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Cells 2021 Mar 6;10(3). Epub 2021 Mar 6.

Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.

It has been challenging to simultaneously improve photosynthesis and stress tolerance in plants. Crassulacean acid metabolism (CAM) is a CO-concentrating mechanism that facilitates plant adaptation to water-limited environments. We hypothesized that the ectopic expression of a CAM-specific phosphopyruvate carboxylase (PEPC), an enzyme that catalyzes primary CO fixation in CAM plants, would enhance both photosynthesis and abiotic stress tolerance. Read More

Plant Signal Behav 2021 Apr 10;16(4):1885894. Epub 2021 Feb 10.

National Engineering Laboratory of Wheat, Key Laboratory of Wheat Biology and Genetic Breeding in Central Huanghuai Area, Ministry of Agriculture, Institute of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, China.

This study assessed the responses of wild-type (WT) and transgenic expressing seven combinations of maize () genes phosphoenolpyruvate carboxylase (), pyruvate phosphate dikinase (), and NADP-malic enzyme () to high light. Our results showed that the net CO assimilation rate () and shoot dry weight of four of the transgenic genotypes were significantly different from those of WT under high-light treatment, being in the order of (PC-K-M) > (PC-K) > (PC), (PC-M) > WT. The other genotypes did not differ from WT. Read More

J Mol Cell Biol 2020 Dec 23. Epub 2020 Dec 23.

Division of Life Sciences, Korea University, Seoul, South Korea.

Hepatic gluconeogenesis is the central pathway for glucose generation in the body. The imbalance between glucose synthesis and uptake leads to metabolic diseases such as obesity, diabetes, and cardiovascular diseases. Small leucine zipper protein (sLZIP) is an isoform of LZIP and it mainly functions as a transcription factor. Read More

Front Plant Sci 2020 15;11:564463. Epub 2020 Oct 15.

C4 Rice Centre, International Rice Research Institute (IRRI), Los Baños, Philippines.

Introduction of a C photosynthetic pathway into C rice () requires installation of a biochemical pump that concentrates CO at the site of carboxylation in modified bundle sheath cells. To investigate the feasibility of this, we generated a quadruple line that simultaneously accumulates four of the core C photosynthetic enzymes from the NADP-malic enzyme subtype, phosphopyruvate carboxylase (PEPC), NADP-malate dehydrogenase (NADP-MDH), NADP-malic enzyme (NADP-ME), and pyruvate phosphate dikinase (PPDK). This led to enhanced enzyme activity and mild phenotypic perturbations but was largely neutral in its effects on photosynthetic rate. Read More

Plant Biotechnol J 2021 Mar 27;19(3):575-588. Epub 2020 Oct 27.

Australian Research Council Centre of Excellence for Translational Photosynthesis, Division of Plant Science, Research School of Biology, The Australian National University, Acton, ACT, Australia.

Introduction of a C photosynthetic mechanism into C crops offers an opportunity to improve photosynthetic efficiency, biomass and yield in addition to potentially improving nitrogen and water use efficiency. To create a two-cell metabolic prototype for an NADP-malic enzyme type C rice, we transformed Oryza sativa spp. japonica cultivar Kitaake with a single construct containing the coding regions of carbonic anhydrase, phosphoenolpyruvate (PEP) carboxylase, NADP-malate dehydrogenase, pyruvate orthophosphate dikinase and NADP-malic enzyme from Zea mays, driven by cell-preferential promoters. Read More

Am J Physiol Regul Integr Comp Physiol 2020 Jun 17. Epub 2020 Jun 17.

Department of Pharmacology, New York Medical College, United States.

20-Hydroxyeicosatetraenoic acid (20-HETE) has been linked to blood pressure (BP) regulation via actions on the renal microvasculature and tubules. We assessed tubular 20-HETE contribution to hypertension by generating transgenic mice overexpressing the CYP4A12-20-HETE synthase (PT-4a12 mice) under the control of the proximal tubule (PT)-specific promoter, phosphoenolpyruvate carboxykinase (PEPCK). 20-HETE levels in the kidney cortex of male (967±210 vs. Read More

J Biotechnol 2020 Jul 17;318:57-67. Epub 2020 May 17.

National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110067, India. Electronic address:

The study reports the identification and expression profiling of five major classes of C pathway-specific genes, namely, carbonic anhydrase (CaH), phosphoenolpyruvate carboxylase (PEPC), pyruvate orthophosphate dikinase (PPDK), NADP-dependent malate dehydrogenase (MDH) and NADP-dependent malic enzyme (NADP-ME), in the model species, Setaria italica and Setaria viridis. A total of 42 and 41 genes were identified in S. italica and S. Read More

J Dev Orig Health Dis 2020 06 23;11(3):285-296. Epub 2019 Sep 23.

