Solution structure of the p8 TFIIH subunit
[TF2H5_HUMAN] Defects in GTF2H5 are a cause of trichothiodystrophy photosensitive (TTDP) [MIM:601675]. TTDP is an autosomal recessive disease characterized by sulfur-deficient brittle hair and nails, ichthyosis, mental retardation, impaired sexual development, abnormal facies and cutaneous photosensitivity correlated with a nucleotide excision repair (NER) defect. Neonates with trichothiodystrophy and ichthyosis are usually born with a collodion membrane. The severity of the ichthyosis after the membrane is shed is variable, ranging from a mild to severe lamellar ichthyotic phenotype. There are no reports of skin cancer associated with TTDP.
[TF2H5_HUMAN] Component of the TFIIH basal transcription factor involved in nucleotide excision repair (NER) of DNA and, when complexed to CAK, in RNA transcription by RNA polymerase II. Necessary for the stability of the TFIIH complex and for the presence of normal levels of TFIIH in the cell.
Publication Abstract from PubMed
Trichothiodystrophy (TTD) is a rare hereditary multi-system disorder associated with defects in nucleotide excision repair (NER) and transcription as consequences of mutations in XPB, XPD and p8/TTD-A subunits of transcription factor IIH (TFIIH). Here, we report the solution structure of the p8/TTD-A protein, a small alpha/beta protein built around an antiparallel beta-sheet that forms a homodimer with an extended interface. In order to characterize the dimer interface, we have introduced a mutation at position 44, which destabilizes the dimeric form of the protein. We have shown that this mutation has no effect on the intrinsic ability of p8/TTD-A to stimulate NER in vitro, but affects the capacity of p8/TTD-A to restore TFIIH concentration in TTD-A fibroblasts. Point mutations found in TTD-A patients are discussed on the basis of the present structure.
Solution structure and self-association properties of the p8 TFIIH subunit responsible for trichothiodystrophy.,Vitorino M, Coin F, Zlobinskaya O, Atkinson RA, Moras D, Egly JM, Poterszman A, Kieffer B J Mol Biol. 2007 Apr 27;368(2):473-80. Epub 2007 Feb 20. PMID:17350038
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.