The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
David E. Levin - One of the best experts on this subject based on the ideXlab platform.
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Regulation of Cell Wall biogenesis in Saccharomyces cerevisiae: The Cell Wall integrity signaling pathway
Genetics, 2011Co-Authors: David E. LevinAbstract:The yeast Cell Wall is a strong, but elastic, structure that is essential not only for the maintenance of Cell shape and integrity, but also for progression through the Cell cycle. During growth and morphogenesis, and in response to environmental challenges, the Cell Wall is remodeled in a highly regulated and polarized manner, a process that is principally under the control of the Cell Wall integrity (CWI) signaling pathway. This pathway transmits Wall stress signals from the Cell surface to the Rho1 GTPase, which mobilizes a physiologic response through a variety of effectors. Activation of CWI signaling regulates the production of various carbohydrate polymers of the Cell Wall, as well as their polarized delivery to the site of Cell Wall remodeling. This review article centers on CWI signaling in Saccharomyces cerevisiae through the Cell cycle and in response to Cell Wall stress. The interface of this signaling pathway with other pathways that contribute to the maintenance of Cell Wall integrity is also discussed.
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Cell Wall integrity signaling in saccharomyces cerevisiae
Microbiology and Molecular Biology Reviews, 2005Co-Authors: David E. LevinAbstract:The yeast Cell Wall is a highly dynamic structure that is responsible for protecting the Cell from rapid changes in external osmotic potential. The Wall is also critical for Cell expansion during growth and morphogenesis. This review discusses recent advances in understanding the various signal transduction pathways that allow Cells to monitor the state of the Cell Wall and respond to environmental challenges to this structure. The Cell Wall integrity signaling pathway controlled by the small G-protein Rho1 is principally responsible for orchestrating changes to the Cell Wall periodically through the Cell cycle and in response to various forms of Cell Wall stress. This signaling pathway acts through direct control of Wall biosynthetic enzymes, transcriptional regulation of Cell Wall-related genes, and polarization of the actin cytoskeleton. However, additional signaling pathways interface both with the Cell Wall integrity signaling pathway and with the actin cytoskeleton to coordinate polarized secretion with Cell Wall expansion. These include Ca2+ signaling, phosphatidylinositide signaling at the plasma membrane, sphingoid base signaling through the Pkh1 and -2 protein kinases, Tor kinase signaling, and pathways controlled by the Rho3, Rho4, and Cdc42 G-proteins.
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Cell Wall Integrity Signaling in Saccharomyces cerevisiae
Microbiology and Molecular Biology Reviews, 2005Co-Authors: David E. LevinAbstract:Yeasts are uniCellular fungi which in the wild typically live on the surface of plants such as fruits and flowers. Existing in this setting, yeast Cells face the potential for exposure to rapid and extreme changes in environment, particularly with respect to osmotic potential. For instance, a yeast Cell living on the sugar-rich tissue of a grape can be exposed instantaneously to the hypo-osmotic shock of rainfall. To survive such rapid decreases in extraCellular osmolarity, the Cell must limit the influx of water so as to avoid bursting and to maintain an intraCellular water activity that is appropriate for biochemical reactions (121, 313). Yeasts and other fungi have solved this problem with strong and relatively rigid Cell Walls that limit swelling. The fungal Cell establishes a balance by which the force driving water across the osmotic gradient into the Cell is counteracted by turgor pressure against the plasma membrane and Cell Wall. The Cell Wall of the budding yeast Saccharomyces cerevisiae is also required to maintain Cell shape (50, 159), which is essential for the formation of a bud and hence Cell division. The Cell must remodel this rigid structure to accommodate Cell expansion during vegetative proliferation, mating pheromone-induced morphogenesis, and nutrient-driven filamentation. Turgor pressure is critical for Cell expansion, because it provides the force to overcome molecular cohesion within the Cell Wall (109). Because fungal Cells maintain an intraCellular osmolarity that exceeds that of the extraCellular environment, water tends to flow into the Cell, thereby providing turgor