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Wilson WA, Roach PJ, Montero M, Baroja-Fernández E, Muñoz FJ, Eydallin G, Viale AM, Pozueta-Romero J. Regulation of glycogen metabolism in yeast and bacteria. FEMS Microbiol Rev 2011; 34:952-85. [PMID: 20412306 DOI: 10.1111/j.1574-6976.2010.00220.x] [Citation(s) in RCA: 253] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Microorganisms have the capacity to utilize a variety of nutrients and adapt to continuously changing environmental conditions. Many microorganisms, including yeast and bacteria, accumulate carbon and energy reserves to cope with the starvation conditions temporarily present in the environment. Glycogen biosynthesis is a main strategy for such metabolic storage, and a variety of sensing and signaling mechanisms have evolved in evolutionarily distant species to ensure the production of this homopolysaccharide. At the most fundamental level, the processes of glycogen synthesis and degradation in yeast and bacteria share certain broad similarities. However, the regulation of these processes is sometimes quite distinct, indicating that they have evolved separately to respond optimally to the habitat conditions of each species. This review aims to highlight the mechanisms, both at the transcriptional and at the post-transcriptional level, that regulate glycogen metabolism in yeast and bacteria, focusing on selected areas where the greatest increase in knowledge has occurred during the last few years. In the yeast system, we focus particularly on the various signaling pathways that control the activity of the enzymes of glycogen storage. We also discuss our recent understanding of the important role played by the vacuole in glycogen metabolism. In the case of bacterial glycogen, special emphasis is placed on aspects related to the genetic regulation of glycogen metabolism and its connection with other biological processes.
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Affiliation(s)
- Wayne A Wilson
- Biochemistry and Nutrition Department, Des Moines University, Des Moines, IA, USA
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Wilson WA, Wang Z, Roach PJ. Regulation of yeast glycogen phosphorylase by the cyclin-dependent protein kinase Pho85p. Biochem Biophys Res Commun 2005; 329:161-7. [PMID: 15721288 DOI: 10.1016/j.bbrc.2005.01.106] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2005] [Indexed: 11/16/2022]
Abstract
Yeast accumulate glycogen in response to nutrient limitation. The key enzymes of glycogen synthesis and degradation, glycogen synthase, and phosphorylase, are regulated by reversible phosphorylation. Phosphorylation inactivates glycogen synthase but activates phosphorylase. The kinases and phosphatases that control glycogen synthase are well characterized whilst the enzymes modifying phosphorylase are poorly defined. Here, we show that the cyclin-dependent protein kinase, Pho85p, which we have previously found to regulate glycogen synthase also controls the phosphorylation state of phosphorylase.
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Affiliation(s)
- Wayne A Wilson
- Department of Biochemistry and Molecular Biology, Center for Diabetes Research, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Nigavekar SS, Tan YSH, Cannon JF. Glc8 is a glucose-repressible activator of Glc7 protein phosphatase-1. Arch Biochem Biophys 2002; 404:71-9. [PMID: 12127071 DOI: 10.1016/s0003-9861(02)00231-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Regulation of Glc7 type 1 protein phosphatase stability and activity was studied in budding yeast. We found that the Glc7 protein has a half-life of over 180min, which is sufficient for several generations. Glc7 protein stability was constant during the cell cycle and in batch culture growth. Furthermore, deletion of regulatory subunit Gac1, Reg1, Reg2, Sds22, or Glc8 had no influence on Glc7 protein half-life. The activity of Glc7 assayed as okadaic acid-resistant phosphorylase phosphatase activity was constant during the cell cycle. Deletion of the aforementioned regulatory subunits revealed that only Glc8 deletion had a significant effect in reducing Glc7 activity. Glc7 activity was induced during stationary phase in a Glc8-dependent manner. In addition, extracellular glucose repressed the induction of Glc7 activity. These results are consistent with glucose repression of Glc8 expression and favor the role of Glc8 as a major Glc7 activator.
