no or only weak rescue of the dorsoventral patterning defects of grk^ΔFRT flies. Approximately half of the recovered eggs are fully ventralised and similar to those produced by grk^ΔFRT females. The remaining recovered eggs are strongly ventralised, containing a single small appendage on the dorsal midline. The grk^GLS.mut transgene exhibit incomplete rescue of the anteroposterior patterning defects of grk^ΔFRT flies.Thus while nuclear migration is consistently delayed and sometimes incomplete, most stage 8 and older egg chambers contain a correctly positioned nucleus. grk^GLS.mut rescues the compound egg chamber phenotype of grk^ΔFRT.