Proline Oxidase Research Articles

Physiological importance of polyamines.

Polyamines are polycationic molecules that contain two or more amino groups (-NH3 +) and are present in all eukaryotic and prokaryotic cells. Polyamines are synthesized from arginine, ornithine, and proline, and from methionine as the methyl-group donor. In the traditional pathway for polyamine synthesis, arginase converts arginine into ornithine, which is decarboxylated by ornithine decarboxylase (ODC1) to generate putrescine. The latter is converted to spermidine and spermine. Recent studies have indicated the existence of 'non-classical pathways' for the generation of putrescine from arginine and proline in animal cells. Specifically, arginine decarboxylase (ADC) catalyzes the conversion of arginine into agmatine, which is hydrolyzed by agmatinase (AGMAT) to form putrescine. Additionally, proline is oxidized by proline oxidase to yield pyrroline-5-carboxylate, which undergoes transamination with glutamate to produce ornithine for decarboxylation by ODC1. Intracellular production of polyamines is controlled by antizymes binding to and inactivating ODC1. Polyamines exert effects that include stimulation of cell division and proliferation, gene expression for the survival of cells, DNA and protein synthesis, regulation of apoptosis, oxidative stress, angiogenesis, and cell-cell communication activity. Accordingly, polyamines are essential for early embryonic development and successful pregnancy outcome in mammals. In this paper the main concepts on the history, structure and molecular pathways of polyamines as well as their physiological role on angiogenesis, and reproductive physiology are reviewed.

Associations between neurodevelopmental genes, neuroanatomy, and ultra high risk symptoms of psychosis in 22q11.2 deletion syndrome.

22q11.2 deletion syndrome is a neurogenetic disorder resulting in the deletion of over 40 genes. Up to 40% of individuals with 22q11.2DS develop schizophrenia, though little is known about the underlying mechanisms. We hypothesized that allelic variation in functional polymorphisms in seven genes unique to the deleted region would affect lobar brain volumes, which would predict risk for psychosis in youth with 22q11.2DS. Participants included 56 individuals (30 males) with 22q11.2DS. Anatomic MR images were collected and processed using Freesurfer. Participants were genotyped for 10 SNPs in the COMT, DGCR8, GNB1L, PIK4CA, PRODH, RTN4R, and ZDHHC8 genes. All subjects were assessed for ultra high risk symptoms of psychosis. Allelic variation of the rs701428 SNP of RTN4R was significantly associated with volumetric differences in gray matter of the lingual gyrus and cuneus of the occipital lobe. Moreover, occipital gray matter volumes were robustly associated with ultra high risk symptoms of psychosis in the presence of the G allele of rs701428. Our results suggest that RTN4R, a relatively under-studied gene at the 22q11 locus, constitutes a susceptibility gene for psychosis in individuals with this syndrome through its alteration of the architecture of the brain. © 2017 Wiley Periodicals, Inc.

Hyperprolinemia Type IA

Objective:Hyperprolinemia type I (HPI) is a rare and inherited autosomal recessive disorder caused by proline oxidase deficiency. Hyperprolinemia type 1 is biochemically defined as high plasma prol...

Proline accumulation protects Saccharomyces cerevisiae cells in stationary phase from ethanol stress by reducing reactive oxygen species levels.

During fermentation processes, Saccharomyces cerevisiae cells are exposed to multiple stresses, including a high concentration of ethanol that represents toxicity through intracellular reactive oxygen species (ROS) generation. We previously reported that proline protected yeast cells from damage caused by various stresses, such as freezing and ethanol. As an anti-oxidant, proline is suggested to scavenge intracellular ROS. In this study, we examined the role of intracellular proline during ethanol treatment in S. cerevisiae strains that accumulate different concentrations of proline. When cultured in YPD medium, there was a significant accumulation of proline in the put1 mutant strain, which is deficient in proline oxidase, in the stationary phase. Expression of the mutant PRO1 gene, which encodes the γ-glutamyl kinase variant (Asp154Asn or Ile150Thr) with desensitization to feedback inhibition by proline in the put1 mutant strain, showed a prominent increase in proline content as compared with that of the wild-type strain. The oxidation level was clearly increased in wild-type cells after exposure to ethanol, indicating that the generation of ROS occurred. Interestingly, proline accumulation significantly reduces the ROS level and increases the survival rate of yeast cells in the stationary phase under ethanol stress conditions. However, there was not a clear correlation between proline content and survival rate in yeast cells. An appropriate level of intracellular proline in yeast might be important for its stress-protective effect. Hence, the engineering of proline metabolism could be promising for breeding stress-tolerant industrial yeast strains. Copyright © 2016 John Wiley & Sons, Ltd.

