Mutations in mitochondrial DNA causing tubulointerstitial kidney disease
Fig 5
m.547A>T impairs mitochondrial heavy strand promoter activity.
(A) In vitro transcription with purified mitochondrial transcription factors and a dual promoter construct containing the heavy (HSP) and light strand promoter (LSP) was used to assess the effect of the m.547A>T substitution. The linear template results in run off (RO) transcripts of 190 nucleotides (nt) from the HSP and 90 nt from the LSP. (B) Metabolically labelled transcripts from wild type (wt) and m.547A>T variant promoter (A547T) were analysed by autoradiography. (C) Analysis of relative band intensities of (B) shows a significant reduction of HSP activity in the presence of the m.547A>T substitution (p = 0.0014). The experiment was performed three times yielding the same result.