Fig. 7. NRL modulates CRX binding affinity to the rhodopsin proximal promoter.

A. Representative raw and idealized traces from smTIRF experiments where Cy3-labelled CRX HD binds to a surface tethered Ret4-NRE DNA molecule. B, C, D, The dwell-time distributions were constructed from all “ON” dwell times for Ret3-NRE DNA binding of 1 nM of CRX HD alone (B), or in the presence of 2.5 nM (C) and 5 nM of NRL DBD (D). The dissociation rate constants (koff) from a single-exponential fit of the distributions were (s−1): B, 0.303± 0.011; C, 0.218 ± 0.024 D. 0.154 ± 0.013.