Association study of PRODH gene variant rs385440 with schizophrenia in Zhuang and Han nationality of Guangxi

Objective To test the the association between PRODH gene variant rs385440 and the susceptibility to schizophrenia and the severity of schizophrenia in Guangxi Zhuang and Han population, further exploring the genetic mechanisms of schizophrenia in Guangxi Zhuang and Han population. Methods The schizophrenia patients were diagnosed according to ICD-10 criteria in this study. The subjects in the association analysis were 282 unrelated schizophrenia patients(94 Zhuang and 188 Han) and 282 healthy controls (94 Zhuang and 188 Han). A quantitative real-time PCR TaqMan MGB experimental method was carried out to analysis rs385440.The clinical psychotic symptoms of 246 schizophrenia patients(83 Zhuang and 163 Han) were assessed by PANSS.Statistical analyses were carried out with SPSS13.0 for windows. Results There was no statistically significant difference in different allele and genotype frequencies of rs385440 between schizophrenia cases and controls in Zhuang samples, Han samples and combined samples respectively(P>0.05). In Zhuang schizophrenia patients the score of N4(passive/apathetic social withdrawal) item in A allele carriers(3.28±1.34) was higher than that of G allele carriers(2.40±1.36) significantly(P<0.05), and the score of G12(lack of judgment and insight) item in A allele carriers(4.92±1.55) was higher than that of G allele carriers(4.12±1.85) significantly(P<0.05). Conclusion There is no association between PRODH gene variant rs385440 and the susceptibility to schizophrenia in Guangxi Zhuang and Han population. Rs385440 associated the severity of passive/apathetic social withdrawal symptom and poor attention symptom of schizophrenia in Zhuang. Key words: Schizophrenia; PRODH gene; rs385440; Association study; Zhuang nationality

Physiological and biochemical responses to the exogenous application of proline of tomato plants irrigated with saline water

In scope of crop salinity tolerance, an experiment was carried out in a field using saline water (6.57dSm−1) and subsurface drip irrigation (SDI) on two tomato cultivars (Solanum lycopersicum, cv. Rio Grande and Heinz-2274) in a salty clay soil. Exogenous application of proline was done by foliar spray at two concentrations: 10 and 20mgL−1, with a control (saline water without proline), during the flowering stage. Significant higher increases in proline and total soluble protein contents, glutamine synthetase (GS, EC6.3.1.2) activities and decreases in proline oxidase (l-proline: O2 Oxidoreductase, EC1.4.3.1) activities were detected in both tomato cultivars when irrigated with saline water (6.57dSm−1) and exogenously applied by the lower concentration of proline. Taking in consideration the obtained results, it was concluded that the foliar spray of low concentration of proline can increase the tolerance of both cultivars of tomato to salinity under field conditions.

Proline Oxidase (POX) as A Target for Cancer Therapy.

