Fig. 7. MATH1/E47 heterodimers bind an E-box-containing sequence flanking Hes5. The DNA-binding activity of MATH1 was examined by electrophoretic mobility shift assay with or without E47. ³²P-labeled E-box-containing targets were from asense, shown before to bind MATH1 (Akazawa et al., 1995) (A) and Hes5 (B). MATH1 binds both targets in its heterodimer, but not monomeric, form.