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[PMID]:26754668
[Au] Autor:Cakir B; Shiraishi S; Tuncel A; Matsusaka H; Satoh R; Singh S; Crofts N; Hosaka Y; Fujita N; Hwang SK; Satoh H; Okita TW
[Ad] Endereço:Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164 (B.C., A.T., S.-K.H., T.W.O.);Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (S.Sh., H.M., R.S., H.S.);Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat-785013,
[Ti] Título:Analysis of the Rice ADP-Glucose Transporter (OsBT1) Indicates the Presence of Regulatory Processes in the Amyloplast Stroma That Control ADP-Glucose Flux into Starch.
[So] Source:Plant Physiol;170(3):1271-83, 2016 Mar.
[Is] ISSN:1532-2548
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Previous studies showed that efforts to further elevate starch synthesis in rice (Oryza sativa) seeds overproducing ADP-glucose (ADPglc) were prevented by processes downstream of ADPglc synthesis. Here, we identified the major ADPglc transporter by studying the shrunken3 locus of the EM1093 rice line, which harbors a mutation in the BRITTLE1 (BT1) adenylate transporter (OsBt1) gene. Despite containing elevated ADPglc levels (approximately 10-fold) compared with the wild-type, EM1093 grains are small and shriveled due to the reduction in the amounts and size of starch granules. Increases in ADPglc levels in EM1093 were due to their poor uptake of ADP-[(14)C]glc by amyloplasts. To assess the potential role of BT1 as a rate-determining step in starch biosynthesis, the maize ZmBt1 gene was overexpressed in the wild-type and the GlgC (CS8) transgenic line expressing a bacterial glgC-TM gene. ADPglc transport assays indicated that transgenic lines expressing ZmBT1 alone or combined with GlgC exhibited higher rates of transport (approximately 2-fold), with the GlgC (CS8) and GlgC/ZmBT1 (CS8/AT5) lines showing elevated ADPglc levels in amyloplasts. These increases, however, did not lead to further enhancement in seed weights even when these plant lines were grown under elevated CO2. Overall, our results indicate that rice lines with enhanced ADPglc synthesis and import into amyloplasts reveal additional barriers within the stroma that restrict maximum carbon flow into starch.
[Mh] Termos MeSH primário: Adenosina Difosfato Glucose/metabolismo
Proteínas Facilitadoras de Transporte de Glucose/metabolismo
Oryza/metabolismo
Proteínas de Plantas/metabolismo
Amido/metabolismo
[Mh] Termos MeSH secundário: Genes de Plantas
Proteínas Facilitadoras de Transporte de Glucose/genética
Mutação
Oryza/genética
Proteínas de Plantas/genética
Plantas Geneticamente Modificadas
Plastídeos/metabolismo
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Sementes/metabolismo
Zea mays/enzimologia
Zea mays/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Glucose Transport Proteins, Facilitative); 0 (Plant Proteins); 0 (Recombinant Proteins); 2140-58-1 (Adenosine Diphosphate Glucose); 9005-25-8 (Starch)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160113
[St] Status:MEDLINE
[do] DOI:10.1104/pp.15.01911


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[PMID]:25717036
[Au] Autor:Morita R; Sugino M; Hatanaka T; Misoo S; Fukayama H
[Ad] Endereço:Laboratory of Crop Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan.
[Ti] Título:CO2-responsive CONSTANS, CONSTANS-like, and time of chlorophyll a/b binding protein Expression1 protein is a positive regulator of starch synthesis in vegetative organs of rice.
[So] Source:Plant Physiol;167(4):1321-31, 2015 Apr.
