As one of the key enzymes in cell metabolism, the activity of citrate synthase 3 (CS3) regulates the substance and energy metabolism of organisms. The protein members of CS3 family were identified from the whole genome of apple, and bioinformatics analysis was performed and expression patterns were analyzed to provide a theoretical basis for studying the potential function of CS3 gene in apple. BLASTp was used to identify members of the apple CS3 family based on the GDR database, and the basic information of CS3 protein sequence, subcellular localization, domain composition, phylogenetic relationship and chromosome localization were analyzed by Pfam, SMART, MEGA5.0, clustalx.exe, ExPASy Proteomics Server, MEGAX, SOPMA, MEME, WoLF PSORT and other software. The tissue expression and inducible expression characteristics of 6 CS3 genes in apple were determined by acid content and real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). Apple CS3 gene family contains 6 members, and these CS3 proteins contain 473-608 amino acid residues, with isoelectric point distribution between 7.21 and 8.82. Subcellular localization results showed that CS3 protein was located in mitochondria and chloroplasts, respectively. Phylogenetic analysis divided them into 3 categories, and the number of genes in each subfamily was 2. Chromosome localization analysis showed that CS3 gene was distributed on different chromosomes of apple. The secondary structure of protein is mainly α-helix, followed by random curling, and the proportion of β-angle is the smallest. The 6 members were all expressed in different apple tissues. The overall expression trend from high to low was the highest relative expression content of MdCS3.4, followed by MdCS3.6, and the relative expression level of other members was in the order of MdCS3.3 > MdCS3.2 > MdCS3.1 > MdCS3.5. qRT-PCR results showed that MdCS3.1 and MdCS3.3 genes had the highest relative expression in the pulp of 'Chengji No. 1' with low acid content, and MdCS3.2 and MdCS3.3 genes in the pulp of 'Asda' with higher acid content had the highest relative expression. Therefore, in this study, the relative expression of CS3 gene in apple cultivars with different acid content in different apple varieties was detected, and its role in apple fruit acid synthesis was analyzed. The experimental results showed that the relative expression of CS3 gene in different apple varieties was different, which provided a reference for the subsequent study of the quality formation mechanism of apple.
Citric Acid ; Malus/genetics* ; Citrate (si)-Synthase ; Phylogeny ; Citrates

Pathogens like bacteria and protozoa, which affect human and animal health worldwide, can be transmitted by vectors like ticks. To investigate the epidemiology and genetic diversity of bacteria and protozoans carried by ticks in Chengmai county of Hainan province, China, 285 adult hard ticks belonging to two species [
Anaplasmataceae/isolation & purification* ; Animals ; Chaperonin 60/genetics* ; China ; Citrate (si)-Synthase/genetics* ; Coccidia/isolation & purification* ; Coxiellaceae/isolation & purification* ; Insect Vectors/microbiology* ; Islands ; Ixodidae/microbiology* ; Phylogeny ; Piroplasmia/isolation & purification* ; RNA, Ribosomal, 16S/genetics* ; RNA, Ribosomal, 18S/genetics*

BACKGROUND/OBJECTIVES: The study was conducted to evaluate the effects of dietary leucine supplementation on mitochondrial biogenesis and energy metabolism in the liver of normal birth weight (NBW) and intrauterine growth-retarded (IUGR) weanling piglets. MATERIALS/METHODS: A total of sixteen pairs of NBW and IUGR piglets from sixteen sows were selected according to their birth weight. At postnatal day 14, all piglets were weaned and fed either a control diet or a leucine-supplemented diet for 21 d. Thereafter, a 2 × 2 factorial experimental design was used. Each treatment consisted of eight replications with one piglet per replication. RESULTS: Compared with NBW piglets, IUGR piglets had a decreased (P < 0.05) hepatic adenosine triphosphate (ATP) content. Also, IUGR piglets exhibited reductions (P < 0.05) in the activities of hepatic mitochondrial pyruvate dehydrogenase (PDH), citrate synthase (CS), α-ketoglutarate dehydrogenase (α-KGDH), malate dehydrogenase (MDH), and complexes I and V, along with decreases (P < 0.05) in the concentration of mitochondrial DNA (mtDNA) and the protein expression of hepatic peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α). Dietary leucine supplementation increased (P < 0.05) the content of ATP, and the activities of CS, α-KGDH, MDH, and complex V in the liver of piglets. Furthermore, compared to those fed a control diet, piglets given a leucine-supplemented diet exhibited increases (P < 0.05) in the mtDNA content and in the mRNA expressions of sirtuin 1, PGC-1α, nuclear respiratory factor 1, mitochondrial transcription factor A, and ATP synthase, H+ transporting, mitochondrial F1 complex, β polypeptide in liver. CONCLUSIONS: Dietary leucine supplementation may exert beneficial effects on mitochondrial biogenesis and energy metabolism in NBW and IUGR weanling piglets.
Adenosine Triphosphate ; Birth Weight* ; Citrate (si)-Synthase ; Diet ; DNA, Mitochondrial ; Energy Metabolism* ; Fetal Growth Retardation ; Leucine* ; Liver ; Malate Dehydrogenase ; Nuclear Respiratory Factor 1 ; Organelle Biogenesis* ; Oxidoreductases ; Parturition* ; Peroxisomes ; Pyruvic Acid ; Research Design ; RNA, Messenger ; Sirtuin 1 ; Transcription Factors

