The N-terminal domain of the TFIIH basal transcription factor complex p62 subunit (BTF2-p62) forms an interaction with the 3' endonuclease XPG, which is essential for activity. The 3' endonuclease XPG is a major component of the nucleotide excision repair machinery. The structure of the N-terminal domain reveals that it adopts a pleckstrin homology (PH) fold [1,2]. This PH-type domain has been shown to bind to a mono-phosphorylated inositide [2].

1: TFIIH contains a PH domain involved in DNA nucleotide excision repair. Gervais V, Lamour V, Jawhari A, Frindel F, Wasielewski E, Dubaele S, Egly JM, Thierry JC, Kieffer B, Poterszman A; Nat Struct Mol Biol. 2004;11:616-622. PMID:15195146

2: NMR structure of the amino-terminal domain from the Tfb1 subunit of TFIIH and characterization of its phosphoinositide and VP16 binding sites. Di Lello P, Nguyen BD, Jones TN, Potempa K, Kobor MS, Legault P, Omichinski JG; Biochemistry. 2005;44:7678-7686. PMID:15909982