pressure. However, this pressure is equally distributed across the Cell surface. Therefore, for growth to produce Cell shapes other than spheres, Cell Wall expansion must be focused to particular regions. Saccharomyces cerevisiae uses an internal actin cytoskeleton for this purpose (77). During periods of polarized Cell growth, the Wall is loosened by digestive enzymes (e.g., glucanases and chitinases) and expanded at a single point on the Cell surface. Wall remodeling must be carried out in a highly regulated manner—the growth site is loosened enough to allow expansion but not so much as to risk rupture. Yeast Cells invest considerable energy toward biogenesis of the Cell Wall, which comprises some 20 to 30% of the Cell dry weight (243, 313). The major features of the Saccharomyces cerevisiae Cell Wall architecture are now fairly well understood. For a recent review on its molecular organization, the reader is referred to Klis et al. (160). Briefly, the Cell Wall is a layered structure with an electron-transparent inner layer and an electron- dense outer layer (40, 244). The inner layer is comprised of glucan polymers and chitin (N-acetylglucosamine polymers). This layer is constructed mainly (80 to 90%) of 1,3-glucan chains with some 1,6-linked glucan branches. Polymers of 1,6-glucan chains make up most of the remainder of the inner layer (8 to 18%), with chitin chains representing the smallest fraction (1 to 2%). This layer is largely responsible for the mechanical strength and elasticity of the Cell Wall owing primarily to the helical nature of 1,3-glucan chains (270, 313). The outer Cell Wall layer is a lattice of highly glycosylated mannoproteins, which functions to protect the glucan layer from Wall-degrading enzymes (68, 69, 160, 372). It is also important for Cell-Cell recognition during sexual agglutination and biofilm formation (40, 186, 273). Two major classes of Cell surface glycoproteins comprise the outer Cell Wall layer. Members of one class, called glycosylphosphatidylinositol (GPI) proteins, are directed through the secretory pathway to the extraCellular face of the plasma membrane by lipid anchors at their C termini. GPI-proteins are liberated from the plasma membrane by cleavage of their anchors prior to attachment to the Cell Wall (164). Among the approximately 70 GPI-proteins identified in the Saccharomyces cerevisiae genome (41), it is estimated that half reside in the Cell Wall (313). The other major class of Cell Wall proteins is represented by four related polypeptides, Pir1 to Pir4 (152, 228, 330). Although the Pir proteins appear to be linked directly to the 1,3-glucan-chitin lattice, GPI-proteins are generally linked to 1,3-glucan indirectly through a connecting 1,6-glucan chain (160).
Frans M. Klis - One of the best experts on this subject based on the ideXlab platform.
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Cell Wall construction in Saccharomyces cerevisiae
Yeast, 2006Co-Authors: Frans M. Klis, Andre Boorsma, Piet W.j. De GrootAbstract:In this review, we discuss new insights in Cell Wall architecture and Cell Wall construction in the ascomycetous yeast Saccharomyces cerevisiae. Transcriptional profiling studies combined with biochemical work have provided ample evidence that the Cell Wall is a highly adaptable organelle. In particular, the protein population that is anchored to the stress-bearing polysaccharides of the Cell Wall, and forms the interface with the outside world, is highly diverse. This diversity is believed to play an important role in adaptation of the Cell to environmental conditions, in growth mode and in survival. Cell Wall construction is tightly controlled and strictly coordinated with progression of the Cell cycle. This is reflected in the usage of specific Cell Wall proteins during consecutive phases of the Cell cycle and in the recent discovery of a Cell Wall integrity checkpoint. When the Cell is challenged with stress conditions that affect the Cell Wall, a specific transcriptional response is observed that includes the general stress response, the Cell Wall integrity pathway and the calcineurin pathway. This salvage mechanism includes increased expression of putative Cell Wall assemblases and some potential cross-linking Cell Wall proteins, and crucial changes in Cell Wall architecture. We discuss some more enzymes involved in Cell Wall construction and also potential inhibitors of these enzymes. Finally, we use both biochemical and genomic data to infer that the architectural principles used by S. cerevisiae to build its Cell Wall are also used by many other ascomycetous yeasts and also by some mycelial ascomycetous fungi.