[Is] ISSN:1532-2548
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A unique CO2-Responsive CONSTANS, CONSTANS-like, and Time of Chlorophyll a/b Binding Protein1 (CCT) Protein (CRCT) containing a CCT domain but not a zinc finger motif is described, which is up-regulated under elevated CO2 in rice (Oryza sativa). The expression of CRCT showed diurnal oscillation peaked at the end of the light period and was also increased by sugars such as glucose and sucrose. Promoter ß-glucuronidase analysis showed that CRCT was highly expressed in the phloem of various tissues such as leaf blade and leaf sheath. Overexpression or RNA interference knockdown of CRCT had no appreciable effect on plant growth and photosynthesis except that tiller angle was significantly increased by the overexpression. More importantly, starch content in leaf sheath, which serves as a temporary storage organ for photoassimilates, was markedly increased in overexpression lines and decreased in knockdown lines. The expressions of several genes related to starch synthesis, such as ADP-glucose pyrophospholylase and α-glucan phospholylase, were significantly changed in transgenic lines and positively correlated with the expression levels of CRCT. Given these observations, we suggest that CRCT is a positive regulator of starch accumulation in vegetative tissues, regulating coordinated expression of starch synthesis genes in response to the levels of photoassimilates.
[Mh] Termos MeSH primário: Dióxido de Carbono/metabolismo
Regulação da Expressão Gênica de Plantas
Oryza/metabolismo
Proteínas de Plantas/metabolismo
Amido/metabolismo
[Mh] Termos MeSH secundário: Adenosina Difosfato Glucose/metabolismo
Metabolismo dos Carboidratos
Clorofila/metabolismo
Expressão Gênica
Técnicas de Silenciamento de Genes
Glucose-1-Fosfato Adenililtransferase/genética
Glucose-1-Fosfato Adenililtransferase/metabolismo
Glucuronidase/genética
Glucuronidase/metabolismo
Análise de Sequência com Séries de Oligonucleotídeos
Especificidade de Órgãos
Oryza/citologia
Oryza/genética
Floema/citologia
Floema/genética
Floema/metabolismo
Fosforilases/genética
Fosforilases/metabolismo
Fotossíntese
Folhas de Planta/citologia
Folhas de Planta/genética
Folhas de Planta/metabolismo
Proteínas de Plantas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Plant Proteins); 1406-65-1 (Chlorophyll); 142M471B3J (Carbon Dioxide); 2140-58-1 (Adenosine Diphosphate Glucose); 5712ZB110R (chlorophyll b); 9005-25-8 (Starch); EC 2.4.1.- (Phosphorylases); EC 2.7.7.27 (Glucose-1-Phosphate Adenylyltransferase); EC 3.2.1.31 (Glucuronidase); YF5Q9EJC8Y (chlorophyll a)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150227
[St] Status:MEDLINE
[do] DOI:10.1104/pp.15.00021


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[PMID]:25666133
[Au] Autor:Clermont L; Macha A; Müller LM; Derya SM; von Zaluskowski P; Eck A; Eikmanns BJ; Seibold GM
[Ad] Endereço:Institute of Biochemistry, University of Cologne, Cologne, Germany.
[Ti] Título:The α-glucan phosphorylase MalP of Corynebacterium glutamicum is subject to transcriptional regulation and competitive inhibition by ADP-glucose.
[So] Source:J Bacteriol;197(8):1394-407, 2015 Apr.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:UNLABELLED: α-Glucan phosphorylases contribute to degradation of glycogen and maltodextrins formed in the course of maltose metabolism in bacteria. Accordingly, bacterial α-glucan phosphorylases are classified as either glycogen or maltodextrin phosphorylase, GlgP or MalP, respectively. GlgP and MalP enzymes follow the same catalytic mechanism, and thus their substrate spectra overlap; however, they differ in their regulation: GlgP genes are constitutively expressed and the enzymes are controlled on the activity level, whereas expression of MalP genes are transcriptionally controlled in response to the carbon source used for cultivation. We characterize here the modes of control of the α-glucan phosphorylase MalP of the Gram-positive Corynebacterium glutamicum. In accordance to the proposed function of the malP gene product as MalP, we found transcription of malP to be regulated in response to the carbon source. Moreover, malP transcription is shown to depend on the growth phase and to occur independently of the cell glycogen content. Surprisingly, we also found MalP activity to be tightly regulated competitively by the presence of ADP-glucose, an intermediate of glycogen synthesis. Since the latter is considered a typical feature of GlgPs, we propose that C. glutamicum MalP acts as both maltodextrin and glycogen phosphorylase and, based on these findings, we question the current system for classification of bacterial α-glucan phosphorylases. IMPORTANCE: Bacterial α-glucan phosphorylases have been classified conferring to their purpose as either glycogen or maltodextrin phosphorylases. We found transcription of malP in C. glutamicum to be regulated in response to the carbon source, which is recognized as typical for maltodextrin phosphorylases. Surprisingly, we also found MalP activity to be tightly regulated competitively by the presence of ADP-glucose, an intermediate of glycogen synthesis. The latter is considered a typical feature of GlgPs. These findings, taken together, suggest that C. glutamicum MalP is the first α-glucan phosphorylase that does not fit into the current system for classification of bacterial α-glucan phosphorylases and exemplifies the complex mechanisms underlying the control of glycogen content and maltose metabolism in this model organism.
