Figure 5. Identification of highly methylated binding sites for transcription factors in the LTBP4L and LTBP4S promoter.

In silico analysis of LTBP4 promoter sites identified a highly methylated binding site for GATA1 in the LTBP4L promoter of OE33 and KYSE180 cells. Highly methylated binding sites for SP1 and E2F4 are found in the LTBP4S promoter of both cell lines. A binding site for SMAD3 was identified nearby. The methylation status was analyzed by clonal bisulfite sequencing and at least ten clones were sequenced for each cell line. The percentage of methylation is visualized as pie chart. Exons are illustrated by black boxes and LTBP4S and LTBP4L promoters by red lines. The translation start sites are indicated (ATG). The dashed lines represent alternative splicing of LTBP4.