FIGURE 5.

Distribution of hGDH2 and hGDH1 in mitochondrial and cytosolic fractions prepared from human testis. The mitochondrial fraction was isolated using the Ficoll method (see “Experimental Procedures”). Equal protein amounts of whole lysate and mitochondrial and cytosolic fractions were electrophoresed on an 8.5% SDS-polyacrylamide gel, and immunoblotting was performed using the anti-hGDH2 antibody (A) and the non-discriminating (Non-discr.) anti-GDH antibody (B). Actin (C) and manganese superoxide dismutase (MnSOD; D), visualized by the respective antibodies, served as cytosolic and mitochondrial markers, respectively. Both hGDH1 and hGDH2 were enriched in the mitochondrial fraction, whereas the cytosolic fraction was essentially devoid of GDH immunoreactivity. These immunoblotting data agree with the results of GDH activity assays using these fractions (data not shown).