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Affiliation(s)
- Shraddha S Nigavekar
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia 65212, USA
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Wilson WA, Wang Z, Roach PJ. Systematic identification of the genes affecting glycogen storage in the yeast Saccharomyces cerevisiae: implication of the vacuole as a determinant of glycogen level. Mol Cell Proteomics 2002; 1:232-42. [PMID: 12096123 DOI: 10.1074/mcp.m100024-mcp200] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
At the onset of nutrient limitation, the yeast Saccharomyces cerevisiae synthesizes glycogen to serve as a carbon and energy reserve. We undertook a systematic survey for the genes that affect glycogen accumulation by taking advantage of the strain deletion set generated by the Saccharomyces Genome Deletion Project. The strain collection analyzed contained some 4600 diploid homozygous null deletants, representing approximately 88% of all viable haploid disruptants. We identified 324 strains with low and 242 with elevated glycogen stores, accounting for 12.4% of the genes analyzed. The screen was validated by the identification of many of the genes known already to influence glycogen accumulation. Many of the mutants could be placed into coherent families. For example, 195 or 60% of the hypoaccumulators carry mutations linked to respiratory function, a class of mutants well known to be defective in glycogen storage. The second largest group consists of approximately 60 genes involved in vesicular trafficking and vacuolar function, including genes encoding 13 of 17 proteins involved in the structure or assembly of the vacuolar ATPase. These data are consistent with our recent findings that the process of autophagy has a significant impact on glycogen storage (Wang, Z., Wilson, W. A., Fujino, M. A., and Roach, P. J. (2001) Antagonistic controls of autophagy and glycogen accumulation by Snf1p, the yeast homolog of AMP-activated protein kinase, and the cyclin-dependent kinase Pho85p. Mol. Cell. Biol. 21, 5742-5752). Autophagy delivers glycogen to the vacuole, and we propose that the impaired vacuolar function associated with ATPase mutants (vma10 or vma22) results in reduced degradation and subsequent hyperaccumulation of glycogen.
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Affiliation(s)
- Wayne A Wilson
- Department of Biochemistry and Molecular Biology and Center for Diabetes Research, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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Abstract
Glycogen and trehalose are the two glucose stores of yeast cells. The large variations in the cell content of these two compounds in response to different environmental changes indicate that their metabolism is controlled by complex regulatory systems. In this review we present information on the regulation of the activity of the enzymes implicated in the pathways of synthesis and degradation of glycogen and trehalose as well as on the transcriptional control of the genes encoding them. cAMP and the protein kinases Snf1 and Pho85 appear as major actors in this regulation. From a metabolic point of view, glucose-6-phosphate seems the major effector in the net synthesis of glycogen and trehalose. We discuss also the implication of the recently elucidated TOR-dependent nutrient signalling pathway in the control of the yeast glucose stores and its integration in growth and cell division. The unexpected roles of glycogen and trehalose found in the control of glycolytic flux, stress responses and energy stores for the budding process, demonstrate that their presence confers survival and reproductive advantages to the cell. The findings discussed provide for the first time a teleonomic value for the presence of two different glucose stores in the yeast cell.
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Affiliation(s)
- J François
- Centre de Bioingenierie Gilbert Durand, UMR-CNRS 5504, UMR-INRA 792, Département de Génie Biochimique et Alimentaire, Institut National des Sciences Appliquées, 135 Avenue de Rangeuil, 31077 Toulouse Cedex 04, France.
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Queiroz-Claret C, Jolivet P, Chardot T, Bergeron E, Meunier JC. Time-co-ordinated control of glycogen synthase, protein phosphatase 2A and protein kinase CK2 during culture growth in Yarrowia lipolytica in relation to glycogen metabolism. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 2000; 323:257-66. [PMID: 10782329 DOI: 10.1016/s0764-4469(00)00127-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
In the growth course of the lipolytic yeast Yarrowia lipolytica, the activities of protein phosphatase 2A (PP2A) and glycogen synthase (GS) rise during the exponential phase and concomitantly glycogen storage occurs in the cells. There is also an increase in the independence ratio (RI) indicating a shift from an inactive phosphorylated GS form to an active dephosphorylated GS form. During the early stationary phase, an increase in protein kinase CK2 (CK2) activity, a reversion of RI variation and a glycogen content decrease are observed. GS activity proved to be a good indicator of early culture growth phase. Experiments carried out with enzymes purified from Y. lipolytica show strong RI variations upon the action of CK2 and PP2Ac, and 32P incorporation into GS protein through phosphorylation by CK2. GS activity would be controlled by the sequential action of PP2A and CK2.