[Mh] Termos MeSH primário: Adenosina Difosfato Glucose/metabolismo
Corynebacterium glutamicum/enzimologia
Regulação Bacteriana da Expressão Gênica/fisiologia
Regulação Enzimológica da Expressão Gênica/fisiologia
Fosforilases/metabolismo
Transcrição Genética/fisiologia
[Mh] Termos MeSH secundário: Corynebacterium glutamicum/genética
Corynebacterium glutamicum/metabolismo
Fosforilases/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
2140-58-1 (Adenosine Diphosphate Glucose); EC 2.4.1.- (Phosphorylases)
[Em] Mês de entrada:1506
[Cu] Atualização por classe:151028
[Lr] Data última revisão:
151028
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150211
[St] Status:MEDLINE
[do] DOI:10.1128/JB.02395-14


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[PMID]:25133777
[Au] Autor:Bahaji A; Baroja-Fernández E; Sánchez-López AM; Muñoz FJ; Li J; Almagro G; Montero M; Pujol P; Galarza R; Kaneko K; Oikawa K; Wada K; Mitsui T; Pozueta-Romero J
[Ad] Endereço:Instituto de Agrobiotecnología, Universidad Pública de Navarra/Consejo Superior de Investigaciones Científicas/Gobierno de Navarra, Mutiloabeti, Nafarroa, Spain.
[Ti] Título:HPLC-MS/MS analyses show that the near-Starchless aps1 and pgm leaves accumulate wild type levels of ADPglucose: further evidence for the occurrence of important ADPglucose biosynthetic pathway(s) alternative to the pPGI-pPGM-AGP pathway.
[So] Source:PLoS One;9(8):e104997, 2014.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In leaves, it is widely assumed that starch is the end-product of a metabolic pathway exclusively taking place in the chloroplast that (a) involves plastidic phosphoglucomutase (pPGM), ADPglucose (ADPG) pyrophosphorylase (AGP) and starch synthase (SS), and (b) is linked to the Calvin-Benson cycle by means of the plastidic phosphoglucose isomerase (pPGI). This view also implies that AGP is the sole enzyme producing the starch precursor molecule, ADPG. However, mounting evidence has been compiled pointing to the occurrence of important sources, other than the pPGI-pPGM-AGP pathway, of ADPG. To further explore this possibility, in this work two independent laboratories have carried out HPLC-MS/MS analyses of ADPG content in leaves of the near-starchless pgm and aps1 mutants impaired in pPGM and AGP, respectively, and in leaves of double aps1/pgm mutants grown under two different culture conditions. We also measured the ADPG content in wild type (WT) and aps1 leaves expressing in the plastid two different ADPG cleaving enzymes, and in aps1 leaves expressing in the plastid GlgC, a bacterial AGP. Furthermore, we measured the ADPG content in ss3/ss4/aps1 mutants impaired in starch granule initiation and chloroplastic ADPG synthesis. We found that, irrespective of their starch contents, pgm and aps1 leaves, WT and aps1 leaves expressing in the plastid ADPG cleaving enzymes, and aps1 leaves expressing in the plastid GlgC accumulate WT ADPG content. In clear contrast, ss3/ss4/aps1 leaves accumulated ca. 300 fold-more ADPG than WT leaves. The overall data showed that, in Arabidopsis leaves, (a) there are important ADPG biosynthetic pathways, other than the pPGI-pPGM-AGP pathway, (b) pPGM and AGP are not major determinants of intracellular ADPG content, and (c) the contribution of the chloroplastic ADPG pool to the total ADPG pool is low.