Department of Animal Sciences, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.

Maternal high-fat diet (HFD) alters hypothalamic programming and disrupts offspring energy homeostasis in rodents. We previously reported that the loss of ERα signaling partially blocks the effects of maternal HFD in female offspring fed a standard chow diet. In a companion study, we determined if the effects of maternal HFD were magnified by an adult obesogenic diet in our transgenic mouse models. Read More

Photosynth Res 2019 Nov 19;142(2):153-167. Epub 2019 Jul 19.

School of Biological Sciences, Molecular Plant Sciences, Washington State University, Pullman, WA, 99164-4236, USA.

The engineering process of C photosynthesis into C plants requires an increased activity of phosphoenolpyruvate carboxylase (PEPC) in the cytosol of leaf mesophyll cells. The literature varies on the physiological effect of transgenic maize (Zea mays) PEPC (ZmPEPC) leaf expression in Oryza sativa (rice). Therefore, to address this issue, leaf-atmosphere CO and CO exchanges were measured, both in the light (at atmospheric O partial pressure of 1. Read More

Cell Rep 2019 07;28(3):759-772.e10

Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06519, USA; Departments of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06519, USA. Electronic address:

Mechanisms coordinating pancreatic β cell metabolism with insulin secretion are essential for glucose homeostasis. One key mechanism of β cell nutrient sensing uses the mitochondrial GTP (mtGTP) cycle. In this cycle, mtGTP synthesized by succinyl-CoA synthetase (SCS) is hydrolyzed via mitochondrial PEPCK (PEPCK-M) to make phosphoenolpyruvate, a high-energy metabolite that integrates TCA cycling and anaplerosis with glucose-stimulated insulin secretion (GSIS). Read More

J Biol Chem 2019 08 3;294(34):12743-12753. Epub 2019 Jul 3.

Departments of Medicine and Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York 10461

The sterol regulatory element-binding proteins (SREBPs) are a family of transcription factors best known for stimulating the expression of genes encoding key lipogenic enzymes. However, SREBP functions beyond lipid metabolism are less understood. Here, we show that hepcidin antimicrobial peptide (), encoding the hormone hepcidin essential for iron homeostasis and regulated by dietary iron and inflammation, is a target gene of the two SREBP isoforms SREBP-1a/c. Read More

Front Physiol 2019 22;10:262. Epub 2019 Mar 22.

Exercise Biology Group, Department of Sport and Health Sciences, Technical University of Munich, Munich, Germany.

Endurance is not only a key factor in many sports but endurance-related variables are also associated with good health and low mortality. Twin and family studies suggest that several endurance-associated traits are ≈50% inherited. However, we still poorly understand what DNA sequence variants contribute to endurance heritability. Read More

PLoS One 2019 11;14(3):e0213504. Epub 2019 Mar 11.

Rice Research Institute, Shenyang Agricultural University, Shenyang, China.

The DEP1 (dense and erect panicle 1) gene, which corresponds to the erect panicle architecture, shows a pleiotropic effect in increasing grain yield and nitrogen use efficiency (NUE) in rice. Nevertheless, it remains unclear whether the carbon-nitrogen metabolic balance changes as the dep1 allele enhances nitrogen uptake and assimilation. In this study, we generated transgenic Akitakomati plants by overexpressing dep1 and analyzed the carbon-nitrogen metabolic status, gene expression profiles, and grain yield and quality. Read More

Plant Sci 2019 Mar 29;280:197-205. Epub 2018 Nov 29.

Department of Plant Sciences, University of California, Davis, 95616, CA, USA. Electronic address:

Cecropin-B (CecB) is a peptide with well-established antimicrobial properties against different phytopathogenic bacteria. Despite modest action against Ralstonia solanacearum, its animal source limits the acceptance in transgenic applications. To overcome this, we selected eight alpha-helical (AH) cationic peptides derived from plant protein sequences and investigated their antimicrobial properties against R. Read More

J Pharmacol Exp Ther 2019 03 18;368(3):423-434. Epub 2018 Dec 18.

Lipoprotein Metabolism Laboratory, Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland (B.L.V., E.B.N., L.A.F., S.M.G., M.L.S., M.P., E.H., A.T.R.) and MedImmune, Gaithersburg, Maryland (M.J.A., S.K.K.).

