FIG. 6.

Round cells found in Cstf2t^−/− caudal epididymal fluid showed DNA contents and remnant tail structures. The same representative round cells isolated from Cstf2t^−/− caudal epididymal fluid is showed in phase contrast (A), labeled with propidium iodide (B), and labeled with SYBR-14 (C). Examples of spermatogenic cells in phase contrast with a round head (D–E) and including externally coiled flagella (F) are also shown. Electron micrographic images of this deficient spermatogenic cells showing disorganized or missing internal structure indicated by an arrow (G) and coiled tail within the plasma membrane indicated by arrowheads (G and H) are shown as well. Original magnification ×96.