General transcription factor IIH subunit 5 is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''GTF2H5''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
Function
The ''GTF2H5(TTDA)'' gene encodes a small (71 amino acid) protein that stabilizes the multi-subunit
transcription repair factor IIH(TFIIH). TFIIH plays a key role in a major
DNA repair
DNA repair is a collection of processes by which a cell (biology), cell identifies and corrects damage to the DNA molecules that encode its genome. A weakened capacity for DNA repair is a risk factor for the development of cancer. DNA is cons ...
process,
nucleotide excision repair (NER), by opening the DNA double helix after the initial recognition of damage in one strand. This step is followed by excision of the damaged region to generate a single-strand gap, and then repair synthesis, using the undamaged strand as template, to accurately fill in the gap. Disruption of the ''GTF2H5(TTDA)'' gene in a
knockout mouse-model completely inactivates NER.
In humans, mutation in any one of four genes can give rise to the
trichothiodystrophy phenotype. These genes are ''TTDN1'', ''
XPB'', ''
XPD'' and ''GTF2H5(TTDA)''.
Interactions
GTF2H5 has been shown to
interact with
GTF2H2 and
XPB.
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]
References
Further reading
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