Snail NSCaTELCav1 and mammalian NSCaTECav1.2 peptides assume an alpha-helix upon binding calmodulin (CaM).
(A) 17 mer NSCaTE and 21 mer IQ peptide sequences are used in circular dichroism (Figures 6) and Gel Shift Mobility Assays (Figures 7). (B,C) Differential spectra of NSCaTE peptide indicate a helical transformation with snail and mammalian NSCaTE upon addition of the helix stabilizing agent, trifluoroethanol (TFE: dashed line; no TFE: solid line, Figure 6B) or upon addition to CaM (solid line = 1∶1 CaM:peptide, dashed line = 1∶2 CaM:peptide, Figure 6C). Each trace is obtained by subtracting the 10 µM CaM-alone trace from the corresponding NSCaTE+CaM spectrum. Y axis units are mean residue ellipticity or (θ), (difference in spectra corrected for total protein/peptide concentration).