(B) Amino‐acid sequence of NAF‐1. Peptide sequences identified by mass spectrometry are indicated by a double underline. The TM domain is indicated by a bold single underline. Cys residues in the cytosolic domain are denoted with asterisks (*). The CDGSH domain is highlighted in grey, and the predicted 2Fe‐2S coordinating Cys‐3‐His‐1 aa are marked in bold. A downwards arrow head (∨) represents the site in which a Flag epitope was inserted. A double‐lined arrow (⇓) indicates the Glu residue that when mutated (E37Q) causes WFS2. Predicted phosphorylation sites found using the PhosphoMotif Finder from the Human Protein Reference Database (HPRD) are indicated in bold within a box; β‐adrenergic receptor kinase substrate motif (aa 25-29), PKA and PKC kinase substrate motifs (aa 32-34 and 67-69), and casein kinase II substrate motif (aa 34-37). 