Proline dehydrogenase/proline oxidase (PRODH/POX) is an enzyme catalyzing the first step of proline degradation, during which ROS and/or ATP is generated. POX is widely distributed in living organisms and is responsible for a number of regulatory processes such as redox homeostasis, osmotic adaptation, cell signaling and oxidative stress. Recent data provided evidence that POX plays an important role in carcinogenesis and tumor growth. POX may induce apoptosis in both intrinsic and extrinsic way. Due to ROS generation, POX may induce caspase-9 activity, which mediates mitochondrial apoptosis (intrinsic apoptosis pathway). POX can also stimulate TRAIL (tumor necrosis factorrelated apoptosis inducing ligand) and DR5 (death receptor 5) expression, resulting in cleavage of procaspase-8 and thus extrinsic apoptotic pathway. However, this tumor suppressor in certain environmental conditions may act as a prosurvival factor. Genotoxic, inflammatory and metabolic stress may switch POX from tumor growth inhibiting to tumor growth supporting factor. The potential mechanisms which may regulate switching of POX mode are discussed in this review.

A Novel Role of Proline Oxidase in HIV-1 Envelope Glycoprotein-induced Neuronal Autophagy

Proline oxidase (POX) catalytically converts proline to pyrroline-5-carboxylate. This catabolic conversion generates reactive oxygen species (ROS) that triggers cellular signaling cascades including autophagy and apoptosis. This study for the first time demonstrates a role of POX in HIV-1 envelope glycoprotein (gp120)-induced neuronal autophagy. HIV-1 gp120 is a neurotoxic factor and is involved in HIV-1-associated neurological disorders. However, the mechanism of gp120-mediated neurotoxicity remains unclear. Using SH-SY5Y neuroblastoma cells as a model, this study demonstrates that gp120 treatment induced POX expression and catalytic activity. Concurrently, gp120 also increased intracellular ROS levels. However, increased ROS had a minimal effect on neuronal apoptosis. Further investigation indicated that the immediate cellular response to increased ROS paralleled with induction of autophagy markers, beclin-1 and LC3-II. These data lead to the hypothesis that neuronal autophagy is activated as a cellular protective response to the toxic effects of gp120. A direct and functional role of POX in gp120-mediated neuronal autophagy was examined by inhibition and overexpression studies. Inhibition of POX activity by a competitive inhibitor "dehydroproline" decreased ROS levels concomitant with reduced neuronal autophagy. Conversely, overexpression of POX in neuronal cells increased ROS levels and activated ROS-dependent autophagy. Mechanistic studies suggest that gp120 induces POX by targeting p53. Luciferase reporter assays confirm that p53 drives POX transcription. Furthermore, data demonstrate that gp120 induces p53 via binding to the CXCR4 co-receptor. Collectively, these results demonstrate a novel role of POX as a stress response metabolic regulator in HIV-1 gp120-associated neuronal autophagy.

Effect of proline supplementation on anti-oxidative capacity, immune response and stress tolerance of juvenile Pacific white shrimp, Litopenaeus vannamei

Abstract An 8-week feeding trial was conducted to evaluate the effect of proline on anti-oxidative capacity, immune response and stress tolerance of juvenile Pacific white shrimp, Litopenaeus vannamei . Six practical low fishmeal diets (15% fishmeal) were formulated to contain graded levels (2.02, 2.14, 2.27, 2.38, 2.49, 2.6%) of l -proline. Each diet was randomly assigned to triplicate groups of 30 shrimps (approximately 0.41 g) and the shrimps were fed 4 times a day to apparent satiation. Growth performance was not affected by proline levels (P > 0.05). But higher levels of proline increased hydroxyproline content in the whole body (P = 0.004). And survival after 60 h acute NH 3 stress increased with the increasing dietary proline levels (P = 0.015). High levels of proline also increased the proline oxidase (POX), nitric oxide (NO), total antioxidant capacity (T-AOC) and phenoloxidase (PO) activities in hemolymph or hepatopancreas after the 60 h NH 3 stress compared to basic group which had lowest proline level. Broken-line analysis showed that the optimal dietary proline requirement of L. vannamei was 2.29%, 2.32% and 2.34% based on PO, POX and 60 h survival after NH 3 stress. These results clearly indicated that 2.29–2.34% of proline in the low fish meal diet could improve anti-oxidative capacity, immune response, NH 3 stress tolerance of L. vannamei , and proline may be a conditionally essential AA for L. vannamei . Statement of relevance This study indicates that proline may be a conditional amino acid for white shrimp under the environment stress, especially when fed with low fish meal diet. The results will contribute to the low fish meal diet study of the white shrimp.