Calreticulin (CALR), a multifunctional protein thoroughly researched in mammals, comprises N-, P-, and C-domain and has roles in calcium homeostasis, chaperoning, clearance of apoptotic cells, cell adhesion, and also angiogenesis. In this study, the spatial and temporal expression patterns of the Opisthorchis viverrini CALR gene were analyzed, and calcium-binding and chaperoning properties of recombinant O. viverrini CALR (OvCALR) investigated. OvCALR mRNA was detected from the newly excysted juvenile to the mature parasite by RT-PCR while specific antibodies showed a wide distribution of the protein. OvCALR was localized in tegumental cell bodies, testes, ovary, eggs, Mehlis’ gland, prostate gland, and vitelline cells of the mature parasite. Recombinant OvCALR showed an in vitro suppressive effect on the thermal aggregation of citrate synthase. The recombinant OvCALR C-domain showed a mobility shift in native gel electrophoresis in the presence of calcium. The results imply that OvCALR has comparable function to the mammalian homolog as a calcium-binding molecular chaperone. Inferred from the observed strong immunostaining of the reproductive tissues, OvCALR should be important for reproduction and might be an interesting target to disrupt parasite fecundity. Transacetylase activity of OvCALR as reported for calreticulin of Haemonchus contortus could not be observed.
Antibodies ; Calcium ; Calreticulin* ; Cell Adhesion ; Cell Body ; Citrate (si)-Synthase ; Eggs ; Electrophoresis ; Female ; Fertility ; Haemonchus ; Homeostasis ; In Vitro Techniques ; Mammals ; Molecular Chaperones ; Opisthorchis* ; Ovary ; Ovum ; Parasites ; Prostate ; Reproduction ; RNA, Messenger ; Testis ; Vitellins

To screen molecular chaperones similar to small heat shock proteins (sHsps), but without alpha-crystalline domain, heat-stable proteins from Schizosaccharomyces pombe were analyzed by 2-dimensional electrophoresis and matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Sixteen proteins were identified, and four recombinant proteins, including cofilin, NTF2, pyridoxin biosynthesis protein (Snz1) and Wos2 that has an alpha-crystalline domain, were purified. Among these proteins, only Snz1 showed the anti-aggregation activity against thermal denaturation of citrate synthase. However, pre-heating of NTF2 and Wos2 at 70degrees C for 30 min, efficiently prevented thermal aggregation of citrate synthase. These results indicate that Snz1 and NTF2 possess molecular chaperone activity similar to sHsps, even though there is no alpha-crystalline domain in their sequences.
alpha-Crystallins ; Citrate (si)-Synthase ; Electrophoresis ; Heat-Shock Proteins, Small* ; Mass Screening* ; Mass Spectrometry ; Molecular Chaperones* ; Pyridoxine ; Recombinant Proteins ; Schizosaccharomyces*

OBJECTIVETo determine the roles of mitochondrial apoptosis and energy metabolism in hepatocytes during the pathogenic process of acute renal failure (ALF) by assessing disease-related differential activities of several key mitochondrial enzymes, including citrate synthase (CS), carnitine palmitoyltransferase-1 (CPT-1) and cytochrome c oxidase (COX).