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Affiliation(s)
- C Queiroz-Claret
- Laboratoire de chimie biologique, Inra, Ina-PG, Centre de biotechnologie agro-industrielle, Thiverval-Grignon, France
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Jolivet P, Queiroz-Claret C, Bergeron E, Meunier JC. Purification and characterization of a type 2A protein phosphatase from Yarrowia lipolytica grown on a phosphate-deficient medium. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 1997; 320:441-9. [PMID: 9247023 DOI: 10.1016/s0764-4469(97)81971-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Intracellular protein phosphatase activity has been identified in the yeast Yarrowia lipolytica. This activity was maximal early in its exponential growth phase, and it was enhanced by Pi-deficiency of the culture medium. On a Pi-deficient medium, the major protein phosphatase was purified. This enzyme was dissociated with 80% ethanol treatment, its activity was slightly increased (30%) with heparine and largely enhanced (1.5 to 3-fold) with polycations. This enzyme could be classified as a type 2A protein phosphatase. It is composed of a catalytic subunit and other subunits. Its optimum pH value is 7.2, the apparent Km for casein is 37 microM and the apparent velocity 3.6 pmol hydrolyzed32 Pi min-1 pmol-1 enzyme.
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Affiliation(s)
- P Jolivet
- Laboratoire de chimie biologique, Inra, Ina-PG, Centre de biotechnologies agro-industrielles, Thiverval-Grignon, France
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Abstract
Since the isolation of the first yeast protein phosphatase genes in 1989, much progress has been made in understanding this important group of proteins. Yeast contain genes encoding all the major types of protein phosphatase found in higher eukaryotes and the ability to use genetic approaches will complement the wealth of biochemical information available from other systems. This review will summarize recent progress in understanding the structure, function and regulation of the PPP family of protein serine-threonine phosphatases, concentrating on the budding yeast Saccharomyces cerevisiae.
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Affiliation(s)
- M J Stark
- Department of Biochemistry, University of Dundee, UK
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Abstract
Since the isolation of the first yeast protein phosphatase genes in 1989, much progress has been made in understanding this important group of proteins. Yeast contain genes encoding all the major types of protein phosphatase found in higher eukaryotes and the ability to use genetic approaches will complement the wealth of biochemical information available from other systems. This review will summarize recent progress in understanding the structure, function and regulation of the PPP family of protein serine-threonine phosphatases, concentrating on the budding yeast Saccharomyces cerevisiae.
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Affiliation(s)
- M J Stark
- Department of Biochemistry, University of Dundee, UK
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Farkas I, Bakó E, Murányi A, Zeke T, Sipiczki M, Gergely P. Quantitation of protein phosphatase 1 and 2A in extracts of the budding yeast and fission yeast. Int J Biochem Cell Biol 1995; 27:767-73. [PMID: 7584610 DOI: 10.1016/1357-2725(95)00052-q] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Serine/threonine protein phosphatases are also involved in the control of cell division. The aim of the present study was to compare the activity of protein phosphatase 1 (PP1) and 2A (PP2A) in cell extracts of the budding and fission yeast, made at different phases of growth. The activities of PP1 and PP2A toward phosphorylase were similar in extracts of S. cerevisiae. In S. pombe extracts, PP1 was responsible for more than 80% of the phosphorylase phosphatase activity. Ammonium sulfate-ethanol treatment increased the specific activity of the phosphatases and the percentage of PP2A in S. cerevisiae extracts. No increase in the proportion of PP2A was observed upon the same treatment of S. pombe extracts. The above results were confirmed by fractionation of PP1 and PP2A activities on a heparin-Sepharose column. The proportion of PP1 and PP2A activities did not change significantly during exponential cell growth but cells from stationary phase exhibited lower phosphatase activities. These results may indicate a lower level of expression of the PP2A genes in S. pombe and/or differences in the structure of the holoenzymes or their regulators in the two genera.
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Affiliation(s)
- I Farkas
- Department of Medical Chemistry, University School of Medicine, Debrecen, Hungary
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Clotet J, Posas F, Hu GZ, Ronne H, Arino J. Role of Protein Phosphatase 2A in the Control of Glycogen Metabolism in Yeast. ACTA ACUST UNITED AC 1995. [DOI: 10.1111/j.1432-1033.1995.0207l.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Guy GR, Philp R, Tan YH. Activation of Protein Kinases and the Inactivation of Protein Phosphatase 2A in Tumour Necrosis Factor and Interleukin-1 Signal-Transduction Pathways. ACTA ACUST UNITED AC 1995. [DOI: 10.1111/j.1432-1033.1995.tb20491.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Stark MJ, Black S, Sneddon AA, Andrews PD. Genetic analyses of yeast protein serine/threonine phosphatases. FEMS Microbiol Lett 1994; 117:121-30. [PMID: 8181714 DOI: 10.1111/j.1574-6968.1994.tb06753.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Protein phosphorylation is an important regulatory phenomenon in yeasts just as in other eukaryotic cells and controls a wide variety of cellular processes. The importance of protein phosphatases as well as protein kinases as key elements in such control is becoming increasingly clear. Over the past four years since the first yeast protein phosphatase gene was isolated, many more such genes have been described and the number of genes encoding protein phosphatase catalytic subunits in Saccharomyces cerevisiae has comfortably entered double figures. Given the genetic approaches available, yeasts offer powerful systems for addressing the cellular roles of these enzymes. This review summarises the results of genetic studies aimed at determining the functions of protein serine/threonine phosphatases in yeast.