Arabidopsis AtbHLH112 regulates the expression of genes involved in abiotic stress tolerance by binding to their E-box and GCG-box motifs.

Plant basic helix-loop-helix (bHLH) transcription factors play essential roles in abiotic stress tolerance. However, most bHLHs have not been functionally characterized. Here, we characterized the functional role of a bHLH transcription factor from Arabidopsis, AtbHLH112, in response to abiotic stress. AtbHLH112 is a nuclear-localized protein, and its nuclear localization is induced by salt, drought and abscisic acid (ABA). In addition, AtbHLH112 serves as a transcriptional activator, with the activation domain located at its N-terminus. In addition to binding to the E-box motifs of stress-responsive genes, AtbHLH112 binds to a novel motif with the sequence 'GG[GT]CC[GT][GA][TA]C' (GCG-box). Gain- and loss-of-function analyses showed that the transcript level of AtbHLH112 is positively correlated with salt and drought tolerance. AtbHLH112 mediates stress tolerance by increasing the expression of P5CS genes and reducing the expression of P5CDH and ProDH genes to increase proline levels. AtbHLH112 also increases the expression of POD and SOD genes to improve reactive oxygen species (ROS) scavenging ability. We present a model suggesting that AtbHLH112 is a transcriptional activator that regulates the expression of genes via binding to their GCG- or E-boxes to mediate physiological responses, including proline biosynthesis and ROS scavenging pathways, to enhance stress tolerance.

Salicylic acid supplementation improves photosynthesis and growth in mustard through changes in proline accumulation and ethylene formation under drought stress

Drought stress is becoming a major threat to plant productivity loss in agricultural system. The present study was carried out to evaluate the physiological and biochemical alterations induced by salicylic acid (SA) in mustard plant under moderate drought stress conditions. Therefore, a pot culture experiment was conducted to test whether SA application at concentration of 0.5mM through foliar spray could protect the mustard (Brassica juncea L.) cultivar Pusa Jai Kisan subjected to drought stress on the basis of growth and photosynthesis. The treatments were as follows: (i) 100% FC+0mM SA, (ii) 50% FC+0mM SA, (iii) 100% FC+0.5mM SA and (iv) 50% FC+0.5mM SA. The control treatment received 100% field capacity (FC) irrigation, whereas moderate drought stress corresponded to 50% field capacity. Plants subjected to drought stress caused significant reduction in growth and photosynthetic parameters, activity of ribulose 1,5-bisphosphate carboxylase (Rubisco), nitrate reductase (NR), ATP-sulfurylase (ATPS) which accounted for decreased nitrogen (N) and sulfur (S) assimilation. Whereas, a pronounced increase was observed in proline metabolism. Exogenously applied 0.5mM SA alleviated the stress by increasing the proline production through the increase in γ-glutamyl kinase (GK) and decrease in proline oxidase (PROX) activity. In addition SA application restricted the ethylene formation by inhibiting the 1-aminocyclopropane carboxylic acid synthase (ACS) activity more conspicuously under moderate drought stress than no stress. These findings reflect that SA application alleviates the drought-induced decrease in growth and photosynthesis through increased proline content. Higher proline content was a result of increased N and S assimilation and increased synthesis of proline synthesizing enzyme which lowers the oxidative stress in mustard.

DGCR6 at the proximal part of the DiGeorge critical region is involved in conotruncal heart defects.

Cardiac anomaly is one of the hallmarks of DiGeorge syndrome (DGS), observed in approximately 80% of patients. It often shows a characteristic morphology, termed as conotruncal heart defects. In many cases showing only the conotruncal heart defect, deletion of 22q11.2 region cannot be detected by fluorescence in situ hybridization (FISH), which is used to detect deletion in DGS. We investigated the presence of genomic aberrations in six patients with congenital conotruncal heart defects, who show no deletion at 22q11.2 in an initial screening by FISH. In these patients, no abnormalities were identified in the coding region of the TBX1 gene, one of the key genes responsible for the phenotype of DGS. However, when copy number alteration was analyzed by high-resolution array analysis, a small deletion or duplication in the proximal end of DiGeorge critical region was detected in two patients. The affected region contains the DGCR6 and PRODH genes. DGCR6 has been reported to affect the expression of the TBX1 gene. Our results suggest that altered dosage of gene(s) other than TBX1, possibly DGCR6, may also be responsible for the development of conotruncal heart defects observed in patients with DGS and, in particular, in those with stand-alone conotruncal heart defects.