METHODSThirty-two male Sprague Dawley rats were given D-galactosamine followed by and lipopolysaccharide (LPS) to induce acute liver failure and sacrificed after 4 (4 h group), 8 (8 h group) 12 (12 h group) and 24 hours (24 h group) of treatment. Eight unmodeled rats served as controls. Effects related to apoptosis were evaluated by pathological analysis of hepatic tissues and TUNEL staining. Ultrastructural changes in mitochondria were assessed by electron microscopy. The activity and expression of CS, CPT-1 and COX were measured.

RESULTSHepatocyte apoptosis was present in the 4 h treatment group and was increased obviously in the 8 h treatment group. Hepatocyte necrosis was first observed in the 12 h treatment group and was significantly higher in the 24 h treatment group, with inflammatory cell invasion. Ultrastructural changes in mitochondria were present in the 4 h treatment group, and the 24 h treatment group showed mitochondria with completely destroyed outer membranes, which resulted in mitochondrial collapse. Activity and protein expression of CS, CPT-1 and COX were increased in the 4 h group (vs. controls), were at their peak in the 8 h group (CS:t =1.481, P less than 0.01; CPT-1:t =2.619, P less than 0.05; COX:t =1.014, P less than 0.01) and showed a decreasing trend in the 12 h group. In addition, the activities of CS, CPT-1 and COX were enhanced at the stage of hepatocyte apoptosis, suggesting that these enzymes were involved in the initiation and development of ALF.

CONCLUSIONEnergy metabolism plays an important role in hepatocyte apoptosis during ALF.

Animals ; Apoptosis ; Carnitine O-Palmitoyltransferase ; metabolism ; Citrate (si)-Synthase ; metabolism ; Disease Models, Animal ; Electron Transport Complex IV ; metabolism ; Hepatocytes ; cytology ; enzymology ; Liver Failure, Acute ; metabolism ; pathology ; Male ; Mitochondria ; ultrastructure ; Rats ; Rats, Sprague-Dawley

As a large family of hydrolases, GTPases are widespread in cells and play the very important biological function of hydrolyzing GTP into GDP and inorganic phosphate through binding with it. GTPases are involved in cell cycle regulation, protein synthesis, and protein transportation. Chaperones can facilitate the folding or refolding of nascent peptides and denatured proteins to their native states. However, chaperones do not occur in the native structures in which they can perform their normal biological functions. In the current study, the chaperone activity of the conserved GTPases of Escherichia coli is tested by the chemical denaturation and chaperone-assisted renaturation of citrate synthase and α-glucosidase. The effects of ribosomes and nucleotides on the chaperone activity are also examined. Our data indicate that these conserved GTPases have chaperone properties, and may be ancestral protein folding factors that have appeared before dedicated chaperones.
Citrate (si)-Synthase ; chemistry ; Cloning, Molecular ; Conserved Sequence ; Escherichia coli ; cytology ; enzymology ; GTP Phosphohydrolases ; chemistry ; genetics ; isolation & purification ; metabolism ; Guanosine Diphosphate ; pharmacology ; Guanosine Triphosphate ; analogs & derivatives ; pharmacology ; Molecular Chaperones ; chemistry ; genetics ; isolation & purification ; metabolism ; Protein Denaturation ; drug effects ; Protein Renaturation ; drug effects ; Ribosomes ; metabolism ; alpha-Glucosidases ; chemistry

Exercise training (ET) and selenium (SEL) were evaluated either individually or in combination (COMBI) for their effects on expression of glucose (AMPK, PGC-1alpha, GLUT-4) and lactate metabolic proteins (LDH, MCT-1, MCT-4, COX-IV) in heart and skeletal muscles in a rodent model (Goto-Kakisaki, GK) of diabetes. Forty GK rats either remained sedentary (SED), performed ET, received SEL, (5 micromol/kg body wt(-1)/day(-1)) or underwent both ET and SEL treatment for 6 wk. ET alone, SEL alone, or COMBI resulted in a significant lowering of lactate, glucose, and insulin levels as well as a reduction in HOMA-IR and AUC for glucose relative to SED. Additionally, ET alone, SEL alone, or COMBI increased glycogen content and citrate synthase (CS) activities in liver and muscles. However, their effects on glycogen content and CS activity were tissue-specific. In particular, ET alone, SEL alone, or COMBI induced upregulation of glucose (AMPK, PGC-1alpha, GLUT-4) and lactate (LDH, MCT-1, MCT-4, COX-IV) metabolic proteins relative to SED. However, their effects on glucose and lactate metabolic proteins also appeared to be tissue-specific. It seemed that glucose and lactate metabolic protein expression was not further enhanced with COMBI compared to that of ET alone or SEL alone. These data suggest that ET alone or SEL alone or COMBI represent a practical strategy for ameliorating aberrant expression of glucose and lactate metabolic proteins in diabetic GK rats.
Animals ; Area Under Curve ; Citrate (si)-Synthase ; Glucose ; Glycogen ; Heart ; Insulin ; Lactic Acid ; Liver ; Muscle, Skeletal ; Muscles ; Proteins ; Rats ; Rodentia ; Selenium ; Up-Regulation