[Mh] Termos MeSH primário: Adenosina Difosfato Glucose/metabolismo
Proteínas de Arabidopsis/metabolismo
Cromatografia Líquida de Alta Pressão
Glucose-1-Fosfato Adenililtransferase/metabolismo
Folhas de Planta/enzimologia
Folhas de Planta/metabolismo
Sintase do Amido/metabolismo
Espectrometria de Massas em Tandem
[Mh] Termos MeSH secundário: Arabidopsis/enzimologia
Arabidopsis/metabolismo
Proteínas de Arabidopsis/genética
Glucose-1-Fosfato Adenililtransferase/genética
Glucose-6-Fosfato Isomerase
Plastídeos/enzimologia
Plastídeos/metabolismo
Sintase do Amido/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Arabidopsis Proteins); 2140-58-1 (Adenosine Diphosphate Glucose); EC 2.4.1.21 (Starch Synthase); EC 2.7.7.27 (Glucose-1-Phosphate Adenylyltransferase); EC 5.3.1.9 (Glucose-6-Phosphate Isomerase)
[Em] Mês de entrada:1504
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140819
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0104997


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[PMID]:25052102
[Au] Autor:Liu D; Wang W; Cai X
[Ad] Endereço:National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China; Graduate School of the Chinese Academy of Sciences, Beijing, China.
[Ti] Título:Modulation of amylose content by structure-based modification of OsGBSS1 activity in rice (Oryza sativa L.).
[So] Source:Plant Biotechnol J;12(9):1297-307, 2014 Dec.
[Is] ISSN:1467-7652
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The rice Waxy (Wx) gene encodes granule-bound starch synthase 1 (EC 2.4.1.242), OsGBSS1, which is responsible for amylose synthesis in rice seed endosperm. In this study, we determined the functional contribution of eight amino acids on the activity of OsGBSS1 by introducing site-directed mutated Wx gene constructs into the wx mutant glutinous rice. The eight amino acid residues are suspected to play roles in OsGBSS1 structure maintenance or function based on homologous enzyme sequence alignment and homology modelling. Both OsGBSS1 activity and amylose content were analysed in homozygous transgenic lines carrying the mutated OsGBSS1 (Wx) genes. Our results indicate that mutations at diverse sites in OsGBSS1 reduces its activity by affecting its starch-binding capacity, its ADP-glucose-binding capability or its protein stability. Our results shed new light on the structural basis of OsGBSS1 activity and the mechanisms of OsGBSS1 activity on amylose synthesis in vivo. This study also demonstrates that it is feasible to finely modulate amylose content in rice grains by modifying the OsGBSS1 activity.
[Mh] Termos MeSH primário: Amilose/metabolismo
Oryza/enzimologia
Proteínas de Plantas/química
Proteínas de Plantas/genética
Sintase do Amido/química
Sintase do Amido/genética
[Mh] Termos MeSH secundário: Adenosina Difosfato Glucose/metabolismo
Sequência de Aminoácidos
Substituição de Aminoácidos
Cruzamentos Genéticos
Regulação da Expressão Gênica de Plantas
Homozigoto
Cinética
Dados de Sequência Molecular
Mutagênese Sítio-Dirigida
Mutação/genética
Oryza/genética
Proteínas de Plantas/metabolismo
Plantas Geneticamente Modificadas
Plasmídeos/metabolismo
Ligação Proteica
Estabilidade Proteica
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Proteínas Recombinantes/metabolismo
Sintase do Amido/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Plant Proteins); 0 (RNA, Messenger); 0 (Recombinant Proteins); 2140-58-1 (Adenosine Diphosphate Glucose); 9005-82-7 (Amylose); EC 2.4.1.21 (Starch Synthase)
[Em] Mês de entrada:1507
[Cu] Atualização por classe:151119
[Lr] Data última revisão:
151119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140724
[St] Status:MEDLINE
[do] DOI:10.1111/pbi.12228


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[PMID]:24508535
[Au] Autor:Gao Y; Jiang Y; Liu Q; Wang R; Liu X; Liu B
[Ad] Endereço:College of Food and Bioengineering, Qilu University of Technology, Jinan, Shandong 250353, PR China.
