Phosphatase which catalyzes the conversion of NADP(+) to NAD(+) and of NADPH to NADH (By similarity). Shows a small preference for NADPH over NADP(+) (By similarity). Represses translation and promotes degradation of target mRNA molecules (By similarity). Plays an important role in post-transcriptional regulation of metabolic genes under circadian control (PubMed:20685873, PubMed:20498072). Exerts a rhythmic post-transcriptional control of genes necessary for metabolic functions including nutrient absorption, glucose/insulin sensitivity, lipid metabolism, adipogenesis, inflammation and osteogenesis (PubMed:20498072, PubMed:22082366, PubMed:21820310, PubMed:22073225, PubMed:22331129). Plays an important role in favoring adipogenesis over osteoblastogenesis and acts as a key regulator of the adipogenesis/osteogenesis balance (PubMed:20498072, PubMed:22082366). Promotes adipogenesis by facilitating PPARG nuclear translocation which activates its transcriptional activity (PubMed:20498072). Regulates circadian expression of NOS2 in the liver and negatively regulates the circadian expression of IGF1 in the bone (PubMed:22073225, PubMed:20685873). Critical for proper development of early embryos (PubMed:23449310). H2O + NADP(+) = NAD(+) + phosphate H2O + NADPH = NADH + phosphate Binds 2 magnesium ions, but the ions are only loosely bound to the protein. Interacts with PPARG. Highly expressed in the differentiated adipocyte (at protein level). Ubiquitous. Expression is highest in oocytes, begins to decrease after fertilization by the 4-cell stage and then slightly increases up to the blastocyst stage. Immediate early gene (IEG) showing acute responses to several stimuli including serum shock, phorbol ester, lipopolysaccharide (LPS) and rosiglitazone, a PPARG agonist. Exhibits a high amplitude circadian rhythm with maximal levels in early evening. In constant darkness or constant light, the amplitude of the rhythm decreases. Expression is regulated by both light and food-entrained cues and by the CLOCK-ARNTL/BMAL1 heterodimer and PPARG. Up-regulated in cells undergoing adipogenesis. Mice exhibit metabolic defects including a resistance to diet-induced obesity, decreased fat storage, changes in lipid-related gene expression profiles in the liver, and altered glucose and insulin sensitivities. Exhibit a delayed early embryo development and at 12 weeks of age show enhanced skeletal mass and increased osteoblastogenesis. Belongs to the CCR4/nocturin family. Was initially shown to have low deadenylase activity that was lost when the metal-binding Glu was mutated (PubMed:17400819). Later studies showed that the purified protein lacked deadenylase activity (PubMed:29860338). Was subsequently shown to act as a phosphatase (By similarity).