Changes in Proline and Polyphenol oxidase enzyme activity in some Banana Cultivars and Hybrids under water stress

Plant growth and productivity is adversely affected by abiotic stresses induced changes in proline content and polyphenol oxidase enzyme activity. Field experiments were conducted at the National Research Centre for banana, Thiruchirapalli, during the growing season of 2011-2013 to compare the changes in proline content and PPO enzyme activity in twelve main crop and ratoon crop ofbanana cultivars and hybrids in 5 th and 7 th MAP (Month after Planting) under t wo levels of irrigation. The lowest reduction in the bunch yield of tolerant banana cultivars and hybrids viz., Karpuravalli, Karpuravalli x PisangJajee, Saba, and Sannachenkathali with the highest increase in proline and PPO enzyme activity was observed in 5 th and 7 th MAP stage due to 50 per cent depletion in available soil moisture (ASM) of the stress.

Selenium and sulfur influence ethylene formation and alleviate cadmium-induced oxidative stress by improving proline and glutathione production in wheat

We have studied the influence of selenium (Se) and sulfur (S) in the protection of photosynthetic capacity of wheat (Triticum aestivum) against cadmium (Cd) stress. The involvement of ethylene and its interaction with proline and antioxidant metabolism in the tolerance of plants to Cd stress was evaluated. Application of Se or S alleviated Cd-induced oxidative stress by increasing proline accumulation as a result of increased activity of glutamyl kinase (GK) and decreased activity of proline oxidase (PROX). These nutrients also induced the activity of ATP-sulfurylase and serine acetyl transferase and the content of cysteine (Cys), a precursor for the synthesis of both reduced glutathione (GSH) and ethylene. Further, application of Se and S to plants under Cd stress reduced ethylene level and increased the activity of glutathione reductase (GR) and glutathione peroxidase (GPX), reduced oxidative stress and improved photosynthesis and growth. The involvement of ethylene in Se and S-mediated alleviation of Cd stress was substantiated with the use of ethylene biosynthesis inhibitor aminoethoxyvinylglycine (AVG). The use of AVG reversed the effects of Se and S on ethylene, content of proline and GSH and photosynthesis. The results suggested that Se and S both reversed Cd-induced oxidative stress by regulating ethylene formation, proline and GSH metabolism. Thus, Se or S-induced regulatory interaction between ethylene and proline and GSH metabolism may be used for the reversal of Cd-induced oxidative stress.

Tacrolimus(FK506) Induced Cytotoxicity Via TRAIL-R1 (DR4) or TRAIL-R2 (DR5) in Jurkat Cells.