[Ti] Título:Enzymatic and regulatory properties of the trehalose-6-phosphate synthase from the thermoacidophilic archaeon Thermoplasma acidophilum.
[So] Source:Biochimie;101:215-20, 2014 Jun.
[Is] ISSN:1638-6183
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:Trehalose-6-phosphate synthase plays an important role in trehalose metabolism. It catalyzes the transfer of glucose from UDP-glucose (UDPG) to glucose 6-phosphate to produce trehalose-6-phosphate. Herein we describe the characterization of a trehalose-6-phosphate synthase from the thermoacidophilic archaeon Thermoplasma acidophilum. The dimeric enzyme could utilize UDPG, ADP-Glucose (ADPG) and GDP-Glucose (GDPG) as glycosyl donors and various phosphorylated monosaccharides as glycosyl acceptors. The optimal temperature and pH were found to be 60 °C and pH 6, and the enzyme exhibited notable pH and thermal stability. The enzymatic activity could be stimulated by divalent metal ions and polyanions heparin and chondroitin sulfate. Moreover, the protein was considerably resistant to additives ethanol, EDTA, urea, DTT, SDS, ß-mercaptoethanol, methanol, isopropanol and n-butanol. Molecular modeling and mutagenesis analysis revealed that the N-loop region was important for the catalytic efficiency of the enzyme, indicating different roles of N-loop sequences in different trehalose-6-phosphate synthases.
[Mh] Termos MeSH primário: Proteínas Arqueais/química
Glucosiltransferases/química
Thermoplasma/enzimologia
[Mh] Termos MeSH secundário: Adenosina Difosfato Glucose/química
Sequência de Aminoácidos
Substituição de Aminoácidos
Proteínas Arqueais/genética
Domínio Catalítico
Estabilidade Enzimática
Glucosiltransferases/genética
Glicosilação
Açúcares de Guanosina Difosfato/química
Concentração de Íons de Hidrogênio
Magnésio/química
Modelos Moleculares
Dados de Sequência Molecular
Mutagênese Sítio-Dirigida
Desnaturação Proteica
Estrutura Quaternária de Proteína
Especificidade por Substrato
Uridina Difosfato Glucose/química
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Archaeal Proteins); 0 (Guanosine Diphosphate Sugars); 2140-58-1 (Adenosine Diphosphate Glucose); 5750-57-2 (guanosine diphosphate glucose); EC 2.4.1.- (Glucosyltransferases); EC 2.4.1.15 (trehalose-6-phosphate synthase); I38ZP9992A (Magnesium); J41CSQ7QDS (Zinc); V50K1D7P4Y (Uridine Diphosphate Glucose)
[Em] Mês de entrada:1412
[Cu] Atualização por classe:140421
[Lr] Data última revisão:
140421
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140211
[St] Status:MEDLINE


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[PMID]:24231376
[Au] Autor:Kawano Y; Sekine M; Ihara M
[Ad] Endereço:Faculty of Agriculture, Shinshu University, 8304 Minamiminowa, Nagano 399-4511, Japan; Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
[Ti] Título:Identification and characterization of UDP-glucose pyrophosphorylase in cyanobacteria Anabaena sp. PCC 7120.
[So] Source:J Biosci Bioeng;117(5):531-8, 2014 May.
