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Initiation of mtDNA transcription is followed by pausing, and diverge across human cell types and during evolution

ABSTRACT: We analyzed nascent mtDNA-encoded RNA transcripts from GRO-seq and PRO-seq experiments in a collection of diverse human cell lines and Metazoan organisms. Accurate detection of human mtDNA transcription initiation sites (TIS) in the heavy and light strands revealed a novel transcription pausing site near the light strand TIS, upstream to the transcription-replication transition region, in conserved sequence block III (CSBIII). The transcription pausing index varied quantitatively among the cell lines. In addition to the human cell lines experiments, our experiments and analysis of non-human organisms enabled detection of previously unknown mtDNA TIS, pausing, and transcription termination sites with unprecedented accuracy. Whereas mammals (chimpanzee, rhesus macaque, rat, and mouse) showed a human-like mtDNA transcription pattern, the invertebrate pattern (Drosophila and C. elegans) profoundly diverged.

ORGANISM(S): Rattus norvegicus Mus musculus Pan troglodytes Homo sapiens Macaca mulatta Caenorhabditis elegans Drosophila melanogaster

PROVIDER: GSE85747 | GEO | 2016/09/30

SECONDARY ACCESSION(S): PRJNA339241

REPOSITORIES: GEO

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