scholarly journals Chitin in Diatoms and Its Association with the Cell Wall

2009 ◽  
Vol 8 (7) ◽  
pp. 1038-1050 ◽  
Author(s):  
Colleen A. Durkin ◽  
Thomas Mock ◽  
E. Virginia Armbrust
Keyword(s):  
Cell Wall ◽  
Silicic Acid ◽  
Expression Patterns ◽  
Transcript Abundance ◽  
Thalassiosira Pseudonana ◽  
Protein Domain ◽  
Chitin Synthase ◽  
Short Term ◽  
Chitin Synthases ◽  
Genes Encoding

ABSTRACT Chitin is a globally abundant polymer widely distributed throughout eukaryotes that has been well characterized in only a few lineages. Diatoms are members of the eukaryotic lineage of stramenopiles. Of the hundreds of diatom genera, two produce long fibers of chitin that extrude through their cell walls of silica. We identify and describe here genes encoding putative chitin synthases in a variety of additional diatom genera, indicating that the ability to produce chitin is more widespread and likely plays a more central role in diatom biology than previously considered. Diatom chitin synthases fall into four phylogenetic clades. Protein domain predictions and differential gene expression patterns provide evidence that chitin synthases have multiple functions within a diatom cell. Thalassiosira pseudonana possesses six genes encoding three types of chitin synthases. Transcript abundance of the gene encoding one of these chitin synthase types increases when cells resume division after short-term silicic acid starvation and during short-term limitation by silicic acid or iron, two nutrient conditions connected in the environment and known to affect the cell wall. During long-term silicic acid starvation transcript abundance of this gene and one additional chitin synthase gene increased at the same time a chitin-binding lectin localized to the girdle band region of the cell wall. Together, these results suggest that the ability to produce chitin is more widespread in diatoms than previously thought and that a subset of the chitin produced by diatoms is associated with the cell wall.

Phloem fibres as motors of gravitropic behaviour of flax plants: level of transcriptome

2018 ◽  
Vol 45 (2) ◽  
pp. 203 ◽  
Author(s):  
Oleg Gorshkov ◽  
Natalia Mokshina ◽  
Nadezda Ibragimova ◽  
Marina Ageeva ◽  
Natalia Gogoleva ◽  
...  
Keyword(s):  
Cell Wall ◽  
Large Scale ◽  
Turgor Pressure ◽  
Control Plant ◽  
Transcriptome Profiling ◽  
Transcript Abundance ◽  
Regulatory Elements ◽  
Wall Structure ◽  
Vertical Position ◽  
Genes Encoding

Restoration of stem vertical position after plant inclination is a widely spread version of plant orientation in accordance with gravity vector direction. Gravitropic behaviour of flax plants involves the formation of curvature in stem region that has ceased elongation long in advance of stem inclination. The important participants of such behaviour are phloem fibres with constitutively formed tertiary cell wall (G-layer). We performed the large-scale transcriptome profiling of phloem fibres isolated from pulling and opposite sides of gravitropic curvature and compared with control plant fibres. Significant changes in transcript abundance take place for genes encoding proteins of several ion channels, transcription factors and other regulating elements. The largest number of upregulated genes belonged to the cell wall category; many of those were specifically upregulated in fibres of pulling stem side. The obtained data permit to suggest the mechanism of fibre participation in gravitropic reaction that involves the increase of turgor pressure and the rearrangements of cell wall structure in order to improve contractile properties, and to identify the regulatory elements that operate specifically in the fibres of the pulling stem side making gelatinous phloem fibres an important element of gravitropic response in herbaceous plants.

scholarly journals A Chitin Synthase and Its Regulator Protein Are Critical for Chitosan Production and Growth of the Fungal Pathogen Cryptococcus neoformans

2005 ◽  
Vol 4 (11) ◽  
pp. 1902-1912 ◽  
Author(s):  
Isaac R. Banks ◽  
Charles A. Specht ◽  
Maureen J. Donlin ◽  
Kimberly J. Gerik ◽  
Stuart M. Levitz ◽  
...  
Keyword(s):  
Cell Wall ◽  
Cryptococcus Neoformans ◽  
Fungal Pathogen ◽  
Liquid Culture ◽  
Chitin Synthase ◽  
Yeast Cells ◽  
Chitin Synthesis ◽  
Chitin Synthases ◽  
Regulator Protein ◽  
Chitin And Chitosan

ABSTRACT Chitin is an essential component of the cell wall of many fungi. Chitin also can be enzymatically deacetylated to chitosan, a more flexible and soluble polymer. Cryptococcus neoformans is a fungal pathogen that causes cryptococcal meningoencephalitis, particularly in immunocompromised patients. In this work, we show that both chitin and chitosan are present in the cell wall of vegetatively growing C. neoformans yeast cells and that the levels of both rise dramatically as cells grow to higher density in liquid culture. C. neoformans has eight putative chitin synthases, and strains with any one chitin synthase deleted are viable at 30°C. In addition, C. neoformans genes encode three putative regulator proteins, which are homologs of Saccharomyces cerevisiae Skt5p. None of these three is essential for viability. However, one of the chitin synthases (Chs3) and one of the regulators (Csr2) are important for growth. Cells with deletions in either CHS3 or CSR2 have several shared phenotypes, including sensitivity to growth at 37°C. The similarity of their phenotypes also suggests that Csr2 specifically regulates chitin synthesis by Chs3. Lastly, both chs3Δ and the csr2Δ mutants are defective in chitosan production, predicting that Chs3-Csr2 complex with chitin deacetylases for conversion of chitin to chitosan. These data suggest that chitin synthesis could be an excellent antifungal target.