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dynamics of Cell Wall structure in saccharomyces cerevisiae
Fems Microbiology Reviews, 2002Co-Authors: Frans M. Klis, Klaas Hellingwerf, Stanley BrulAbstract:The Cell Wall of Saccharomyces cerevisiae is an elastic structure that provides osmotic and physical protection and determines the shape of the Cell. The inner layer of the Wall is largely responsible for the mechanical strength of the Wall and also provides the attachment sites for the proteins that form the outer layer of the Wall. Here we find among others the sexual agglutinins and the flocculins. The outer protein layer also limits the permeability of the Cell Wall, thus shielding the plasma membrane from attack by foreign enzymes and membrane-perturbing compounds. The main features of the molecular organization of the yeast Cell Wall are now known. Importantly, the molecular composition and organization of the Cell Wall may vary considerably. For example, the incorporation of many Cell Wall proteins is temporally and spatially controlled and depends strongly on environmental conditions. Similarly, the formation of specific Cell Wall protein–polysaccharide complexes is strongly affected by external conditions. This points to a tight regulation of Cell Wall construction. Indeed, all five mitogen-activated protein kinase pathways in bakers’ yeast affect the Cell Wall, and additional Cell Wall-related signaling routes have been identified. Finally, some potential targets for new antifungal compounds related to Cell Wall construction are discussed.
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Dynamics of Cell Wall structure in Saccharomyces cerevisiae
FEMS Microbiology Reviews, 2002Co-Authors: Frans M. Klis, Klaas Hellingwerf, P. De Mol, Stanley BrulAbstract:The Cell Wall of Saccharomyces cerevisiae is an elastic structure that provides osmotic and physical protection and determines the shape of the Cell. The inner layer of the Wall is largely responsible for the mechanical strength of the Wall and also provides the attachment sites for the proteins that form the outer layer of the Wall. Here we find among others the sexual agglutinins and the flocculins. The outer protein layer also limits the permeability of the Cell Wall, thus shielding the plasma membrane from attack by foreign enzymes and membrane-perturbing compounds. The main features of the molecular organization of the yeast Cell Wall are now known. Importantly, the molecular composition and organization of the Cell Wall may vary considerably. For example, the incorporation of many Cell Wall proteins is temporally and spatially controlled and depends strongly on environmental conditions. Similarly, the formation of specific Cell Wall protein-polysaccharide complexes is strongly affected by external conditions. This points to a tight regulation of Cell Wall construction. Indeed, all five mitogen-activated protein kinase pathways in bakers' yeast affect the Cell Wall, and additional Cell Wall-related signaling routes have been identified. Finally, some potential targets for new antifungal compounds related to Cell Wall construction are discussed. © 2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.
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The Cell Wall of Fusarium oxysporum
Fungal Genetics and Biology, 1999Co-Authors: E.a.m. Schoffelmeer, Frans M. Klis, J. H. Sietsma, B.j.c. CornelissenAbstract:Sugar analysis of isolated Cell Walls from three formae speciales of Fusarium oxysporum showed that they contained not only glucose and (N-acetyl)-glucosamine, but also mannose, galactose, and uronic acids, presumably originating from Cell Wall glycoproteins. Cell Wall glycoproteins accounted for 50–60% of the total mass of the Wall. X-ray diffraction studies showed the presence of α-1,3-glucan in the alkali-soluble Cell Wall fraction and of β-1,3-glucan and chitin in the alkali-insoluble fraction. Electron microscopy and lectin binding studies indicated that glycoproteins form an external layer covering an inner layer composed of chitin and glucan.
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The contribution of Cell Wall proteins to the organization of the yeast Cell Wall
Biochimica et Biophysica Acta, 1999Co-Authors: Johan C. Kapteyn, Herman Van Den Ende, Frans M. KlisAbstract:Our knowledge of the yeast Cell Wall has increased rapidly in the past few years, allowing for the first time a description of its structure in molecular terms. Two types of Cell Wall proteins (CWPs) have been identified that are covalently linked to β-glucan, namely GPI-CWPs and Pir-CWPs. Both define a characteristic supramolecular complex or structural unit. The GPI building block has the core structure GPI-CWP→β1,6-glucan→β1,3-glucan, which may become extended with one or more chitin chains. The Pir building block is less well characterized, but preliminary evidence points to the structure, Pir-CWP→β1,3-glucan, which probably also may become extended with one or more chitin chains. The molecular architecture of the Cell Wall is not fixed. The Cell can make considerable adjustments to the composition and structure of its Wall, for example, during the Cell cycle or in response to environmental conditions such as nutrient and oxygen availability, temperature, and pH. When the Cell Wall is defective, dramatic changes can occur in its molecular architecture, pointing to the existence of Cell Wall repair mechanisms that compensate for Cell damage. Finally, evidence is emerging that at least to a considerable extent the Cell Wall of Saccharomyces cerevisiae is representative for the Cell Wall of the Ascomycetes.
