Subcellular localization of epitope-tagged RNase H1.
A, immunocytochemistry of cells transiently transfected with RNase H1-V5, probed for the V5 epitope tag (red), Cox4 (green), and DAPI (blue), showing examples of the three types of intracellular distribution of V5-tagged RNase H1: nucleus and mitochondria (i), mitochondria only (ii), and nucleus only (iii). B, subcellular distribution of RNase H1-V5 in 100 transfected cells as indicated (mean of three experiments, error bars denote S.D.). C, Western blots of subcellular fractions from cells transfected with RNase H1-V5, highly enriched for nuclei (nuc) or mitochondria (mt) as indicated, probed simultaneously for V5 and for the markers indicated. M, molecular mass markers.