Fig. 1.

Analysis of spermatozoa for DNA integrity and the capacity of fertilization. (a) Spermatozoa were stained with the TUNEL kit. Green signals show TUNEL-positive cells. (b) Chromomycin A3 staining was applied to evaluate sperm DNA integrity. Spermatozoa with low DNA integrity are observed relatively brighter green, as CMA3 binds to unpacked guanine bases. (c) Green signals indicating anti-PLC-ζ1 protein was observed in different localizations in the spermatozoa. (d) Izumo-1 protein (green signals) was detected particularly in peri-acrosomal or neck locations. Red signals: sperm DNA with 7-AAD. Scale bar: 5 μm