Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.2.1.13 (
glyceraldehyde-3-phosphate dehydrogenase
)
6,511
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In most flowering plants, the female gametophyte develops in an ovule deeply embedded in the ovary. Through double fertilization, the egg cell fuses with the sperm cell, resulting in a zygote, which develops into the embryo. In the present study, we analyzed egg cell lysates by polyacrylamide gel electrophoresis and subsequent mass spectrometry-based proteomics technology, and identified major protein components expressed in the egg cell. The identified proteins included three cytosolic enzymes of the glycolytic pathway,
glyceraldehyde-3-phosphate dehydrogenase
, 3-phosphoglycerate kinase and
triosephosphate isomerase
, two mitochondrial proteins, the ATP synthase beta-subunit and an adenine nucleotide transporter, and annexin p35. In addition, expression levels of these proteins in the egg cell were compared with those in the early embryo, the central cell and the suspension cell. Annexin p35 was highly expressed only in the egg cell, and
glyceraldehyde-3-phosphate dehydrogenase
, 3-phosphoglycerate kinase and the adenine nucleotide transporter were expressed at higher levels in egg cells than in central and cultured cells. These results indicate that annexin p35 in the egg cell and zygote is involved in the exocytosis of cell wall materials, which is induced by a fertilization-triggered increase in cytosolic Ca2+ levels, and that the egg cell is rich in an enzyme subset for the energy metabolism.
...
PMID:Identification of major proteins in maize egg cells. 1556 24
TPPP/p25, the first representative of a new protein family, identified as a brain-specific unfolded protein induces aberrant microtubule assemblies in vitro, suppresses mitosis in Drosophila embryo and is accumulated in inclusion bodies of human pathological brain tissues. In this paper, we present prediction and additional experimental data that validate TPPP/p25 to be a new member of the "intrinsically unstructured" protein family. The comparison of these characteristics with that of alpha-synuclein and tau, involved also in neurodegenerative diseases, suggested that although the primary sequences of these proteins are entirely different, there are similarities in their well-defined unstructured segments interrupted by "stabilization centres", phosphorylation and tubulin binding motives. SK-N-MC neuroblastoma cells were transfected with pEGFP-TPPP/p25 construct and a stable clone denoted K4 was selected and used to establish the effect of this unstructured protein on the energy state/metabolism of the cells. Our data by analyzing the mitochondrial membrane polarization by fluorescence microscopy revealed that the high-energy phosphate production in K4 clone is not damaged by the TPPP/p25 expression. Biochemical analysis with cell homogenates provided quantitative data that the ATP level increased 1.5-fold and the activities of hexokinase, glucosephosphate isomerase, phosphofructokinase,
triosephosphate isomerase
and
glyceraldehyde-3-phosphate dehydrogenase
were 1.2 to 2.0-fold higher in K4 as compared to the control. Our modelling using these data and rate equations of the individual enzymes suggests that the TPPP/p25 expression stimulates glucose metabolism. At pathological conditions TPPP/p25 is localized in inclusion bodies in multiple system atrophy, it tightly co-localizes with alpha-synuclein, partially with tubulin and not with vimentin. The previous and the present studies obtained with immunohistochemistry with pathological human brain tissues rendered it possible to classify among pathological inclusions on the basis of immunolabelling of TPPP/p25, and suggest this protein to be a potential linkage between Parkinson's and Alzheimer's diseases.
...
PMID:TPPP/p25: from unfolded protein to misfolding disease: prediction and experiments. 1556 25
The synthesis of ATP in the human parasite Entamoeba histolytica is carried out solely by the glycolytic pathway. Little kinetic and structural information is available for most of the pathway enzymes. We report here the gene cloning, overexpression and purification of hexokinase, hexose-6-phosphate isomerase, inorganic pyrophosphate-dependent phosphofructokinase, fructose-1,6 bisphosphate aldolase (ALDO),
triosephosphate isomerase
,
glyceraldehyde-3-phosphate dehydrogenase
(
GAPDH
), phosphoglycerate kinase, phosphoglycerate mutase (PGAM), enolase, and pyruvate phosphate dikinase (PPDK) enzymes from E. histolytica. Kinetic characterization of these 10 recombinant enzymes was made, establishing the kinetic constants at optimal and physiological pH values, analyzing the effect of activators and inhibitors, and investigating the storage stability and oligomeric state. Determination of the catalytic efficiencies at the pH optimum and at pH values that resemble those of the amoebal trophozoites was performed for each enzyme to identify possible controlling steps. This analysis suggested that PGAM, ALDO,
GAPDH
, and PPDK might be flux control steps, as they showed the lowest catalytic efficiencies. An in vitro reconstruction of the final stages of glycolysis was made to determine their flux control coefficients. Our results indicate that PGAM and PPDK exhibit high control coefficient values at physiological pH.