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Affiliation(s)
- M J Stark
- Department of Biochemistry, The University, Dundee, UK
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14
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Guy GR, Philip R, Tan YH. Analysis of cellular phosphoproteins by two-dimensional gel electrophoresis: applications for cell signaling in normal and cancer cells. Electrophoresis 1994; 15:417-40. [PMID: 8055870 DOI: 10.1002/elps.1150150160] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Two-dimensional (2-D) gel electrophoresis has been used to map proteins from various cell types in an effort to eventually link such maps to the sequencing of the entire human genome. While this analysis indicates the cellular disposition and expression of proteins, another application of 2-D gels, the analysis of phosphoproteins, can provide much information as to the assembly and "wiring" of the signal transduction circuits within cells which appear to be enervated by phosphate exchange. The preparation and separation of 32P-labeled proteins is described, as well as various analytical methods, including: the variety of gel systems available for specialist types of analyses, comparing 33P- and 32P-labeling of proteins, imaging techniques, phosphoamino analysis, phosphopeptide separation, identifying the amino acid groups that are phosphorylated, and the identification of phosphoproteins on 2-D gels by immunoprecipitation, corunning of purified proteins, comparative mapping and microsequencing, and by Western blotting. Examples (in brackets) are given of applications in which 2-D phosphogels can be applied, which offer advantages over other techniques. These include: (i) identifying in vivo substrates for kinases (protein kinase C activated by phorbol myristate acetate), (ii) investigating cytokine signaling pathways (tumor necrosis factor and interleukin-1), (iii) investigating the effects of drugs on signaling pathways (okadaic acid, menadione and cyclooxygenase inhibitors), (iv) characterization of specific phosphoproteins (heat-shock protein Hsp27 and stathmin), (v) comparing normal and transformed cells (MRC-5 human lung fibroblasts and their SV-40-transformed counterparts, MRC-5 SV1 cells), (vi) purifying phosphoproteins, (vii) investigating the relationship of protein phosphorylation to stages in the cell cycle (stathmin), (viii) investigating protein/protein interactions, (ix) mapping in vitro kinase substrates (protein kinase C, protein kinase A, and mitogen activated protein kinase activated protein kinase 2), and (x) locating and identifying cellular phosphatases (Hsp27 phosphatase). It is possible that the mapping of phosphoproteins can be linked to other 2-D gel databases and that information derived from these can be used in the future to better understand the signaling mechanisms of normal and cancerous cells.
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Affiliation(s)
- G R Guy
- Signal Transduction Laboratory, National University of Singapore
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15
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Overexpression of yeast PAM1 gene permits survival without protein phosphatase 2A and induces a filamentous phenotype. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)41880-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Dautzenberg FM, Müller D, Richter D. Dephosphorylation of phosphorylated atrial natriuretic peptide by protein phosphatase 2A. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 211:485-90. [PMID: 8382153 DOI: 10.1111/j.1432-1033.1993.tb17574.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A phosphatase which exhibits strong activity toward phosphorylated atrial natriuretic peptide (ANP) was identified in the soluble fraction of rat brain homogenate. This ANP phosphatase has a neutral pH optimum, does not require divalent cations for activity, is inhibited by low concentrations of okadaic acid (50% inhibition at 1 nM) and preferentially dephosphorylates the alpha subunit of phosphorylase kinase. These properties are characteristic of serine/threonine protein phosphatase type 2A (PP2A). The apparent molecular mass of the ANP phosphatase (160 kDa), as estimated by gel filtration, is similar to that of the native heterotrimeric form of PP2A. In addition, phosphorylated ANP is an excellent substrate for the purified catalytic subunit of PP2A (Km = 42 microM, Vmax = 10.3 mumol x min-1 x mg-1). In contrast, protein phosphatase 2B (PP2B) has only very low ANP phosphatase activity (Km = 2.5 microM, Vmax = 0.008 mumol x min-1 x mg-1), and the catalytic subunit of protein phosphatase type 1 (PP1) as well as purified protein phosphatase type 2C (PP2C) are essentially inactive on ANP. These findings are consistent with the observation that PP2A-like activity accounts for virtually all ANP dephosphorylation in brain homogenate. While the phosphorylation of ANP in vitro by cAMP-dependent protein kinase is well documented, this is a first report on a phosphatase that efficiently can reverse this modification.