scholarly journals Targeting of proteins to the cell wall of the diatom Thalassiosira pseudonana

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Neri Fattorini ◽  
Uwe G. Maier
Keyword(s):  
Cell Wall ◽  
Molecular Level ◽  
Expression Patterns ◽  
Ecological Impact ◽  
Thalassiosira Pseudonana ◽  
Cell Wall Proteins ◽  
Cell Wall Formation ◽  
Wall Formation ◽  
Intracellular Targeting ◽  
Synchronized Cultures

AbstractDiatoms are unicellular phototrophic organisms with huge ecological impact. Characteristic for these organisms is their peculiar cell wall, which is composed of inorganic and organic components. Cell wall formation is a highly complex and orchestrated process, and in the last years has been studied intensively, also on the molecular level. Here, we review on the cell wall proteins of diatoms, with a focus on the species Thalassiosira pseudonana. We report on the expression patterns of these proteins in synchronized cultures, as well as their modifications and intracellular targeting.

scholarly journals ChsVb, a Class VII Chitin Synthase Involved in Septation, Is Critical for Pathogenicity in Fusarium oxysporum

2007 ◽  
Vol 7 (1) ◽  
pp. 112-121 ◽  
Author(s):  
Magdalena Martín-Urdíroz ◽  
M. Isabel G. Roncero ◽  
José Antonio González-Reyes ◽  
Carmen Ruiz-Roldán
Keyword(s):  
Cell Wall ◽  
Fusarium Oxysporum ◽  
Tomato Fruit ◽  
Infection Process ◽  
Chitin Synthase ◽  
Fungal Cell ◽  
Myosin Motor ◽  
Cell Wall Assembly ◽  
Chitin Synthases ◽  
Wall Assembly

ABSTRACT A new myosin motor-like chitin synthase gene, chsVb, has been identified in the vascular wilt fungus Fusarium oxysporum f. sp. lycopersici. Phylogenetic analysis of the deduced amino acid sequence of the chsVb chitin synthase 2 domain (CS2) revealed that ChsVb belongs to class VII chitin synthases. The ChsVb myosin motor-like domain (MMD) is shorter than the MMD of class V chitin synthases and does not contain typical ATP-binding motifs. Targeted disrupted single (ΔchsVb) and double (ΔchsV ΔchsVb) mutants were unable to infect and colonize tomato plants or grow invasively on tomato fruit tissue. These strains were hypersensitive to compounds that interfere with fungal cell wall assembly, produced lemon-like shaped conidia, and showed swollen balloon-like structures in hyphal subapical regions, thickened walls, aberrant septa, and intrahyphal hyphae. Our results suggest that the chsVb gene is likely to function in polarized growth and confirm the critical importance of cell wall integrity in the complex infection process of this fungus.

scholarly journals Gene Expression Patterns for Proteins With Lectin Domains in Flax Stem Tissues Are Related to Deposition of Distinct Cell Wall Types

2021 ◽  
Vol 12 ◽  
Author(s):  
Natalia Petrova ◽  
Alsu Nazipova ◽  
Oleg Gorshkov ◽  
Natalia Mokshina ◽  
Olga Patova ◽  
...  
Keyword(s):  
Cell Wall ◽  
Higher Plants ◽  
Expression Patterns ◽  
Transcript Level ◽  
Genome Wide ◽  
Distinct Cell ◽  
A Genome ◽  
Genes Encoding ◽  
Genome Wide Search ◽  
Encoding Genes

The genomes of higher plants encode a variety of proteins with lectin domains that are able to specifically recognize certain carbohydrates. Plants are enriched in a variety of potentially complementary glycans, many of which are located in the cell wall. We performed a genome-wide search for flax proteins with lectin domains and compared the expression of the encoding genes in different stem tissues that have distinct cell wall types with different sets of major polysaccharides. Over 400 genes encoding proteins with lectin domains that belong to different families were revealed in the flax genome; three quarters of these genes were expressed in stem tissues. Hierarchical clustering of the data for all expressed lectins grouped the analyzed samples according to their characteristic cell wall type. Most lectins differentially expressed in tissues with primary, secondary, and tertiary cell walls were predicted to localize at the plasma membrane or cell wall. These lectins were from different families and had various architectural types. Three out of four flax genes for proteins with jacalin-like domains were highly upregulated in bast fibers at the stage of tertiary cell wall deposition. The dynamic changes in transcript level of many genes for lectins from various families were detected in stem tissue over the course of gravitropic response induced by plant gravistimulation. The data obtained in this study indicate a large number of lectin-mediated events in plants and provide insight into the proteins that take part in tissue specialization and reaction to abiotic stress.

