Figure 1.

RNA synthesis in mitochondrial fractions. Run-on transcription in isolated mitochondria (lane 1), lysed mitochondria (lane 2), cleared mitochondrial lysate (lane 3), pooled TECs (lane 4) and the cleared supernatant from unlysed mitochondria (lane 5) was assayed as described in Materials and Methods. Note that the mito S130 sample (lane 5) represents the amount of RNA synthesized in a transcription reaction that had been scaled up ten-fold relative to the samples in lanes 1–4, supporting the conclusion that the clearing step is sufficient to pellet all unlysed mitochondria.