Defective <i>in vivo</i> recruitment of CAK to DNA damage sites in severe XP-G and XP-G/CS cells.

<p>(<b>A</b>) Schematic representation of wild-type and mutant XPG proteins expressed in XPCS1LV, XPCS2LV and XP3BR fibroblasts. N (orange) and I (red) boxes represent the conserved regions essential for the nuclease activity. NLS (blue) and C (cyan) boxes are nuclear localization signal and conserved C-terminal regions, respectively. The (violet) boxes indicate non-XPG residues in XPB3BR cells. The numbers indicate total amino acids in the XPG protein. (<b>B–D</b>) Recruitment of core TFIIH (as depicted by XPB, p62 and XPD), CAK (as depicted by MAT1) and XPG proteins to DNA damage sites. Cells were locally irradiated with 100 J/m² UV, allowed to repair DNA for 0.1 h and then processed as described for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0011007#pone-0011007-g001" target="_blank">Figure 1A</a>. (<b>E and F</b>) The repair factor recruitment was examined at 0.1 and 24 h post local UV irradiation, respectively. The number of foci/100 cells was calculated based on counting the foci in at least 100 nuclei from five different microscopic fields. Bars indicate mean ± S.E. Symbols * and # indicate significant difference (p<0.05) from NHF and XP3BR cells, respectively.