Familial LCAT deficiency (FLD) is due to mutations in lecithin:cholesterol acyltransferase (LCAT), a plasma enzyme that esterifies cholesterol on lipoproteins. FLD is associated with markedly reduced levels of plasma high-density lipoprotein and cholesteryl ester and the formation of a nephrotoxic lipoprotein called LpX. We used a mouse model in which the LCAT gene is deleted and a truncated version of the SREBP1a gene is expressed in the liver under the control of a protein-rich/carbohydrate-low (PRCL) diet-regulated PEPCK promoter. Read More

Front Plant Sci 2018 23;9:1710. Epub 2018 Nov 23.

State Key Laboratory for Agrobiotechnology, Key Laboratory of Crop Heterosis and Utilization (MOE), Beijing Key Laboratory of Crop Genetic Improvement, China Agricultural University, Beijing, China.

Wheat ( L.) yield and quality are adversely affected by heat, drought, or the combination of these two stresses in many regions of the world. A phosphoenolpyruvate carboxylase kinase-related kinase gene, , was identified from our previous heat stress-responsive transcriptome analysis of heat susceptible and tolerant wheat cultivars. Read More

Biomed Pharmacother 2019 Feb 5;110:449-455. Epub 2018 Dec 5.

BIT&GS Technologies Co. Ltd., PR China. Electronic address:

The extract of Belamcanda chinensis (L.) leaves (BCLE) is a traditional Chinese herbal medicine for the treatment of hyperglycemia in Hainan province, South China. In this study, the effects of BCLE on obese diabetes were investigated using the KK-A mice. Read More

J Biol Chem 2019 01 20;294(3):1059-1069. Epub 2018 Nov 20.

the Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Illinois, Chicago, Illinois 60612,

FoxO proteins are major targets of insulin action, and FoxO1 mediates the effects of insulin on hepatic glucose metabolism. We reported previously that serpinB1 is a liver-secreted factor (hepatokine) that promotes adaptive β-cell proliferation in response to insulin resistance in the liver-specific insulin receptor knockout (LIRKO) mouse. Here we report that FoxO1 plays a critical role in promoting serpinB1 expression in hepatic insulin resistance in a non-cell-autonomous manner. Read More

Plant Physiol Biochem 2018 Sep 10;130:577-588. Epub 2018 Aug 10.

Institute of Food Crops, Jiangsu Rice Engineering Research Center, National Center for Rice Improvement (Nanjing), Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; College of Biology and Environment, Nanjing Forestry University, Nanjing, 210037, China.

The objective of this study was to reveal the physiological and molecular mechanisms of low-nitrogen (N) tolerance in transgenic plant lines containing C phosphoenolpyruvate carboxylase (C-PEPC) gene. The transgenic rice lines only over-expressing the maize C-PEPC) (PC) and their untransformed wild type, Kitaake (WT), were used in this study. At different N levels, the dry weight, total N content, carbon and N levels, photorespiration-related enzymatic activities, gene expression levels and photorespiration-related product accumulations were measured, as were the transgenic lines' agronomic traits. Read More

PLoS Genet 2018 07 11;14(7):e1007487. Epub 2018 Jul 11.

Ecole Polytechnique Fédérale de Lausanne (EPFL), School of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), Lausanne, Switzerland.

Altered glucose and lipid metabolism fuel cystic growth in polycystic kidneys, but the cause of these perturbations is unclear. Renal cysts also associate with mutations in Bicaudal C1 (Bicc1) or in its self-polymerizing sterile alpha motif (SAM). Here, we found that Bicc1 maintains normoglycemia and the expression of the gluconeogenic enzymes FBP1 and PEPCK in kidneys. Read More

Plant Physiol 2018 08 11;177(4):1396-1409. Epub 2018 Jun 11.

Academy of Scientific and Innovative Research, Council of Scientific and Industrial Research-Institute of Himalayan Bioresource Technology, P.O. Box 6, Palampur (H.P.) 176061, India.

We investigated the effect of the heterologous expression of (), (), and () on carbon (C) and nitrogen (N) metabolism in Arabidopsis (). These transgenes were expressed either separately or in different combinations. The highest gains in shoot dry weight were observed in transgenic lines coexpressing all three genes. Read More

Diabetes 2018 09 17;67(9):1748-1760. Epub 2018 May 17.

Department of Pharmacology, School of Basic Medical Sciences, 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics, Key Laboratory of Immune Microenvironment and Disease (Ministry of Education), Tianjin Medical University, Tianjin, People's Republic of China

Gluconeogenesis is drastically increased in patients with type 2 diabetes and accounts for increased fasting plasma glucose concentrations. Circulating levels of prostaglandin (PG) F are also markedly elevated in diabetes; however, whether and how PGF regulates hepatic glucose metabolism remain unknown. Here, we demonstrated that PGF receptor (F-prostanoid receptor [FP]) was upregulated in the livers of mice upon fasting- and diabetic stress. Read More

Transgenic Res 2018 06 4;27(3):301-313. Epub 2018 May 4.