[Is] ISSN:1347-4421
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Exopolysaccharides produced by photosynthetic cyanobacteria have received considerable attention in recent years for their potential applications in the production of renewable biofuels. Particularly, cyanobacterial cellulose is one of the most promising products because it is extracellularly secreted as a non-crystalline form, which can be easily harvested from the media and converted into glucose units. In cyanobacteria, the production of UDP-glucose, the cellulose precursor, is a key step in the cellulose synthesis pathway. UDP-glucose is synthesized from UTP and glucose-1-phosphate (Glc-1P) by UDP-glucose pyrophosphorylase (UGPase), but this pathway in cyanobacteria has not been well characterized. Therefore, to elucidate the overall cellulose biosynthesis pathway in cyanobacteria, we studied the putative UGPase All3274 and seven other putative NDP-sugar pyrophosphorylases (NSPases), All4645, Alr2825, Alr4491, Alr0188, Alr3400, Alr2361, and Alr3921 of Anabaena sp. PCC 7120. Assays using the purified recombinant proteins revealed that All3274 exhibited UGPase activity, All4645, Alr2825, Alr4491, Alr0188, and Alr3921 exhibited pyrophosphorylase activities on ADP-glucose, CDP-glucose, dTDP-glucose, GDP-mannose, and UDP-N-acetylglucosamine, respectively. Further characterization of All3274 revealed that the kcat for UDP-glucose formation was one or two orders lower than those of other known UGPases. The activity and dimerization tendency of All3274 increased at higher enzyme concentrations, implying catalytic activation by dimerization. However, most interestingly, All3274 dimerization was inhibited by UTP and Glc-1P, but not by UDP-glucose. This study presents the first in vitro characterization of a cyanobacterial UGPase, and provides insights into biotechnological attempts to utilize the photosynthetic production of cellulose from cyanobacteria.
[Mh] Termos MeSH primário: Anabaena/enzimologia
UTP-Glucose-1-Fosfato Uridililtransferase/isolamento & purificação
UTP-Glucose-1-Fosfato Uridililtransferase/metabolismo
[Mh] Termos MeSH secundário: Adenosina Difosfato Glucose/metabolismo
Sequência de Aminoácidos
Celulose/metabolismo
Clonagem Molecular
Reagentes para Ligações Cruzadas
Glucose/análogos & derivados
Glucose/metabolismo
Cinética
Dados de Sequência Molecular
Açúcares de Nucleosídeo Difosfato/metabolismo
Proteínas Recombinantes/biossíntese
Proteínas Recombinantes/química
Proteínas Recombinantes/isolamento & purificação
Proteínas Recombinantes/metabolismo
Análise de Sequência de DNA
Especificidade por Substrato
Nucleotídeos de Timina/metabolismo
UTP-Glucose-1-Fosfato Uridililtransferase/biossíntese
UTP-Glucose-1-Fosfato Uridililtransferase/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cross-Linking Reagents); 0 (Nucleoside Diphosphate Sugars); 0 (Recombinant Proteins); 0 (Thymine Nucleotides); 0 (cytidine diphosphate-glucose); 0 (deoxythymidine diphosphate-glucose); 2140-58-1 (Adenosine Diphosphate Glucose); 9004-34-6 (Cellulose); EC 2.7.7.9 (UTP-Glucose-1-Phosphate Uridylyltransferase); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1408
[Cu] Atualização por classe:140331
[Lr] Data última revisão:
140331
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:131116
[St] Status:MEDLINE


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[PMID]:24092883
[Au] Autor:Kaneko K; Inomata T; Masui T; Koshu T; Umezawa Y; Itoh K; Pozueta-Romero J; Mitsui T
[Ad] Endereço:Department of Applied Biological Chemistry, Niigata University, 2-8050 Ikarashi, Niigata, 950-2181 Japan.
[Ti] Título:Nucleotide pyrophosphatase/phosphodiesterase 1 exerts a negative effect on starch accumulation and growth in rice seedlings under high temperature and CO2 concentration conditions.
[So] Source:Plant Cell Physiol;55(2):320-32, 2014 Feb.