Elizabeth H. Harris - One of the best experts on this subject based on the ideXlab platform.
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Production of Cell Wall polypeptides by different Cell Wall mutants of the uniCellular green alga Chlamydomonas reinhardtii.
Microbiological Research, 1997Co-Authors: Jürgen Voigt, Bettina Hinkelmann, Elizabeth H. HarrisAbstract:Abstract Three classes of Cell Wall-defective mutants of the uniCellular green alga Chlamydomonas reinhardtii have been described in the literature differing with respect to the amounts of Cell Wall material and its attachment to the plasma membrane, respectively. We have compared the production of the chaotrope-soluble Cell Wall polypeptides by the different mutants. These experiments have been performed by comparative Western-blot analyses using antibodies raised (1) against the deglycosylation products of the insoluble Wall fraction of wild-type Cells, (2) against the deglycosylation product of the ‘150 kDa’ chaotrope-soluble Cell Wall polypeptide and (3) against the carbohydrate side chains of the Chlamydomonas Cell Wall glycoproteins, respectively. Considerably different levels of Cell Wall polypeptides were found in the LiCl-extracts from intact Cells of the various mutant strains containing the apoplastic, chaotrope-soluble Cell Wall glycoproteins. No correlation was found between the amounts and the patterns of Cell Wall glycoproteins present in the LiCl-extracts and the electron microscopical classification of the mutant strains. All the mutant strains were shown to contain the same amounts and patterns of intraCellular Cell Wall precursors as wild-type Cells as revealed by Western-blot analyses of urea-SDS lysates of LiCl-pretreated Cells. These findings indicate that the different mutant strains produce the same set of Cell Wall polypeptides at the same relative amounts as wild-type Cells. However, in the case of some strains belonging to different classes of Cell Wall mutants and showing differential seggregation patterns in crosses, alterations were observed for the pattern of extraCellular Cell Wall polypeptides present in the LiCl-extracts from intact Cells and in the culture medium, respectively.
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Production of Cell Wall polypeptides by different Cell Wall mutants ofthe uniCellular green alga Chlamydomonas reinhardtii
Microbiological Research, 1997Co-Authors: Jürgen Voigt, Bettina Hinkelmann, Elizabeth H. HarrisAbstract:Three classes of Cell Wall-defective mutants of the uniCellular green alga Chlamydomonas reinhardtii have been described in the literature differing with respect to the amounts of Cell Wall material and its attachment to the plasma membrane, respectively. We have compared the production of the chaotrope-soluble Cell Wall polypeptides by the different mutants. These experiments have been performed by comparative Western-blot analyses using antibodies raised (1) against the deglycosylation products of the insoluble Wall fraction of wild-type Cells, (2) against the deglycosylation product of the '150 kDa' chaotrope-soluble Cell Wall polypeptide and (3) against the carbohydrate side chains of the Chlamydomonas Cell Wall glycoproteins, respectively. Considerably different levels of Cell Wall polypeptides were found in the LiCl-extracts from intact Cells of the various mutant strains containing the apoplastic, chaotrope-soluble Cell Wall glycoproteins. No correlation was found between the amounts and the patterns of Cell Wall glycoproteins present in the LiCl-extracts and the electron microscopical classification of the mutant strains. All the mutant strains were shown to contain the same amounts and patterns of intraCellular Cell Wall precursors as wild-type Cells as revealed by Western-blot analyses of urea-SDS lysates of LiCl-pretreated Cells. These findings indicate that the different mutant strains produce the same set of Cell Wall polypeptides at the same relative amounts as wild-type Cells. However, in the case of some strains belonging to different classes of Cell Wall mutants and showing differential seggregation patterns in crosses, alterations were observed for the pattern of extraCellular Cell Wall polypeptides present in the LiCl-extracts from intact Cells and in the culture medium, respectively.
