Figure 5.

Defects of mtDNA replication cause mtDNA deficiency during T cruzi infection. A, mtDNA content in T cruzi–infected human cardiomyocytes (a) and cardiac biopsies of chagasic patients (b) was determined by real-time PCR amplification of COI and 16S regions of mtDNA, normalized to 18S nuDNA. D-loop formation was assessed by measuring 7S RNA, normalized to mtDNA amount in infected cardiomyocytes (c). mtDNA replication was assessed by measuring the extension of 7S DNA beyond the D-loop (d). B, Real-time RT-PCR amplification of mRNA for PGC-1/NRF gene targets (SSBP1, POLG, PEO1, and TOP1mt) involved in mtDNA replication in T cruzi–infected cardiomyocytes. Statistical significance of data was analyzed as described in Figure 1. RT-PCR indicates reverse-transcription polymerase chain reaction; SSBP, single-stranded DNA-binding protein.