InterPro domain: IPR040109

Nocturnin is a poly(A)-specific 3' exonuclease that specifically degrades the 3' poly(A) tail of RNA in a process known as deadenylation. Nocturnin is expressed in the cytoplasm of Xenopus laevis retinal photoreceptor cells in a rhythmic fashion, and it has been proposed that it participates in posttranscriptional regulation of the circadian clock or its outputs, and that the mRNA target(s) of this deadenylase are circadian clock-related [ 1 ]. In mouse, the nocturnin gene, mNoc, is expressed in a circadian pattern in a range of tissues including retina, spleen, heart, kidney, and liver. It is highly expressed in bone-marrow stromal cells, adipocytes and hepatocytes [ 2 ]. In mammals, nocturnin plays a role in regulating mesenchymal stem-cell lineage allocation, perhaps through regulating PPAR-gamma (peroxisome proliferator-activated receptor-gamma) nuclear translocation [ 3 ]. Nocturnin expression depends on the circadian clock and nutrient status. Loss of this activity results in increased metabolic flux and reduced obesity [ 4 ].

1. Nocturnin, a deadenylase in Xenopus laevis retina: a mechanism for posttranscriptional control of circadian-related mRNA. Curr. Biol. 13, 189-98
2. Rhythmic expression of Nocturnin mRNA in multiple tissues of the mouse. BMC Dev. Biol. 1, 9
3. A circadian-regulated gene, Nocturnin, promotes adipogenesis by stimulating PPAR-gamma nuclear translocation. Proc. Natl. Acad. Sci. U.S.A. 107, 10508-13
4. Temporal Control of Metabolic Amplitude by Nocturnin. Cell Rep 22, 1225-1235