FIGURE LEGENDS
Figure 1. Three heterozygous mutations in SLC26A8 were identified in three infertile patients. Pedigrees of three families with heterozygous variants in SLC26A8 . The c.1570_1571del mutation was exhibited by the dotted triangle in family A. The c.2191G>A mutation was exhibited by the dotted box in family B. The c.306del mutation was exhibited by the dotted triangle in family C.
Figure 2. The teratozoospermia phenotype of the three patients.(a) The Concentrations Papanicolaou staining of sperm in the three patients and normal control. The sperm malformation of pyriform heads, round-heads, and coiled-tail were observed in the three patients. (b) Detailed defects in sperm head and flagella were observed in the patients by SEM (scale bars, 5 µm). (c) The anomaly head and flagellum as well as abnormal organized mitochondria of sperm from the three individuals, compared with the normal control by TEM. (scale bars, 100 nm). ODF: outer dense fiber; OD: peripheral microtubule doublets; CP: central microtubules.
Figure 3. The expression analysis of the three heterozygousSLC26A8 mutations in transfected cells and sperm from the patients. (a) The western blotting analysis of SLC26A8 expression in cells transfected with plasmids carrying variants of p.A524*, p.V731I, and p.G103Afs*9. (b) The SLC26A8 levels in sperm lysates of patients and control. The SLC26A8 protein was present in the three individuals and normal control without distinction. (c) The immunofluorescence results showed no significant difference in the SLC26A8 expression of the sperm between three individuals and normal control.
Figure 4. The expression of SLC26A8 in human and mouse testes.(a) Representative images of testicular tubules in a mouse showing that SLC26A8 is principally localized to the cytoplasm of different stages of spermatids (scale bar, 5 μm; red, SLC26A8; blue, DAPI). (b) SLC26A8 was detected in the nucleus and cytoplasm of germ cells at different stages (scale bar, 5 μm; red, SLC26A8; blue, DAPI). (c) Immunofluorescence staining indicated that SLC26A8 was primarily expressed in the head and cilia in human spermatogenic cells (scale bar, 5 μm; red, PNA; green, SLC26A8; blue, DAPI).
Table 1. Semen and variant analysis in the three patients harboring heterozygous SLC26A8 mutations.