Figure 3

Increased transcription of the matrix metalloproteinase 1 (MMP1) gene promoter in xeroderma pigmentosum group C (XP-C) fibroblasts depends on the proximal AP-1 sequence. (a) mRNA levels of MMP1, 2, 3 and TIMP1 in control (wild-type (WT): FMD, HF29 and HF84) and XP-C (XP148, XP433 and XP521) fibroblasts measured by real-time quantitative PCR. Amount of MMP1 mRNA is significantly higher in XP-C than in control fibroblasts, ^*P<0.05. (b) Relative transcriptional activity of the full-length (4.4 kb) MMP1 promoter (pCollLUC −4400) and (c) of the proximal 136 bp 5′-regulatory region spanning from nucleotide −73 to +63 of the MMP1 gene (pCollCAT-73). As illustrated, full-length and short MMP1 promoter constructs contain four and one AP-1-binding sequences, respectively. Experiments were repeated at least two times in triplicates. Data are represented as the mean±s.d. of triplicates. The mean transcriptional activities in WT and XP-C fibroblasts strains are indicated as a thin and a large dotted line, respectively. ^*P<0.05; a.u., arbitrary units.