Purpose: To elucidate the mechanism of Tacrolimus(FK506) induced cytotoxicity via TRAIL(TNF related apoptosis inducing ligand)-R1(DR4) and TRAIL-R2(DR5) in FK506-treated Jurkat T cells. And signal transduction pathway of TNF-related events was studied. Methods: Viability of Jurkat T cells was measure by MTT assay. The catalytic activation of caspase-3 and caspase-9 proteases was determined by digestion of fluorogenic biosubstrates and western blot with anti-caspase-3 and anti-caspase-9 antibodies. The levels of mRNA and proteins for p53, Bax, PUMA, proline oxidase, TRAIL(TNF related apoptosis inducing ligand), TRAIL-R1(DR4), TRAIL-R2(DR5), Fas, FasL, TNF-α, IL-6, and NKκB were measured by RT-PCR and western blot with specific antibodies. Also we further examined the localization of TRAIL family proteins using by fluorescent microscope with specific TRAIL family antibodies. Results: FK506 decreased the viability of Jurkat T cells dose- and time-dependently along with catalytic activation of caspase-3 and caspase-9, p53 phosphorylation, and changes in expression levels of Bax, PUMA, and proline oxidase protein. It caused an increase in expression of TRAIL, TRAIL-R1(DR4), TRAIL-R2(DR5), Fas, and FasL in the levels of mRNA and proteins of Jurkat T cells. Furthermore, FK506 increased extracellular release of TNF-α and IL-6 cytokines in Jurkat T cells. It also induced the transactivation of NKκB through the dephosphrylation of Ser486 residues in Jurkat t cells. Conclusion: These results suggest that FK506 induces apoptotic death of Jurkat cells through activation of caspase family protease, Bcl-2 family protein-related mitochondrial dysfunction, and activation of death-receptor mediated signaling pathways.

Association of COMT and PRODH gene variants with intelligence quotient (IQ) and executive functions in 22q11.2DS subjects

The 22q11.2 deletion syndrome (22q11.2DS) carries the highest genetic risk factor for the development of schizophrenia. We investigated the association of genetic variants in two schizophrenia candidate genes with executive function (EF) and IQ in 22q11.2DS individuals.Ninety two individuals with 22q11.2 deletion were studied for the genetic association between COMT and PRODH variants and EF and IQ. Subjects were divided into children (under 12 years old), adolescents (between 12 and 18 years old) and adults (older than 18 years), and genotyped for the COMT Val158Met (rs4680) and PRODH Arg185Trp (rs4819756) polymorphisms. The participants underwent psychiatric evaluation and EF assessment. Our main finding is a significant influence of the COMT Val158Met polymorphism on both IQ and EF performance. Specifically, 22q11.2DS subjects with Met allele displayed higher IQ scores in all age groups compared to Val carriers, reaching significance in both adolescents and adults. The Met allele carriers performed better than Val carriers in EF tasks, being statistically significant in the adult group. PRODH Arg185Trp variant did not affect IQ or EF in our 22q11.2DS cohort. In conclusion, functional COMT variant, but not PRODH, affects IQ and EF in 22q11.2DS subjects during neurodevelopment with a maximal effect at adulthood. Future studies should monitor the cognitive performance of the same individuals from childhood to old age.

Involvement of proline oxidase (PutA) in programmed cell death of Xanthomonas.

Xanthomonas campestris strains have been reported to undergo programmed cell death (PCD) in a protein rich medium. Protein hydrolysates used in media such as nutrient broth comprise of casein digest with abundance of proline and glutamate. In the current study, X. campestris pv. campestris (Xcc) cells displayed PCD when grown in PCD inducing medium (PIM) containing casein tryptic digest. This PCD was also observed in PCD non-inducing carbohydrate rich medium (PNIM) fortified with either proline or proline along with glutamate. Surprisingly, no PCD was noticed in PNIM fortified with glutamate alone. Differential role of proline or glutamate in inducing PCD in Xcc cells growing in PNIM was studied. It was found that an intermediate product of this oxidation was involved in initiation of PCD. Proline oxidase also called as proline utilization A (PutA), catalyzes the two step oxidation of proline to glutamate. Interestingly, higher PutA activity was noticed in cells growing in PIM, and PCD was found to be inhibited by tetrahydro-2-furoic acid, a competitive inhibitor of this enzyme. Further, PCD was abolished in Xcc ΔputA strain generated using a pKNOCK suicide plasmid, and restored in Xcc ΔputA strain carrying functional PutA in a plasmid vector. Xanthomonas cells growing in PIM also displayed increased generation of ROS, as well as cell filamentation (a probable indication of SOS response). These filamented cells also displayed enhanced caspase-3-like activity during in situ labeling using a fluorescent tagged caspase-3 inhibitor (FITC-DEVD-FMK). The extent of PCD associated markers such as DNA damage, phosphatidylserine externalization and membrane depolarization were found to be significantly enhanced in wild type cells, but drastically reduced in Xcc ΔputA cells. These findings thus establish the role of PutA mediated proline oxidation in regulating death in stressed Xanthomonas cells.

