Figure 2.

The TZF domain of MEX-5 is partially unstructured in the RNA-free state. Above the panels, a schematic representation of the TZF domain depicts the ZFs as rectangles and the linker region as a line. The circles indicate residues along the primary sequence with an assigned crosspeak in the ¹⁵N-¹H HSQC spectrum. (A) The ¹⁵N-¹H HSQC spectrum of MEX-5 TZF domain is missing all crosspeaks from ZF1 and part of the linker. (B) Zn²⁺ titration of the TZF domain of MEX-5, monitored by NMR spectroscopy, is shown. Average crosspeak intensities from the ¹⁵N-¹H HSQC spectra are shown as a function of zinc equivalents added to the protein, errors are estimated from the standard deviation. A linear regression is applied to the first part of the curve, and the resulting slope is shown in the plot.