UAS regulatory sequences drive expression of the full-length Myo31DF protein tagged at the C-terminal end with mRFP1.

Expression of Myo31DF^{Scer\UAS.T:Disc\RFP-mRFP} under the control of Scer\GAL4^byn-Gal4 rescues the inverse left-right asymmetry in the hindgut positioning characteristic for Myo31DF^L152 homozygous embryos.

Induction of somatic clones of 'rescued cells', i.e. cells expressing Myo31DF^{Scer\UAS.T:Disc\RFP-mRFP} under the control of Scer\GAL4^Act5C.PT (using the Aloxg-Gal4 system) in the Myo31DF^L152 homozygote mutant background, significantly reduces the frequency of embryos with the reversed LR hindgut asymmetry as compared to non-mosaic Myo31DF^L152 mutants. The percentage of 'rescued cells' in the epithelium positively correlates with normal hindgut laterality and normal left-handed hindgut rotation occurs when about 35% of the cells in the epithelium are the 'rescued cells'. The mosaic hindgut epithelium also does not show a prominent cell-shape chirality observed either in the wild-type embryos (dextral planar cell chirality) or in the non-mosaic Myo31DF^L152 mutants (sinistral chirality) but the hindgut still undergoes a complete 90[o] left-handed rotation in majority of embryos. In the mosaic embryos, apical cell boundaries between two 'rescued cells' (R-R boundary) show on average significant dextral cell-shape chirality whereas in the 'rescued cell'- mutant cell neighbor pairs (R-M boundary) or between two mutant cells (M-M boundary) there is no significant difference between the frequency of apical cell boundaries falling in the -90[o] to 0[o] angle bin and the 90[o] to 0[o] bin. The dextral cell-shape chirality of 'rescued cells' is only evident if the cells are part of a larger clone of cells but is suppressed in smaller clones of up to 8 cells. The average length of R-R and R-M cell boundaries before and after hindgut rotation does not significantly change but the M-M boundaries are elongated after rotation.