[Is] ISSN:1471-9053
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Nucleotide pyrophosphatase/phosphodiesterase (NPP) is a widely distributed enzymatic activity occurring in both plants and mammals that catalyzes the hydrolytic breakdown of the pyrophosphate and phosphodiester bonds of a number of nucleotides. Unlike mammalian NPPs, the physiological function of plant NPPs remains largely unknown. Using a complete rice NPP1-encoding cDNA as a probe, in this work we have screened a rice shoot cDNA library and obtained complete cDNAs corresponding to six NPP genes (NPP1-NPP6). As a first step to clarify the role of NPPs, recombinant NPP1, NPP2 and NPP6 were purified from transgenic rice cells constitutively expressing NPP1, NPP2 and NPP6, respectively, and their enzymatic properties were characterized. NPP1 and NPP6 exhibited hydrolytic activities toward ATP, UDP-glucose and the starch precursor molecule, ADP-glucose, whereas NPP2 did not recognize nucleotide sugars as substrates, but hydrolyzed UDP, ADP and adenosine 5'-phosphosulfate. To gain insight into the physiological function of rice NPP1, an npp1 knockout mutant was characterized. The ADP-glucose hydrolytic activities in shoots of npp1 rice seedlings were 8% of those of the wild type (WT), thus indicating that NPP1 is a major determinant of ADP-glucose hydrolytic activity in rice shoots. Importantly, when seedlings were cultured at 160 Pa CO2 under a 28°C/23°C (12 h light/12 h dark) regime, npp1 shoots and roots were larger than those of wild-type (WT) seedlings. Furthermore, the starch content in the npp1 shoots was higher than that of WT shoots. Growth and starch accumulation were also enhanced under an atmospheric CO2 concentration (40 Pa) when plants were cultured under a 33°C/28°C regime. The overall data strongly indicate that NPP1 exerts a negative effect on plant growth and starch accumulation in shoots, especially under high CO2 concentration and high temperature conditions.
[Mh] Termos MeSH primário: Dióxido de Carbono/metabolismo
Oryza/enzimologia
Diester Fosfórico Hidrolases/metabolismo
Pirofosfatases/metabolismo
Amido/metabolismo
[Mh] Termos MeSH secundário: Adenosina Difosfato Glucose/metabolismo
Sequência de Bases
Dióxido de Carbono/farmacologia
Células Cultivadas
DNA Complementar/genética
Expressão Gênica
Regulação da Expressão Gênica de Plantas
Técnicas de Inativação de Genes
Dados de Sequência Molecular
Mutação
Oryza/efeitos dos fármacos
Oryza/genética
Oryza/fisiologia
Diester Fosfórico Hidrolases/genética
Folhas de Planta/efeitos dos fármacos
Folhas de Planta/enzimologia
Folhas de Planta/genética
Folhas de Planta/fisiologia
Proteínas de Plantas/genética
Proteínas de Plantas/metabolismo
Raízes de Plantas/efeitos dos fármacos
Raízes de Plantas/enzimologia
Raízes de Plantas/genética
Raízes de Plantas/fisiologia
Brotos de Planta/efeitos dos fármacos
Brotos de Planta/enzimologia
Brotos de Planta/genética
Brotos de Planta/fisiologia
Pirofosfatases/genética
Plântulas/efeitos dos fármacos
Plântulas/enzimologia
Plântulas/genética
Plântulas/fisiologia
Análise de Sequência de DNA
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (Plant Proteins); 142M471B3J (Carbon Dioxide); 2140-58-1 (Adenosine Diphosphate Glucose); 9005-25-8 (Starch); EC 3.1.4.- (Phosphoric Diester Hydrolases); EC 3.6.1.- (Pyrophosphatases); EC 3.6.1.9 (nucleotide pyrophosphatase)
[Em] Mês de entrada:1410
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:131005
[St] Status:MEDLINE
[do] DOI:10.1093/pcp/pct139


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[PMID]:23952675
[Au] Autor:Crumpton-Taylor M; Pike M; Lu KJ; Hylton CM; Feil R; Eicke S; Lunn JE; Zeeman SC; Smith AM
[Ad] Endereço:John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK.
[Ti] Título:Starch synthase 4 is essential for coordination of starch granule formation with chloroplast division during Arabidopsis leaf expansion.
[So] Source:New Phytol;200(4):1064-75, 2013 Dec.
