UAS regulatory sequences (from the pVALIUM22 vector) drive expression of the long osk isoform with a deletion of the SGNH domain (amino acids 410 to the C-terminal end of the coding sequence are deleted), tagged at the C-terminal end with mCherry, Tag:FLAG and Tag:HA. bcd 3'UTR sequences are present, resulting in localization of the mRNA to the anterior region of the early embryo.