...
PMID:Glycolysis in Entamoeba histolytica. Biochemical characterization of recombinant glycolytic enzymes and flux control analysis. 1579 63
Enzymes of the gluconeogenic/glycolytic pathway (the Embden-Meyerhof-Parnas (EMP) pathway), the reductive tricarboxylic acid cycle, the reductive pentose phosphate cycle and the Entner-Doudoroff pathway are widely distributed and are often considered to be central to the origins of metabolism. In particular, several enzymes of the lower portion of the EMP pathway (the so-called trunk pathway), including
triosephosphate isomerase
(TPI; EC 5.3.1.1),
glyceraldehyde-3-phosphate dehydrogenase
(
GAPDH
; EC 1.2.1.12/13), phosphoglycerate kinase (PGK; EC 2.7.2.3) and enolase (EC 4.2.1.11), are extremely well conserved and universally distributed among the three domains of life. In this paper, the distribution of enzymes of gluconeogenesis/glycolysis in hyperthermophiles--microorganisms that many believe represent the least evolved organisms on the planet--is reviewed. In addition, the phylogenies of the trunk pathway enzymes (TPIs, GAPDHs, PGKs and enolases) are examined. The enzymes catalyzing each of the six-carbon transformations in the upper portion of the EMP pathway, with the possible exception of aldolase, are all derived from multiple gene sequence families. In contrast, single sequence families can account for the archaeal and hyperthermophilic bacterial enzyme activities of the lower portion of the EMP pathway. The universal distribution of the trunk pathway enzymes, in combination with their phylogenies, supports the notion that the EMP pathway evolved in the direction of gluconeogenesis, i.e., from the bottom up.
...
PMID:Distribution and phylogenies of enzymes of the Embden-Meyerhof-Parnas pathway from archaea and hyperthermophilic bacteria support a gluconeogenic origin of metabolism. 1580 66
Corynebacterium glutamicum gapA and gapB encode glyceraldehyde-3-phosphate dehydrogenases (GAPDHs) that differ in molecular weight and activity in the presence of ATP. Comparative genome analysis revealed that GapA, the product of gapA, represented the canonical
GAPDH
that is highly conserved across the three major life forms. GapB, with an additional 110-residue-long sequence upstream of its
GAPDH
-specific domain, was homologous only to select microbial putative GAPDHs. Upon gene disruption, the initial growth rates of the wild-type, DeltagapA and DeltagapB strains on glucose (0.77, 0.00 and 0.76 h(-1), respectively), lactate (0.20, 0.18 and 0.15 h(-1), respectively), pyruvate (0.39, 0.29 and 0.20 h(-1), respectively), and acetate (0.06, 0.06 and 0.04 h(-1), respectively), implied that GapA was indispensable for growth on glucose, that GapB, but not GapA, affected early growth on acetate, and that GapB had a greater influence on growth under gluconeogenic conditions than GapA. The disruption of either gapA or gapB showed no significant effect on the transcription of any of the other gap cluster genes although it led to reduced
triosephosphate isomerase
(
TPI
) activities. Glycolytic
GAPDH
activity at low in vitro ATP concentrations was solely attributed to the 35.9-kDa GapA. At higher ATP concentrations, the same activity was attributed to the 51.2-kDa GapB. Both enzymes, however, exhibited similar NADP-dependent
GAPDH
activities at the higher ATP concentrations. In effect therefore, the
GAPDH
-catalyzed reaction at low ATP concentrations was irreversible, with all the glycolytic activity strictly NAD-dependent and attributed to GapA. At higher ATP concentrations, the reaction was reversible, with glycolytic activity NAD- or NADP-dependent and attributed to GapB, while gluconeogenic activity was attributable to both GapA and GapB.
