3FGH

Human mitochondrial transcription factor A box B

Summary for 3FGH

• Entry DOI: 10.2210/pdb3fgh/pdb
• Descriptor: Transcription factor A, mitochondrial, CADMIUM ION, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: hmg domain, mitochondrial transcription, activator, dna-binding, mitochondrion, phosphoprotein, polymorphism, transcription, transcription regulation, transit peptide
• Biological source: Homo sapiens (man)
• Cellular location: Mitochondrion: Q00059
• Total number of polymer chains: 1
• Total formula weight: 8356.61

Authors

Gangelhoff, T.A.,Mungalachetty, P.,Nix, J.,Churchill, M.E.A. (deposition date: 2008-12-06, release date: 2009-04-07, Last modification date: 2024-02-21)

Primary citation

Gangelhoff, T.A.,Mungalachetty, P.S.,Nix, J.C.,Churchill, M.E.
Structural analysis and DNA binding of the HMG domains of the human mitochondrial transcription factor A
Nucleic Acids Res., 37:3153-3164, 2009

PubMed Abstract: The mitochondrial transcription factor A (mtTFA) is central to assembly and initiation of the mitochondrial transcription complex. Human mtTFA (h-mtTFA) is a dual high mobility group box (HMGB) protein that binds site-specifically to the mitochondrial genome and demarcates the promoters for recruitment of h-mtTFB1, h-mtTFB2 and the mitochondrial RNA polymerase. The stoichiometry of h-mtTFA was found to be a monomer in the absence of DNA, whereas it formed a dimer in the complex with the light strand promoter (LSP) DNA. Each of the HMG boxes and the C-terminal tail were evaluated for their ability to bind to the LSP DNA. Removal of the C-terminal tail only slightly decreased nonsequence specific DNA binding, and box A, but not box B, was capable of binding to the LSP DNA. The X-ray crystal structure of h-mtTFA box B, at 1.35 A resolution, revealed the features of a noncanonical HMG box. Interactions of box B with other regions of h-mtTFA were observed. Together, these results provide an explanation for the unusual DNA-binding properties of box B and suggest possible roles for this domain in transcription complex assembly.

PubMed: 19304746
DOI: 10.1093/nar/gkp157

Experimental method

X-RAY DIFFRACTION (1.35 Å)