Figure 4. hTDP1 catalytic mutants increase stability of covalent enzyme-genomic DNA intermediates.
A. Band-depletion of stably transfected HEK293 cells. Immunoblot of total cell extracts treated with (+ nuclease) or without micrococcal nuclease. Two times more hTDP1H493N total cell extracts were loaded than other samples to emphasize band-depletion. B-C. Cell fractionation of the stably transfected HEK293 cells used in (A). B. Cytosolic/mitochondrial lysate fraction, and C. Nuclear fraction split in the nucleoplasm and genomic DNA. All samples were resolved via 12% SDS-PAGE and immunoblotted with anti-hTDP1 and anti-αTubulin (A-B); anti-hTDP1 and anti-Histone H3 (C).