Figure 1:

A. Upper panel: 3’-phosphatase activity of PNKP in the mitochondrial extract (250 ng) of frontal cortex from healthy normal control (lanes 2-5) vs. age-matched HD patients (lanes 6-9) measured by the release of free phosphate from a radiolabeled 3’-phosphorylated substrate. Lane 1: substrate only. Lane 10: Purified PNKP (2 ng). S: Substrate and P: Released phosphate. Lower panel: Quantitation of the % released phosphate in the indicated lanes (n=3); error bars represent mean ± SD. ***P<0.005 between Control vs. HD patient. B. Bar diagram represents mtROS level as relative fluorescence intensity with healthy control arbitrarily chosen as unity (n=14; ***P<0.005). C. Upper panel: Representative agarose gel image of long (LA) and short (SA) amplicon of the mitochondrial fragment from genomic DNA of postmortem frontal cortex of age-matched healthy normal (control) (lanes 1-4) and HD patients (lanes 5-8). Lower panel: The normalized relative band intensities are represented in the bar diagram with one control sample arbitrarily set as 100. The damage accumulation in HD patients significantly increased (***P < 0.005; **P < 0.01).