Fig. 1: Mitochondrial and axonemal abnormalities lead to abnormal spermatid elongation in Grip163^Δ11 mutant.

a Schematic representation of Drosophila spermatogenesis stages in the testis, highlighting the major cellular organelles (bb basal body, n nucleus, nb nebenkern, a acrosome, ax axoneme and cytoskeletal structures (ic investment cone) of the secondary spermatocyte, round spermatids and the elongated spermatid cyst. b, c Microtubules are visualized with the β2tub-GFP transgene (green), while the nuclei stained with DAPI (blue) in WT b and Grip163^Δ11 mutant spermatids (c) Elongated cysts are present both in WT and Grip163^Δ11, however, the seminal vesicle (dashed lines) of Grip163^Δ11 mutant does not contain β2tub-GFP positive mature sperms. d, e The individualization complexes (IC) were stained with Phalloidin (red), ICs are formed normally (arrows) in WT, (c) and missing in Grip163^Δ11 mutant (e). f, g Fully developed axonemes are visualized by Axo49 tubulin antibody (red) and elongated mitochondria are with DJ-GFP transgene (green) both in the testis and seminal vesicle (dashed line). Elongated polyglycylated axonemes and mitochondria were shorter in Grip163^Δ11 mutant and the seminal vesicle was empty (dashed line) (g) compared to the WT (f). h Boxplot shows the length of AXO49 positive cysts in WT and Grip163^Δ11 mutant. (WT n_testis = 12, Grip163^Δ11 n_testis = 22, WT n_measurement = 36, Grip163^Δ11n_measurement = 64) Statistical significance was tested by one-way ANOVA. (scale bars: 50 μm).