Fig. 7. Unc-GFP is first localized in G2 spermatocytes. Merged phase-contrast and fluorescence image of spermatocytes from larval testes expressing UNC-GFP. (A) Timeline of spermatocyte development. (B-G) Polar, apolar and mature spermatocytes in a wild-type testis. UNC-GFP is first localized in polar spermatocytes to four paired dots (B,C; enlarged in inset); the labeled structures are larger in apolar spermatocytes (D,E) and migrate to the cell periphery in mature cells (F,G). (H,I) Arrested gonial cells in bgcn mutant testis: no localized Unc-GFP is detectable. (J,K) Arrested primary spermatocytes in an sa mutant: paired UNC-GFP labeled structures are smaller than those in wild-type cells at a comparable stage. Scale bar: 20 µm.