Fig. 7. vls is required for normal accumulation of Osk isoforms. Western blots of the indicated ovary extracts probed with -Osk antibodies. Loading of approximately equal amounts of proteins shows that vls^null ovaries contain only very little Osk compared with wild type (OreR; left blot). -Osk antibodies recognize the Long isoform of Osk, as well as the hyperphosphorylated (57 kDa) and hypophosphorylated (55 kDa) forms of Short Osk (arrows). For the blot on the right, about ten times as much protein extracts were loaded onto the vls^null lane compared with the loading for the OreR lane. Ponceau staining of the membrane (Ponc., left blot) and reprobing of the blot with -Tubulin antibodies (right blot) were used as loading controls.