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Affiliation(s)
- F M Dautzenberg
- Institut für Zellbiochemie und klinische Neurobiologie, Universitätskrankenhaus Eppendorf, Universität Hamburg, Federal Republic of Germany
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17
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Posas F, Clotet J, Muns M, Corominas J, Casamayor A, Ariño J. The gene PPG encodes a novel yeast protein phosphatase involved in glycogen accumulation. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)54082-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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18
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Han YF, Wang W, Schlender KK, Ganjeizadeh M, Dokas LA. Protein phosphatases 1 and 2A dephosphorylate B-50 in presynaptic plasma membranes from rat brain. J Neurochem 1992; 59:364-74. [PMID: 1319470 DOI: 10.1111/j.1471-4159.1992.tb08913.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The protein B-50 is dephosphorylated in rat cortical synaptic plasma membranes (SPM) by protein phosphatase type 1 and 2A (PP-1 and PP-2A)-like activities. The present studies further demonstrate that B-50 is dephosphorylated not only by a spontaneously active PP-1-like enzyme, but also by a latent form after pretreatment of SPM with 0.2 mM cobalt/20 micrograms of trypsin/ml. The activity revealed by cobalt/trypsin was inhibited by inhibitor-2 and by high concentrations (microM) of okadaic acid, identifying it as a latent form of PP-1. In the presence of inhibitor-2 to block PP-1, histone H1 (16-64 micrograms/ml) and spermine (2 mM) increased B-50 dephosphorylation. This sensitivity to polycations and the reversal of their effects on B-50 dephosphorylation by 2 nM okadaic acid are indicative of PP-2A-like activity. PP-1- and PP-2A-like activities from SPM were further displayed by using exogenous phosphorylase alpha and histone H1 as substrates. Both PP-1 and PP-2A in rat SPM were immunologically identified with monospecific antibodies against the C-termini of catalytic subunits of rabbit skeletal muscle PP-1 and PP-2A. Okadaic acid-induced alteration of B-50 phosphorylation, consistent with inhibition of protein phosphatase activity, was demonstrated in rat cortical synaptosomes after immunoprecipitation with affinity-purified anti-B-50 immunoglobulin G. These results provide further evidence that SPM-bound PP-1 and PP-2A-like enzymes that share considerable similarities with their cytosolic counterparts may act as physiologically important phosphatases for B-50.
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Affiliation(s)
- Y F Han
- Departments of Biochemistry, Medical College of Ohio, Toledo 43699-0008
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Wang W, Lane RD, Schlender KK. Antibodies directed against synthetic peptides distinguish between the catalytic subunits of protein phosphatases 1 and 2A. Biochem Biophys Res Commun 1992; 185:657-62. [PMID: 1319144 DOI: 10.1016/0006-291x(92)91675-g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Two antipeptide antibodies (designated type 1 antibody and type 2A antibody) were raised against synthetic peptides, Cys-Thr-Pro-Pro-Arg-Asn-Ser-Ala-Lys-Ala-Lys-Lys and Cys-Val-Thr-Arg-Arg-Thr-Pro-Asp-Try-Phe-Leu, corresponding to the carboxyl termini of the catalytic subunits of protein phosphatase 1 and phosphatase 2A (Cys was added for specific coupling to carrier protein). These antipeptide antibodies were highly specific and were useful in discriminating between protein phosphatase 1 and phosphatase 2A in crude extracts or purified preparations. Type 2A antibody reacted with both native and denatured protein phosphatase 2A whereas under the same condition type 1 antibody reacted only with denatured protein phosphatase 1.
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Affiliation(s)
- W Wang
- Department of Pharmacology, Medical College of Ohio, Toledo 43699
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The yeast GLC7 gene required for glycogen accumulation encodes a type 1 protein phosphatase. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)54353-2] [Citation(s) in RCA: 97] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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