Nicotinamide adenine dinucleotide(NAD^(+))/reduced NAD^(+)(NADH)and nicotinamide adenine dinucleotide phosphate(NADP^(+))/reduced NADP^(+)(NADPH)are essential metabolites involved in multiple metabolic pathways and ce...Nicotinamide adenine dinucleotide(NAD^(+))/reduced NAD^(+)(NADH)and nicotinamide adenine dinucleotide phosphate(NADP^(+))/reduced NADP^(+)(NADPH)are essential metabolites involved in multiple metabolic pathways and cellular processes.NAD^(+)and NADH redox couple plays a vital role in catabolic redox reactions,while NADPH is crucial for cellular anabolism and antioxidant responses.Maintaining NAD(H)and NADP(H)homeostasis is crucial for normal physiological activity and is tightly regulated through various mechanisms,such as biosynthesis,consumption,recycling,and conversion between NAD(H)and NADP(H).The conversions between NAD(H)and NADP(H)are controlled by NAD kinases(NADKs)and NADP(H)phosphatases[specifically,metazoan SpoT homolog-1(MESH1)and nocturnin(NOCT)].NADKs facilitate the synthesis of NADP^(+)from NAD^(+),while MESH1 and NOCT convert NADP(H)into NAD(H).In this review,we summarize the physiological roles of NAD(H)and NADP(H)and discuss the regulatory mechanisms governing NAD(H)and NADP(H)homeostasis in three key aspects:the transcriptional and posttranslational regulation of NADKs,the role of MESH1 and NOCT in maintaining NAD(H)and NADP(H)homeostasis,and the influence of the circadian clock on NAD(H)and NADP(H)homeostasis.In conclusion,NADKs,MESH1,and NOCT are integral to various cellular processes,regulating NAD(H)and NADP(H)homeostasis.Dysregulation of these enzymes results in various human diseases,such as cancers and metabolic disorders.Hence,strategies aiming to restore NAD(H)and NADP(H)homeostasis hold promise as novel therapeutic approaches for these diseases.展开更多
NADP(H) dependent retinol dehydrogenase/reductase (NRDR) was an important retinoic acid synthase, which was first purified from rabbit liver in 1997. In order to study the function of the NRDR gene,the full length cDN...NADP(H) dependent retinol dehydrogenase/reductase (NRDR) was an important retinoic acid synthase, which was first purified from rabbit liver in 1997. In order to study the function of the NRDR gene,the full length cDNA of bovine NRDR was cloned. According to the conserved sequences of human, mouse and rabbit NRDR cDNA, a pair of primers was designed to amplify a 294 bp DNA fragment of bovine liver NRDR, and then the full length of NRDR cDNA (AF487454) was cloned by using 3′ RACE and 5′ RACE. All the cloned NRDR proteins consist of 260 amino acid residues and showed high identity among them. The tri peptide of human, mouse and rabbit NRDR C end was SRL and that of bovine NRDR C end was SHL, but both were considered to be peroxisomal target signal 1 (PTS1). RT PCR demonstrated that NRDR gene was expressed in liver, heart, lung, kidney, stomach and intestine, and was not found in pancreas, muscle, artery and skin. The full length bovine NRDR cDNA has been successfully cloned and the sequence was analyzed. It provided a reliable foundation to investigate the biological function of this protein.展开更多
文摘Nicotinamide adenine dinucleotide(NAD^(+))/reduced NAD^(+)(NADH)and nicotinamide adenine dinucleotide phosphate(NADP^(+))/reduced NADP^(+)(NADPH)are essential metabolites involved in multiple metabolic pathways and cellular processes.NAD^(+)and NADH redox couple plays a vital role in catabolic redox reactions,while NADPH is crucial for cellular anabolism and antioxidant responses.Maintaining NAD(H)and NADP(H)homeostasis is crucial for normal physiological activity and is tightly regulated through various mechanisms,such as biosynthesis,consumption,recycling,and conversion between NAD(H)and NADP(H).The conversions between NAD(H)and NADP(H)are controlled by NAD kinases(NADKs)and NADP(H)phosphatases[specifically,metazoan SpoT homolog-1(MESH1)and nocturnin(NOCT)].NADKs facilitate the synthesis of NADP^(+)from NAD^(+),while MESH1 and NOCT convert NADP(H)into NAD(H).In this review,we summarize the physiological roles of NAD(H)and NADP(H)and discuss the regulatory mechanisms governing NAD(H)and NADP(H)homeostasis in three key aspects:the transcriptional and posttranslational regulation of NADKs,the role of MESH1 and NOCT in maintaining NAD(H)and NADP(H)homeostasis,and the influence of the circadian clock on NAD(H)and NADP(H)homeostasis.In conclusion,NADKs,MESH1,and NOCT are integral to various cellular processes,regulating NAD(H)and NADP(H)homeostasis.Dysregulation of these enzymes results in various human diseases,such as cancers and metabolic disorders.Hence,strategies aiming to restore NAD(H)and NADP(H)homeostasis hold promise as novel therapeutic approaches for these diseases.
文摘NADP(H) dependent retinol dehydrogenase/reductase (NRDR) was an important retinoic acid synthase, which was first purified from rabbit liver in 1997. In order to study the function of the NRDR gene,the full length cDNA of bovine NRDR was cloned. According to the conserved sequences of human, mouse and rabbit NRDR cDNA, a pair of primers was designed to amplify a 294 bp DNA fragment of bovine liver NRDR, and then the full length of NRDR cDNA (AF487454) was cloned by using 3′ RACE and 5′ RACE. All the cloned NRDR proteins consist of 260 amino acid residues and showed high identity among them. The tri peptide of human, mouse and rabbit NRDR C end was SRL and that of bovine NRDR C end was SHL, but both were considered to be peroxisomal target signal 1 (PTS1). RT PCR demonstrated that NRDR gene was expressed in liver, heart, lung, kidney, stomach and intestine, and was not found in pancreas, muscle, artery and skin. The full length bovine NRDR cDNA has been successfully cloned and the sequence was analyzed. It provided a reliable foundation to investigate the biological function of this protein.