Fig. 2.

The FQNLF motif binds to the canonical binding site in Hsp70 in the absence of nucleotides. a Binding of NTD_1-155to the canonical cleft of Hsp70_SBD at 2 μM in the absence of nucleotides was measured by competition with the canonical peptide LVEAVY labelled with a FAM fluorophore (25 nM) as measured by FP. NR, a bona fide substrate of Hsp70_SBD, was used as positive control. Data are the average of at least three independent experiments performed in duplicate on different days and the error bars represent S.E.M. b Direct binding of NTD_1-155 to Hsp70_SBD in the absence of nucleotides was measured by ITC: the top panel represents the raw data whereas the lower panel represents the integrated heat peaks and the fit to the one-site binding model. Source data for a are available as Source Data file