Vitamin D insufficiency and schizophrenia risk: Evaluation of hyperprolinemia as a mediator of association

25-Hydroxyvitamin D (25(OH)D) deficits have been associated with schizophrenia susceptibility and supplementation has been recommended for those at-risk. Although the mechanism by which a deficit confers risk is unknown, vitamin D is a potent transcriptional modulator and can regulate proline dehydrogenase (PRODH) expression. PRODH maps to chromosome 22q11, a region conferring the highest known genetic risk of schizophrenia, and encodes proline oxidase, which catalyzes proline catabolism. l-Proline is a neuromodulator at glutamatergic synapses, and peripheral hyperprolinemia has been associated with decreased IQ, cognitive impairment, schizoaffective disorder, and schizophrenia.We investigated the relationship between 25(OH)D and schizophrenia, comparing fasting plasma 25(OH)D in 64 patients and 90 matched controls. We then tested for a mediating effect of hyperprolinemia on the association between 25(OH)D and schizophrenia.25(OH)D levels were significantly lower in patients, and 25(OH)D insufficiency associated with schizophrenia (OR 2.1, adjusted p=0.044, 95% CI: 1.02–4.46). Moreover, 25(OH)D insufficient subjects had three times greater odds of hyperprolinemia than those with optimal levels (p=0.035, 95% CI: 1.08–8.91), and formal testing established that hyperprolinemia is a significantly mediating phenotype that may explain over a third of the effect of 25(OH)D insufficiency on schizophrenia risk.This study presents a mechanism by which 25(OH)D insufficiency confers risk of schizophrenia; via proline elevation due to reduced PRODH expression, and a concomitant dysregulation of neurotransmission. Although definitive causality cannot be confirmed, these findings strongly support vitamin D supplementation in patients, particularly for those with elevated proline, who may represent a large subgroup of the schizophrenia population.

PRODH Polymorphisms, Cortical Volumes and Thickness in Schizophrenia

Schizophrenia is a neurodevelopmental disorder with high heritability. Several lines of evidence indicate that the PRODH gene may be related to the disorder. Therefore, our study investigates the effects of 12 polymorphisms of PRODH on schizophrenia and its phenotypes. To further evaluate the roles of the associated variants in the disorder, we have conducted magnetic resonance imaging (MRI) scans to assess cortical volumes and thicknesses. A total of 192 patients were evaluated using the Structured Clinical Interview for DSM-IV (SCID), Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale, Global Assessment of Functioning (GAF) and Clinical Global Impression (CGI) instruments. The study included 179 controls paired by age and gender. The samples were genotyped using the real-time polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP)-PCR and Sanger sequencing methods. A sample of 138 patients and 34 healthy controls underwent MRI scans. One polymorphism was associated with schizophrenia (rs2904552), with the G-allele more frequent in patients than in controls. This polymorphism is likely functional, as predicted by PolyPhen and SIFT, but it was not associated with brain morphology in our study. In summary, we report a functional PRODH variant associated with schizophrenia that may have a neurochemical impact, altering brain function, but is not responsible for the cortical reductions found in the disorder.