...
PMID:Corynebacterium glutamicum glyceraldehyde-3-phosphate dehydrogenase isoforms with opposite, ATP-dependent regulation. 1592
Epithelial cells of the thick ascending limb of Henle's loop (TALH cells) play a major role in the urinary concentrating mechanism. They are normally exposed to variable and often very high osmotic stress, which is particularly due to high sodium and chloride reabsorption and very low water permeability of the luminal membrane. It is already established that elevation of the activity of aldose reductase and hence an increase in intracellular sorbitol are indispensable for the osmotic adaptation and stability of the TALH cells. To identify new molecular factors potentially associated with the osmotic stress-resistant phenotype in kidney cells, TALH cells exhibiting low or high levels of resistance to osmotic stress were characterized using proteomic tools. Two-dimensional gel analysis showed a total number of 40 proteins that were differentially expressed in TALH cells under osmotic stress. Twenty-five proteins were overexpressed, whereas 15 proteins showed a down-regulation. Besides the sorbitol pathway enzyme aldose reductase, whose expression was 15 times increased, many other metabolic enzymes like glutathione S-transferase, malate dehydrogenase, lactate dehydrogenase, alpha enolase,
glyceraldehyde-3-phosphate dehydrogenase
, and
triose-phosphate isomerase
were up-regulated. Among the cytoskeleton proteins and cytoskeleton-associated proteins vimentin, cytokeratin, tropomyosin 4, and annexins I, II, and V were up-regulated, whereas tubulin and tropomyosins 1, 2, and 3 were down-regulated. The heat shock proteins alpha-crystallin chain B, HSP70, and HSP90 were found to be overexpressed. In contrast to the results in oxidative stress the endoplasmic reticulum stress proteins like glucose-regulated proteins (GRP78, GRP94, and GRP96), calreticulin, and protein-disulfide isomerase were down-regulated under hypertonic stress.
...
PMID:Proteomic analysis of cellular response to osmotic stress in thick ascending limb of Henle's loop (TALH) cells. 1597 15
The regulation of ATP-sensitive potassium (K(ATP)) channel activity is complex and a multitude of factors determine their open probability. Physiologically and pathophysiologically, the most important of these are intracellular nucleotides, with a long-recognized role for glycolytically derived ATP in regulating channel activity. To identify novel regulatory subunits of the K(ATP) channel complex, we performed a two-hybrid protein-protein interaction screen, using as bait the mouse Kir6.2 C terminus. Screening a rat heart cDNA library, we identified two potential interacting proteins to be the glycolytic enzymes,
glyceraldehyde-3-phosphate dehydrogenase
(
GAPDH
) and
triose-phosphate isomerase
. The veracity of interaction was verified by co-immunoprecipitation techniques in transfected mammalian cells. We additionally demonstrated that pyruvate kinase also interacts with Kir6.2 subunits. The physiological relevance of these interactions is illustrated by the demonstration that native Kir6.2 protein similarly interact with
GAPDH
and pyruvate kinase in rat heart membrane fractions and that Kir6.2 protein co-localize with these glycolytic enzymes in rat ventricular myocytes. The functional relevance of our findings is demonstrated by the ability of
GAPDH
or pyruvate kinase substrates to directly block the K(ATP) channel under patch clamp recording conditions. Taken together, our data provide direct evidence for the concept that key enzymes involved in glycolytic ATP production are part of a multisubunit K(ATP) channel protein complex. Our data are consistent with the concept that the activity of these enzymes (possibly by ATP formation in the immediate intracellular microenvironment of this macromolecular K(ATP) channel complex) causes channel closure.
...
