eTAFH domain binds peptides with a conserved (D/E)LXXLL motif from HEB, cMyb, N-CoR, and STAT6. (A) Overlays of selected amides in the 15N-1H HSQC spectra of the eTAFH domain recorded as a function of the concentration of each peptide. Each column represents titration data for 3 separate amides with one particular peptide. (B) Kd determination using chemical shift changes resulting from titrations of each peptide. The 3 best fits from changes in 1HN shifts for each peptide are displayed. (C) Results of a Kd determination using fluorescence polarization with 0.2 μM fluorescein-labeled HEB peptide (FLSN-TDKELSDLLD) and increasing concentrations of eTAFH. Results of one titration are shown. Two independent experiments were carried out resulting in Kd = 12.5 ± 2.1 μM. (D) Sequence alignment of peptides examined for eTAFH binding. Consensus amino acids are colored in blue. Asterisks indicate residues in HEB whose side chains contact the eTAFH domain.