Stephen J. Free - One of the best experts on this subject based on the ideXlab platform.
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Characterization of the Sclerotinia sclerotiorum Cell Wall proteome
Molecular Plant Pathology, 2016Co-Authors: Stephen J. FreeAbstract:Summary We used a proteomic analysis to identify Cell Wall proteins released from Sclerotinia sclerotiorum hyphal and sclerotial Cell Walls via a trifluoromethanesulfonic acid (TFMS) digestion. Cell Walls from hyphae grown in Vogel's glucose medium (a synthetic medium lacking plant materials), from hyphae grown in potato dextrose broth and from sclerotia produced on potato dextrose agar were used in the analysis. Under the conditions used, TFMS digests the glycosidic linkages in the Cell Walls to release intact Cell Wall proteins. The analysis identified 24 glycosylphosphatidylinositol (GPI)-anchored Cell Wall proteins and 30 non-GPI-anchored Cell Wall proteins. We found that the Cell Walls contained an array of Cell Wall biosynthetic enzymes similar to those found in the Cell Walls of other fungi. When comparing the proteins in hyphal Cell Walls grown in potato dextrose broth with those in hyphal Cell Walls grown in the absence of plant material, it was found that a core group of Cell Wall biosynthetic proteins and some proteins associated with pathogenicity (secreted Cellulases, pectin lyases, glucosidases and proteases) were expressed in both types of hyphae. The hyphae grown in potato dextrose broth contained a number of additional proteins (laccases, oxalate decarboxylase, peroxidase, polysaccharide deacetylase and several proteins unique to Sclerotinia and Botrytis) that might facilitate growth on a plant host. A comparison of the proteins in the sclerotial Cell Wall with the proteins in the hyphal Cell Wall demonstrated that sclerotia formation is not marked by a major shift in the composition of Cell Wall protein. We found that the S. sclerotiorum Cell Walls contained 11 Cell Wall proteins that were encoded only in Sclerotinia and Botrytis genomes.
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fungal Cell Wall organization and biosynthesis
Advances in Genetics, 2013Co-Authors: Stephen J. FreeAbstract:The composition and organization of the Cell Walls from Saccharomyces cerevisiae, Candida albicans, Aspergillus fumigatus, Schizosaccharomyces pombe, Neurospora crassa, and Cryptococcus neoformans are compared and contrasted. These Cell Walls contain chitin, chitosan, β-1,3-glucan, β-1,6-glucan, mixed β-1,3-/β-1,4-glucan, α-1,3-glucan, melanin, and glycoproteins as major constituents. A comparison of these Cell Walls shows that there is a great deal of variability in fungal Cell Wall composition and organization. However, in all cases, the Cell Wall components are cross-linked together to generate a Cell Wall matrix. The biosynthesis and properties of each of the major Cell Wall components are discussed. The chitin and glucans are synthesized and extruded into the Cell Wall space by plasma membrane-associated chitin synthases and glucan synthases. The glycoproteins are synthesized by ER-associated ribosomes and pass through the canonical secretory pathway. Over half of the major Cell Wall proteins are modified by the addition of a glycosylphosphatidylinositol anchor. The Cell Wall glycoproteins are also modified by the addition of O-linked oligosaccharides, and their N-linked oligosaccharides are extensively modified during their passage through the secretory pathway. These Cell Wall glycoprotein posttranslational modifications are essential for cross-linking the proteins into the Cell Wall matrix. Cross-linking the Cell Wall components together is essential for Cell Wall integrity. The activities of four groups of cross-linking enzymes are discussed. Cell Wall proteins function as cross-linking enzymes, structural elements, adhesins, and environmental stress sensors and protect the Cell from environmental changes.