播种期对晚季香稻香气2-乙酰-1-吡咯啉含量和产量的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 播种期对晚季香稻香气2-乙酰-1-吡咯啉含量和产量的影响 DOI: 10.5846/stxb201305211129 作者: 作者单位: 华南农业大学农学院,华南农业大学农学院,华南农业大学农学院,华南农业大学农学院,华南农业大学农学院,华南农业大学农学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31271646）；广东省自然科学基金项目（8151064201000017）；广东省农业攻关项目（2011AO20202001）；广东省农业标准化项目（4100F10003） Effects of sowing date on 2-acetyl-1-pyrroline content and yield of late season aromatic rice Author: Affiliation: College of Agriculture,South China Agricultural University,College of Agriculture,South China Agricultural University,College of Agriculture,South China Agricultural University,College of Agriculture,South China Agricultural University,College of Agriculture,South China Agricultural University, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为了确定华南双季稻区晚季香稻的适宜播种期，在大田条件下以桂香占和农香18为材料，研究了播种期对香稻香气2-乙酰-1-吡咯啉（2-AP）、脯氨酸代谢酶活性和产量的影响。结果表明：（1）7月20日播种的香稻的2-AP含量最高，2-AP含量较高的播期其游离脯氨酸含量、籽粒脯氨酸氧化酶活性以及脯氨酸脱氢酶活性维持在较高水平。（2）7月15日播种的桂香占和7月20日播种的农香18的产量最高，产量较高的播期具有较高的收获指数、干物质积累量和群体生长率。（3）试验条件下晚季香稻的适宜播种期为7月15日-7月20日。 Abstract:Aromatic rice, a famous rice type with high nutritional value and a distinct aroma, has been planted in South and Southeast Asian countries since ancient times. Recently, it has gained in popularity and gained a significant market share in the global rice trade resulting in higher prices and increased production in many countries. However, in China, a minimal area has been planted with aromatic rice because of its low resistance to disease, low yield and other disadvantages of the aromatic rice cultivars. As the standard of living has improved, China has begun to focus on the production of quality food, so researchers have started to pay more attention to aromatic rice and have bred some aromatic rice cultivars. However, finding ways to increase the concentration of the aroma of aromatic rice has proved challenging based on the low yield and poor quality of existing cultivars. 2-Acetyl-1-pyrroline (2-AP) is a buttered-popcorn-like aromatic compound found in both basmati and jasmine aromatic rice, and is considered a primary aromatic component of aromatic rice; this highly volatile and lipophilic compound occurs in the stems, leaves and grains of aromatic rice. L-proline is widely considered to be the nitrogen source for 2-AP and Δ-pyrroline-5-carboxylic acid (P5C) and has been proposed as one of the main precursors required for 2-AP synthesis. P5C is the common intermediate in the metabolic pathways of proline, ornithine and glutamic acid synthesis. Among these three pathways, the proline pathway is the major pathway used for the synthesis of 2-AP, in which proline to P5C is mediated by proline dehydrogenase, which is then used to synthetize 2-AP. Genetic factors play a major role in determining the aroma content of aromatic rice, and environmental factors and cultivation practices have a substantial effect on the quality of aromatic rice. The aroma of aromatic rice can be increased using low-density cultivation techniques, shallow irrigation, low levels of nitrogen, and moderate use of trace element fertilizers containing elements such as zinc, iron and lanthanum. However, unsuitable post-harvest conditions and some plant growth regulators can reduce the 2-AP content in aromatic rice considerably. Using better packaging materials, such as vacuum packing in nylon pouches, can retard volatilization of the aromatic compounds in aromatic rice. Temperature during grain filling, ripening and storage also plays an important role in the development of the aroma of aromatic rice; lower temperature, especially at night, has positive effects on aroma formation during the grain filling and ripening stages compared with higher temperature. Additionally, 2-AP content declines over time and is significantly affected by the temperature during storage. The sowing date affects proline and 2-AP content in aromatic rice as a result of variations in light and temperature conditions. Hence, a field experiment was carried out using Guixiangzhan and Nongxiang18 cultivars to determine an appropriate sowing date for late season aromatic rice in South China's double-cropping region and to study the effects of different sowing dates on aroma (2-AP), activities of proline metabolic enzymes and yield. The results show (1) Aromatic rice sown on 20 July achieved the highest 2-AP content. Treatments having higher 2-AP content also had a higher free proline content, higher proline oxidase activities in grain and higher levels of proline dehydrogenase. (2) Guixiangzhan sown on 15 July and Nongxiang18 sown on 20 July achieved the highest grain yield, and both had a high harvest index, high levels of dry matter accumulation and rapid crop growth rates. (3) The appropriate late season sowing date for aromatic rice was between 15 July and 20 July. 参考文献 相似文献 引证文献