Figure 3.

CNBH domains of CNNM proteins do not bind cyclic nucleotides. A, thermal shift assays of the denaturation of the CNBH domains of CNNM1–4 in the presence and absence of 1 mm cyclic nucleotides and 1 mm Mg²⁺. Each experiment was performed in triplicates. Error bars, S.E. B, two-dimensional ¹H-¹⁵N correlation spectra of CNNM4 CNBH domain without nucleotide or 3 mm cAMP. No significant shifts were observed, indicating no ligand binding.