KCl-Dependent Release of Mitochondrial Membrane-Bound Arginase Appears to Be a Novel Variant of Arginase-II

Figure 3

Analysis of arginase isoforms in subcellular fraction of liver of Mus musculus. (a) Histogram represents activity of arginase in different subcellular fractions and (b) shows western blot analysis of cytosolic fraction, total mitochondria, mitochondrial matrix, and mitochondrial outer membrane fractions probed with anti-arginase-II, anti-arginase-I, anti-GAPDH, anti-β-actin, and anti-cytochrome C (from top to bottom). The mitochondrial arginase was not observed in cytosolic fraction, whereas it was detected in mitochondrial outer membrane fraction (KCl-treated fraction). The anti-arginase-I did not show cross reactivity with mitochondrial fractions as well as mitochondrial membrane-bound fraction. It clearly indicates that mitochondrial membrane-bound arginase is associated with mitochondrial arginase-II. C = cytosolic fraction, W1 = first wash of total mitochondrial fraction with homogenizing medium, W2 = second wash of total mitochondrial fraction with homogenizing medium, Mtm = mitochondrial matrix fraction (after KCl wash), Tmt = total mitochondrial fraction (before KCl treatment), and MtMb = mitochondrial outer membrane fraction (KCl-washed supernatant).The variant that is immunoreactive with anti-arginase-II.

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