This study was carried out to investigate an enhancing effect of black ginseng extract (BGE) on exercise capacity in an endurance exercising animal model. Fifty Sprague-Dawley rats were assigned to 5 experimental groups including non-training control, training control, and 3 treated groups (BGE at doses of 75, 150 and 300 mg/kg). The animals were treated with BGE for 6 weeks and their exercise ability in the maximal running distance test was determined using a treadmill every week. The blood lactic acid (LA) level and the activity of citrate synthase (CS) in the muscle were also measured after the exercise. The levels of glucose and glucose-6-phosphate (G-6-P) in the liver and muscle were determined using commercial assay kits. BGE treatments at the doses of 150 and 300 mg/kg significantly increased the exercise capacity compared with the non-training control or training control groups (P<0.05). The level of blood LA was decreased but the activity of CS was increased by the treatment of BGE at the dose of 300 mg/kg compared with the training control group. The level of G-6-P in the liver was elevated by the treatment of BGE at the dose of 300 mg/kg, compared to the training group. As compared with non-training control group, the treatments of BGE increased the levels of glucose and G-6-P in the liver and soleus muscle of rats. These results indicate that BGE have a potential for promoting exercise capacity by increasing CS activity in the muscle and decreasing LA in the serum of rats. These results also suggested that BGE can be used as a candidate supplement of health food products for promoting endurance exercise capacity in human athletes.
Animals ; Athletes ; Citrate (si)-Synthase ; Exercise ; Glucose ; Glucose-6-Phosphate ; Food, Organic ; Humans ; Lactic Acid ; Liver ; Models, Animal ; Muscle, Skeletal ; Muscles ; Panax ; Rats ; Rats, Sprague-Dawley ; Running

This study was carried out to investigate an enhancing effect of black ginseng extract (BGE) on exercise capacity in an endurance exercising animal model. Fifty Sprague-Dawley rats were assigned to 5 experimental groups including non-training control, training control, and 3 treated groups (BGE at doses of 75, 150 and 300 mg/kg). The animals were treated with BGE for 6 weeks and their exercise ability in the maximal running distance test was determined using a treadmill every week. The blood lactic acid (LA) level and the activity of citrate synthase (CS) in the muscle were also measured after the exercise. The levels of glucose and glucose-6-phosphate (G-6-P) in the liver and muscle were determined using commercial assay kits. BGE treatments at the doses of 150 and 300 mg/kg significantly increased the exercise capacity compared with the non-training control or training control groups (P<0.05). The level of blood LA was decreased but the activity of CS was increased by the treatment of BGE at the dose of 300 mg/kg compared with the training control group. The level of G-6-P in the liver was elevated by the treatment of BGE at the dose of 300 mg/kg, compared to the training group. As compared with non-training control group, the treatments of BGE increased the levels of glucose and G-6-P in the liver and soleus muscle of rats. These results indicate that BGE have a potential for promoting exercise capacity by increasing CS activity in the muscle and decreasing LA in the serum of rats. These results also suggested that BGE can be used as a candidate supplement of health food products for promoting endurance exercise capacity in human athletes.
Animals ; Athletes ; Citrate (si)-Synthase ; Exercise ; Glucose ; Glucose-6-Phosphate ; Food, Organic ; Humans ; Lactic Acid ; Liver ; Models, Animal ; Muscle, Skeletal ; Muscles ; Panax ; Rats ; Rats, Sprague-Dawley ; Running