FIG. 4.

Localization of mitochondria in spermatozoa by MitoTrack staining. (A) Spermatozoa from wild-type mice showing fluorescence in the middle piece. (B) Spermatozoa from nectin-2^−/− mice with fluorescence in the head and in a bulge located in the middle piece. (C) Spermatozoa from nectin-2^−/− mice exhibiting fluorescence only in the head. (D) Spermatozoa from nectin-2^−/− mice. One cell has fluorescence only in the middle piece, and the other has fluorescence in both the head and the middle piece. Magnifications, ×3,080 (A) and ×1,540 (B to D).