Format

Send to

Choose Destination
Nat Struct Mol Biol. 2011 Oct 30;18(11):1281-9. doi: 10.1038/nsmb.2160.

Human mitochondrial transcription factor A induces a U-turn structure in the light strand promoter.

Author information

1
Department of Structural Biology, Molecular Biology Institute of Barcelona (CSIC), Barcelona, Spain.

Erratum in

  • Nat Struct Mol Biol. 2012 Mar;19(3):364.

Abstract

Human mitochondrial transcription factor A, TFAM, is essential for mitochondrial DNA packaging and maintenance and also has a crucial role in transcription. Crystallographic analysis of TFAM in complex with an oligonucleotide containing the mitochondrial light strand promoter (LSP) revealed two high-mobility group (HMG) protein domains that, through different DNA recognition properties, intercalate residues at two inverted DNA motifs. This induced an overall DNA bend of ~180°, stabilized by the interdomain linker. This U-turn allows the TFAM C-terminal tail, which recruits the transcription machinery, to approach the initiation site, despite contacting a distant DNA sequence. We also ascertained that structured protein regions contacting DNA in the crystal were highly flexible in solution in the absence of DNA. Our data suggest that TFAM bends LSP to create an optimal DNA arrangement for transcriptional initiation while facilitating DNA compaction elsewhere in the genome.

Comment in

PMID:
22037172
DOI:
10.1038/nsmb.2160
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center