Fig. 5. Western blot analysis of prt^gs mutant ovaries. Western blot of ovary extracts probed with the anti-OSK antibody. Wild type, prt^gs and Osk⁵⁴/Df stands for an OSK protein null combination (osk⁵⁴/Df(2)RPXT103). The bottom panel shows the same Western blot probed with anti -Tubulin antibody as a loading control. The molecular weight of the three OSK-specific bands long OSK (71 kDa), phosphorylated short OSK (57 kDa) and unphosphorylated short OSK (55 kDa) are indicated.