PMID:The glycolytic enzymes, glyceraldehyde-3-phosphate dehydrogenase, triose-phosphate isomerase, and pyruvate kinase are components of the K(ATP) channel macromolecular complex and regulate its function. 1617 Feb
Multivariate data analysis has been combined with proteomics to enhance the recovery of information from 2-DE of cod muscle proteins during different storage conditions. Proteins were extracted according to 11 different storage conditions and samples were resolved by 2-DE. Data generated by 2-DE was subjected to principal component analysis (PCA) and discriminant partial least squares regression (DPLSR). Applying PCA to 2-DE data revealed the samples to form groups according to frozen storage time, whereas differences due to different storage temperatures or chilled storage in modified atmosphere packing did not lead to distinct changes in protein pattern. Applying DPLSR to the 2-DE data enabled the selection of protein spots critical for differentiation between 3 and 6 months frozen storage with 12 months frozen storage. Some of these protein spots have been identified by MS/MS, revealing myosin light chain 1, 2 and 3,
triose-phosphate isomerase
,
glyceraldehyde-3-phosphate dehydrogenase
, aldolase A and two alpha-actin fragments, and a nuclease diphosphate kinase B fragment to change in concentration, during frozen storage. Application of proteomics, multivariate data analysis and MS/MS to analyse protein changes in cod muscle proteins during storage has revealed new knowledge on the issue and enables a better understanding of biochemical processes occurring.
...
PMID:Changes in cod muscle proteins during frozen storage revealed by proteome analysis and multivariate data analysis. 1642 59
In the horticulturally important ornamental species Cyclamen persicum Mill., somatic embryogenesis is an efficient vegetative propagation method and the development of artificial seeds is an ultimate aim. This study aims at a systematic comparison of the proteomes of zygotic embryos, somatic embryos grown in liquid medium containing 30 or 60 g l(-1) sucrose, germinating embryos of both types and endosperm in order to obtain novel insights into seed and germination physiology. Using high resolution two-dimensional isoelectric focussing/sodium dodecylsulfate polyacrylamide gel electrophoresis (2D IEF/SDS PAGE), 74% of the proteins expressed in zygotic embryos were found in similar abundance in somatic embryos grown in 60 g l(-1) sucrose. Somatic embryos grown in 30 g l(-1) sucrose accumulated fewer protein species than those grown in 60 g l(-1). Selected proteins were identified following mass spectrometry (nano-LC-MS/MS). Four enzymes involved in glycolysis (UDP-glucose pyrophosphorylase, fructose bisphosphate aldolase,
triosephosphate isomerase
and
glyceraldehyde-3-phosphate dehydrogenase
GAPDH
) were specifically induced in somatic embryos. 11S globulin proteins identified by MS were present in high levels in somatic embryos, zygotic embryos and endosperm, whereas 7S globulins were detected mainly in endosperm and zygotic embryos. These are the first storage proteins identified in C. persicum. Xyloglucans are known to be another group of seed storage compounds in C. persicum. Interestingly, xyloglucan endotransglycosylases were found to be highly expressed in endosperm tissue. We discuss the physiological implications of these observations.
...
PMID:Proteomic analyses of somatic and zygotic embryos of Cyclamen persicum Mill. reveal new insights into seed and germination physiology. 1649 95
Density gradient separation of plastids from leaf and root tissue was carried out. The distribution in the gradients of the activity of the following enzymes was determined: nitrite reductase, glutamine synthetase, acetolactate synthetase, aspartate aminotransferase, catalase, cytochrome oxidase, and
triosephosphate isomerase
. The distribution of chlorophyll was followed in gradients from leaf tissue. The presence of plastids that have retained their stroma enzymes was denoted by a peak of
triosephosphate isomerase
activity. Coincidental with this peak were bands of nitrite reductase, acetolactate synthetase, glutamine synthetase, and aspartate aminotransferase activity. The results suggest that most, if not all, the nitrite reductase and acetolactate synthetase activity of the cell is in the plastids. The plastids were found to contain only part of the total glutamine synthetase, aspartate aminotransferase, and
triosephosphate dehydrogenase
activity in the cell. Some evidence was obtained for low levels of glutamate dehydrogenase activity in chloroplasts.
...
PMID:The location of nitrite reductase and other enzymes related to amino Acid biosynthesis in the plastids of root and leaves. 1665 26
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>