Figure 3.

Expression of germ cell-specific isoforms of HK1 in sperm. Cauda epididymal mouse sperm were fractionated, and proteins from whole sperm extracts (20 μg, labeled “sperm”), a 10,000 × g sperm pellet (40 μg, labeled “P₁₀”), a 100,000 × g sperm supernatant (20 μg, labeled “S₁₀₀”), and a 100,000 × g sperm pellet (40 μg, labeled “P₁₀₀”) were separated by SDS-PAGE and subjected to immunoblotting. (A) α-sa immune and α-sa preimmune antisera. (B) α-sb immune and α-sb preimmune antisera. (C) α-gcs immune and α-gcs preimmune antisera. In each case, the appropriate purified recombinant protein was used as a positive control. (D) Recognition of endogenous HK1-sc was demonstrated to be specific because immunoreactivity was lost when the α-gcs antiserum was preabsorbed with the peptide against which it was made.