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Fungal Cell Wall Organization and Biosynthesis
Advances in Genetics, 2013Co-Authors: Stephen J. FreeAbstract:The composition and organization of the Cell Walls from Saccharomyces cerevisiae, Candida albicans, Aspergillus fumigatus, Schizosaccharomyces pombe, Neurospora crassa, and Cryptococcus neoformans are compared and contrasted. These Cell Walls contain chitin, chitosan, β-1,3-glucan, β-1,6-glucan, mixed β-1,3-/β-1,4-glucan, α-1,3-glucan, melanin, and glycoproteins as major constituents. A comparison of these Cell Walls shows that there is a great deal of variability in fungal Cell Wall composition and organization. However, in all cases, the Cell Wall components are cross-linked together to generate a Cell Wall matrix. The biosynthesis and properties of each of the major Cell Wall components are discussed. The chitin and glucans are synthesized and extruded into the Cell Wall space by plasma membrane-associated chitin synthases and glucan synthases. The glycoproteins are synthesized by ER-associated ribosomes and pass through the canonical secretory pathway. Over half of the major Cell Wall proteins are modified by the addition of a glycosylphosphatidylinositol anchor. The Cell Wall glycoproteins are also modified by the addition of O-linked oligosaccharides, and their N-linked oligosaccharides are extensively modified during their passage through the secretory pathway. These Cell Wall glycoprotein posttranslational modifications are essential for cross-linking the proteins into the Cell Wall matrix. Cross-linking the Cell Wall components together is essential for Cell Wall integrity. The activities of four groups of cross-linking enzymes are discussed. Cell Wall proteins function as cross-linking enzymes, structural elements, adhesins, and environmental stress sensors and protect the Cell from environmental changes. © 2013 Elsevier Inc.
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The structure and synthesis of the fungal Cell Wall
BioEssays, 2006Co-Authors: Shaun M. Bowman, Stephen J. FreeAbstract:The fungal Cell Wall is a dynamic structure that protects the Cell from changes in osmotic pressure and other environmental stresses, while allowing the fungal Cell to interact with its environment. The structure and biosynthesis of a fungal Cell Wall is unique to the fungi, and is therefore an exCellent target for the development of anti-fungal drugs. The structure of the fungal Cell Wall and the drugs that target its biosynthesis are reviewed. Based on studies in a number of fungi, the Cell Wall has been shown to be primarily composed of chitin, glucans, mannans and glycoproteins. The biosynthesis of the various components of the fungal Cell Wall and the importance of the components in the formation of a functional Cell Wall, as revealed through mutational analyses, are discussed. There is strong evidence that the chitin, glucans and glycoproteins are covalently cross-linked together and that the cross-linking is a dynamic process that occurs extraCellularly. BioEssays 28: 799–808, 2006. © 2006 Wiley Periodicals, Inc.
Elisabeth Jamet - One of the best experts on this subject based on the ideXlab platform.
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Cell Wall proteomic of Brachypodium distachyon grains: A focus on Cell Wall remodeling proteins.
Proteomics, 2017Co-Authors: Mathilde Francin-Allami, Virginie Lollier, Helene Rogniaux-Bonaventure, Kahina Merah, Richard Sibout, Fabienne Guillon, Cécile Albenne, Elisabeth Jamet, Marija Pavlovic, Christian LarreAbstract:Cell Walls play key roles during plant development. Following their deposition into the Cell Wall, polysaccharides are continually remodeled according to the growth stage and stress environment to accommodate Cell growth and differentiation. To date, little is known concerning the enzymes involved in Cell Wall remodeling, especially in gramineous and particularly in the grain during development. Here, we investigated the Cell Wall proteome of the grain of Brachypodium distachyon. This plant is a suitable model for temperate cereal crops. Among the 601 proteins identified, 299 were predicted to be secreted. These proteins were distributed into eight functional classes; the class of proteins that act on carbohydrates was the most highly represented. Among these proteins, numerous glycoside hydrolases were found. Expansins and peroxidases, which are assumed to be involved in Cell Wall polysaccharide remodeling, were also identified. Approximately half of the proteins identified in this study were newly discovered in grain and were not identified in the previous proteome analysis conducted using the culms and leaves of B. distachyon. Therefore, the data obtained from all organs of B. distachyon infer a global Cell Wall proteome consisting of 460 proteins. At present, this is the most extensive Cell Wall proteome of a monocot species.
