Binding of KLF1 to the PKLR gene. (top) a representation of the PKLR gene structure including the start of the erythroid (E)-specific transcript (dark gray) and the liver (L)-specific first exon in light gray. (bottom) KLF1 binding and DNase I hypersensitive sites in cultured human erythroid progenitors (EP), K562; erythroleukemia cell line, HepG2; and liver cells line, as indicated.