May be a redox sensor protein. Negative transcriptional regulator involved in the post-transcriptional modulation of the GATA-type transcription factor nit-2, forming part of a system controlling nitrogen metabolite repression (By similarity). Interacts with nit-2. Belongs to the NmrA-type oxidoreductase family. Lacks the conserved Tyr residue in position 211 in the active site triad of Ser-Tyr-Lys necessary for dehydrogenase activity, suggesting that it has no oxidoreductase activity.