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Isolation of the Cell Wall
Methods of Molecular Biology, 2016Co-Authors: Hervé Canut, Cécile Albenne, Elisabeth JametAbstract:: This chapter describes a method allowing the purification of the Cell Wall for studying both polysaccharides and proteins. The plant primary Cell Wall is mainly composed of polysaccharides (90-95 % in mass) and of proteins (5-10 %). At the end of growth, specialized Cells may synthesize a lignified secondary Wall composed of polysaccharides (about 65 %) and lignin (about 35 %). Due to its composition, the Cell Wall is the Cellular compartment having the highest density and this property is used for its purification. It plays critical roles during plant development and in response to environmental constraints. It is largely used in the food and textile industries as well as for the production of bioenergy. All these characteristics and uses explain why its study as a true Cell compartment is of high interest. The proposed method of purification can be used for large amount of material but can also be downscaled to 500 mg of fresh material. Tools for checking the quality of the Cell Wall preparation, such as protein analysis and microscopy observation, are also provided.
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WallProtDB, a database resource for plant Cell Wall proteomics
Plant Methods, 2015Co-Authors: Hélène San Clemente, Elisabeth JametAbstract:BACKGROUND During the last fifteen years, Cell Wall proteomics has become a major research field with the publication of more than 50 articles describing plant Cell Wall proteomes. The WallProtDB database has been designed as a tool to facilitate the inventory, the interpretation of Cell Wall proteomics data and the comparisons between Cell Wall proteomes. RESULTS WallProtDB (http://www.polebio.lrsv.ups-tlse.fr/WallProtDB/) presently contains 2170 proteins and ESTs identified experimentally in 36 Cell Wall proteomics studies performed on 11 different plant species. Two criteria have to be met for entering WallProtDB. First one is related to the identification of proteins. Only proteins identified in plant with available genomic or ESTs data are considered to ensure unambiguous identification. Second criterion is related to the difficulty to obtain clean Cell Wall fractions. Indeed, since Cell Walls constitute an open compartment difficult to isolate, numerous proteins predicted to be intraCellular and/or having functions inside the Cell have been identified in Cell Wall extracts. Then, except proteins predicted to be plasma membrane proteins, only proteins having a predicted signal peptide and no known intraCellular retention signal are included in the database. In addition, WallProtDB contains information about the strategies used to obtain Cell Wall protein extracts and to identify proteins by mass spectrometry and bioinformatics. Mass spectrometry data are included when available. All the proteins of WallProtDB are linked to ProtAnnDB, another database, which contains structural and functional bioinformatics annotations of proteins as well as links to other databases (Aramemnon, CAZy, Planet, Phytozome). A list of references in the Cell Wall proteomics field is also provided. CONCLUSIONS WallProtDB aims at becoming a Cell Wall proteome reference database. It can be updated at any time on request and provide a support for sharing Cell Wall proteomics data and literature references with researchers interested in plant Cell Wall biology.
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Cell Wall
Plant Proteomics: Technologies Strategies and Applications, 2008Co-Authors: Elisabeth Jamet, Georges Boudart, Cécile Albenne, Hervé Canut, Rafael Pont-lezicaAbstract:This chapter contains sections titled: * Macromolecular Components of the Cell Wall * Cell Wall Layers * Pits and Primary Pit-Fields * Origin of Cell Wall during Cell Division * Growth of the Cell Wall * Expansion of the Primary Cell Wall * Cessation of Wall Expansion * InterCellular Spaces * Plasmodesmata * References
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Cell Wall Proteome
Plant Proteomics, 2007Co-Authors: Zoran Minic, Georges Boudart, Cécile Albenne, Elisabeth Jamet, Hervé Canut, Rafael Pont-lezicaAbstract:In this chapter, we will focus on the contribution of proteomics to the identification and determination of the structure and function of CWPs as well as discussing new perspectives in this area. The great variety of proteins found in the plant Cell Wall is described. Some families, such as glycoside hydrolases, proteases, lectins, and inhibitors of Cell Wall modifying enzymes, are discussed in detail. Examples of the use of proteomic techniques to elucidate the structure of various Cell Wall proteins, especially with post-translational modifications such as Nglycosylations, proline hydroxylation and O-glycosylations, addition of GPI anchors, and phosphorylation, are given. Finally, the emerging understanding of the functions of Cell Wall proteins is discussed, as well as proposals for future research.