Faculty of Agriculture Sciences, Shahed University, Tehran, Iran.

In this study, the compositions of transgenic potatoes (TPs) resistant to potato tuber moth (Phthorimaea operculella) were compared with those of its non-transgenic (NTP) counterparts. The light inducible promoter, phosphoenolpyruvate carboxylase led to the expression of Cry1Ab only in the leaves and light-treated tubers of the TPs. No significant differences were found in the moisture, ash, dry weight, total soluble protein, carbohydrate, starch, fiber, ascorbate, cations, anions, fatty acids, and glycoalkaloids contents of TP and NTP. Read More

Biotechnol Biofuels 2018 24;11:122. Epub 2018 Apr 24.

1Department of Plant Sciences, University of Tennessee, Knoxville, TN USA.

Background: Genetic engineering of switchgrass ( L.) for reduced cell wall recalcitrance and improved biofuel production has been a long pursued goal. Up to now, constitutive promoters have been used to direct the expression of cell wall biosynthesis genes toward attaining that goal. Read More

J Endocrinol 2018 07 19;238(1):1-12. Epub 2018 Apr 19.

Department of Veterinary and Animal SciencesFaculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark

To evaluate the long-term impacts of early-life nutritional manipulations on glucagon secretion and hepatic signalling, thirty-six twin-pregnant ewes during their last trimester were exposed to NORM (fulfilling 100% of daily energy/protein requirements), HIGH (fulfilling 150/110% of daily energy/protein requirements) or LOW (50% of NORM) diets. Twin lambs were assigned after birth to a moderate (CONV) or high-carbohydrate high-fat (HCHF) diet until 6 months. Then, responses in plasma glucagon concentrations and glucagon ratios relative to previously reported values for insulin, glucose and lactate were determined after intravenous bolus injections of glucose or propionate (fed and 2-day fasting state). Read More

Plant Sci 2018 Jun 15;271:52-61. Epub 2018 Mar 15.

Laboratory of Cotton Genetics, Genomics and Breeding/Beijing Key Laboratory of Crop Genetic Improvement/Key Laboratory of Crop Heterosis and Utilization of Ministry of Education, College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193, China. Electronic address:

Phosphoenolpyruvate carboxylase (PEPCase) mainly produces oxaloacetic acid for tricarboxylic acid (TCA) cycle. Here we reported that GhPEPC2 silencing with PEPC2-RNAi vector could regulate oil and protein accumulation in cottonseeds. In GhPEPC2 transgenic plants, PEPCase activities in immature embryos were significantly reduced, and the oil content in seed kernel was increased 7. Read More

Plant Physiol 2017 Dec 31;175(4):1624-1633. Epub 2017 Oct 31.

Boyce Thompson Institute, Cornell University, Ithaca, New York 14853

In maize (), Bundle Sheath Defective2 (BSD2) plays an essential role in Rubisco biogenesis and is required for correct bundle sheath (BS) cell differentiation. Yet, BSD2 RNA and protein levels are similar in mesophyll (M) and BS chloroplasts, although Rubisco accumulates only in BS chloroplasts. This raises the possibility of additional BSD2 roles in cell development. Read More

J Plant Physiol 2017 Nov 31;218:206-221. Epub 2017 Aug 31.

Institute of Food Crops, Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R and D Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing 210014, PR China.

To understand the link between long-term drought tolerance and short-term drought responses in plants, transgenic rice (Oryza sativa L.) plants over-expressing the maize Cpepc gene encoding phosphoenolpyruvate carboxylase (PC) and wild-type (WT) rice plants were subjected to PEG 6000 treatments to simulate drought stress. Compared with WT, PC had the higher survival rate and net photosynthetic rate after 16days of drought treatment, and had higher relative water content in leaves after 2h of drought treatment as well, conferring drought tolerance. Read More

Plant Cell 2017 Oct 8;29(10):2519-2536. Epub 2017 Sep 8.

Department of Functional and Comparative Genomics, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom

Phosphopyruvate carboxylase (PPC; EC 4.1.1. Read More

Front Plant Sci 2017 30;8:434. Epub 2017 Mar 30.

Department of Agronomy and Horticulture, University of Nebraska-LincolnLincoln, NE, USA.

Nitrogen is essential for plant growth and development. Improving the ability of plants to acquire and assimilate nitrogen more efficiently is a key agronomic parameter that will augment sustainability in agriculture. A transcription factor approach was pursued to address improvement of nitrogen use efficiency in two major commodity crops. Read More