[Is] ISSN:1469-8137
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Arabidopsis thaliana mutants lacking the SS4 isoform of starch synthase have strongly reduced numbers of starch granules per chloroplast, suggesting that SS4 is necessary for the normal generation of starch granules. To establish whether it plays a direct role in this process, we investigated the circumstances in which granules are formed in ss4 mutants. Starch granule numbers and distribution and the accumulation of starch synthase substrates and products were investigated during ss4 leaf development, and in ss4 mutants carrying mutations or transgenes that affect starch turnover or chloroplast volume. We found that immature ss4 leaves have no starch granules, but accumulate high concentrations of the starch synthase substrate ADPglucose. Granule numbers are partially restored by elevating the capacity for glucan synthesis (via expression of bacterial glycogen synthase) or by increasing the volumes of individual chloroplasts (via introduction of arc mutations). However, these granules are abnormal in distribution, size and shape. SS4 is an essential component of a mechanism that coordinates granule formation with chloroplast division during leaf expansion and determines the abundance and the flattened, discoid shape of leaf starch granules.
[Mh] Termos MeSH primário: Arabidopsis/enzimologia
Arabidopsis/crescimento & desenvolvimento
Cloroplastos/metabolismo
Folhas de Planta/enzimologia
Folhas de Planta/crescimento & desenvolvimento
Sintase do Amido/metabolismo
Amido/biossíntese
[Mh] Termos MeSH secundário: Adenosina Difosfato Glucose/metabolismo
Agrobacterium/enzimologia
Glucanos/metabolismo
Glicogênio Sintase/metabolismo
Heterozigoto
Isoenzimas/metabolismo
Metaboloma
Mutação/genética
Tamanho das Organelas
Interferência de RNA
Solubilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Glucans); 0 (Isoenzymes); 2140-58-1 (Adenosine Diphosphate Glucose); 9005-25-8 (Starch); EC 2.4.1.11 (Glycogen Synthase); EC 2.4.1.21 (Starch Synthase); EC 2.4.1.21 (starch synthase IV, Arabidopsis)
[Em] Mês de entrada:1411
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130820
[St] Status:MEDLINE
[do] DOI:10.1111/nph.12455


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[PMID]:23872660
[Au] Autor:Ragel P; Streb S; Feil R; Sahrawy M; Annunziata MG; Lunn JE; Zeeman S; Mérida Á
[Ad] Endereço:Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas-University of Sevilla, 41092 Seville, Spain.
[Ti] Título:Loss of starch granule initiation has a deleterious effect on the growth of arabidopsis plants due to an accumulation of ADP-glucose.
[So] Source:Plant Physiol;163(1):75-85, 2013 Sep.
[Is] ISSN:1532-2548
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:STARCH SYNTHASE4 (SS4) is required for proper starch granule initiation in Arabidopsis (Arabidopsis thaliana), although SS3 can partially replace its function. Unlike other starch-deficient mutants, ss4 and ss3/ss4 mutants grow poorly even under long-day conditions. They have less chlorophyll and carotenoids than the wild type and lower maximal rates of photosynthesis. There is evidence of photooxidative damage of the photosynthetic apparatus in the mutants from chlorophyll a fluorescence parameters and their high levels of malondialdehyde. Metabolite profiling revealed that ss3/ss4 accumulates over 170 times more ADP-glucose (Glc) than wild-type plants. Restricting ADP-Glc synthesis, by introducing mutations in the plastidial phosphoglucomutase (pgm1) or the small subunit of ADP-Glc pyrophosphorylase (aps1), largely restored photosynthetic capacity and growth in pgm1/ss3/ss4 and aps1/ss3/ss4 triple mutants. It is proposed that the accumulation of ADP-Glc in the ss3/ss4 mutant sequesters a large part of the plastidial pools of adenine nucleotides, which limits photophosphorylation, leading to photooxidative stress, causing the chlorotic and stunted growth phenotypes of the plants.
[Mh] Termos MeSH primário: Adenosina Difosfato Glucose/metabolismo
Arabidopsis/crescimento & desenvolvimento
Amido/metabolismo
[Mh] Termos MeSH secundário: Arabidopsis/metabolismo
Proteínas de Arabidopsis/genética
Mutação
Estresse Oxidativo
Fosforilação
Fotossíntese
Sintase do Amido/genética
Sintase do Amido/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Arabidopsis Proteins); 2140-58-1 (Adenosine Diphosphate Glucose); 9005-25-8 (Starch); EC 2.4.1.21 (Starch Synthase)
[Em] Mês de entrada:1404
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130723
[St] Status:MEDLINE
[do] DOI:10.1104/pp.113.223420



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