Fig. 6. achi/vis phenotype. (A-D) The late stage primary spermatocyte chromatin phenotype. (A) Phase contrast image of wild-type stage 5 primary spermatocyte. Arrow indicates nucleolus, arrowhead indicates Y-chromosome loops. (B) DAPI labelling reveals the chromatin peripherally located against the nuclear membrane. (C) Primary spermatocyte from Df(2R)achi¹ homozygote testis demonstrating stage 5 characteristics: nucleolus (arrow), Y-loops (arrowhead) and intact nuclear membrane. (D) DAPI labelling of cell in C reveals chromatin clumps reminiscent of meiotic division stages (Cenci et al., 1994). (E-G) Anti-histone labelling reveals the chromatin configuration in stage 5 primary spermatocytes in wild type (E), Df(2R)achi¹ (F) and aly (G). The chromatin morphologies in F and G are clearly distinct; the aly configuration resembles that of wild type, but is more diffuse. (H-K) Expression and localisation of Aly and Comr in achi^Z3922 vis^Z3922 homozygote testes. (H) Wild type, anti-Aly; (I) achi^Z3922 vis^Z3922, anti-Aly, (J) wild type, anti-Comr, (K) achi^Z3922 vis^Z3922, anti-Comr. Aly and Comr are present in the nucleus in achi^Z3922 vis^Z3922 testes but the localisation appears more diffuse than in the wild type.