UAS regulatory sequences drive expression of a mutated form of Grip in which the conserved R/KxxxGLGF carboxylate binding loop motifs of domains PDZD 1, 2 and 3 have each been mutated to AxxxGAGF.
Larvae expressing Gripx1,2,3.Scer\UAS under the control of Scer\GAL4twi.PG show ectopic lateral transverse muscle projections and mild ventrolateral muscle defects.