scholarly journals Identification and expression analysis of the glycosyltransferase GT43 family members in bamboo reveal their potential function in xylan biosynthesis during rapid growth

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhen Li ◽  
Xinyue Wang ◽  
Kebin Yang ◽  
Chenglei Zhu ◽  
Tingting Yuan ◽  
...  
Keyword(s):  
Cell Wall ◽  
Rapid Growth ◽  
Expression Patterns ◽  
Staining Intensity ◽  
Moso Bamboo ◽  
Strong Positive Correlation ◽  
Abiotic Stress Response ◽  
Bamboo Shoots ◽  
Genes Encoding ◽  
Xylan Biosynthesis

Abstract Background Xylan is one of the most abundant hemicelluloses and can crosslink cellulose and lignin to increase the stability of cell walls. A number of genes encoding glycosyltransferases play vital roles in xylan biosynthesis in plants, such as those of the GT43 family. However, little is known about glycosyltransferases in bamboo, especially woody bamboo which is a good substitute for timber. Results A total of 17 GT43 genes (PeGT43–1 ~ PeGT43–17) were identified in the genome of moso bamboo (Phyllostachys edulis), which belong to three subfamilies with specific motifs. The phylogenetic and collinearity analyses showed that PeGT43s may have undergone gene duplication, as a result of collinearity found in 12 pairs of PeGT43s, and between 17 PeGT43s and 10 OsGT43s. A set of cis-acting elements such as hormones, abiotic stress response and MYB binding elements were found in the promoter of PeGT43s. PeGT43s were expressed differently in 26 tissues, among which the highest expression level was found in the shoots, especially in the rapid elongation zone and nodes. The genes coexpressed with PeGT43s were annotated as associated with polysaccharide metabolism and cell wall biosynthesis. qRT–PCR results showed that the coexpressed genes had similar expression patterns with a significant increase in 4.0 m shoots and a peak in 6.0 m shoots during fast growth. In addition, the xylan content and structural polysaccharide staining intensity in bamboo shoots showed a strong positive correlation with the expression of PeGT43s. Yeast one-hybrid assays demonstrated that PeMYB35 could recognize the 5′ UTR/promoter of PeGT43–5 by binding to the SMRE cis-elements. Conclusions PeGT43s were found to be adapted to the requirement of xylan biosynthesis during rapid cell elongation and cell wall accumulation, as evidenced by the expression profile of PeGT43s and the rate of xylan accumulation in bamboo shoots. Yeast one-hybrid analysis suggested that PeMYB35 might be involved in xylan biosynthesis by regulating the expression of PeGT43–5 by binding to its 5′ UTR/promoter. Our study provides a comprehensive understanding of PeGT43s in moso bamboo and lays a foundation for further functional analysis of PeGT43s for xylan biosynthesis during rapid growth.

scholarly journals Identification of Candidate Genes Involved in Fruit Ripening and Crispness Retention Through Transcriptome Analyses of a ‘Honeycrisp’ Population

Plants ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1335
Author(s):  
Hsueh-Yuan Chang ◽  
Cindy B. S. Tong
Keyword(s):  
Cell Wall ◽  
Fruit Ripening ◽  
Molecular Mechanisms ◽  
Expression Patterns ◽  
Differentially Expressed ◽  
Rna Seq ◽  
Phenotypic Differences ◽  
Genes Encoding ◽  
A Cell ◽  
Phenotypic Groups

Crispness retention is a postharvest trait that fruit of the ’Honeycrisp’ apple and some of its progeny possess. To investigate the molecular mechanisms of crispness retention, progeny individuals derived from a ’Honeycrisp’ × MN1764 population with fruit that either retain crispness (named “Retain”), lose crispness (named “Lose”), or that are not crisp at harvest (named “Non-crisp”) were selected for transcriptomic comparisons. Differentially expressed genes (DEGs) were identified using RNA-Seq, and the expression levels of the DEGs were validated using nCounter®. Functional annotation of the DEGs revealed distinct ripening behaviors between fruit of the “Retain” and “Non-crisp” individuals, characterized by opposing expression patterns of auxin- and ethylene-related genes. However, both types of genes were highly expressed in the fruit of “Lose” individuals and ’Honeycrisp’, which led to the potential involvements of genes encoding auxin-conjugating enzyme (GH3), ubiquitin ligase (ETO), and jasmonate O-methyltransferase (JMT) in regulating fruit ripening. Cell wall-related genes also differentiated the phenotypic groups; greater numbers of cell wall synthesis genes were highly expressed in fruit of the “Retain” individuals and ’Honeycrisp’ when compared with “Non-crisp” individuals and MN1764. On the other hand, the phenotypic differences between fruit of the “Retain” and “Lose” individuals could be attributed to the functioning of fewer cell wall-modifying genes. A cell wall-modifying gene, MdXTH, was consistently identified as differentially expressed in those fruit over two years in this study, so is a major candidate for crispness retention.

The transcript abundance of an expansin gene in ripe sapodilla (Manilkara zapota) fruit is negatively regulated by ethylene

2008 ◽  
Vol 35 (12) ◽  
pp. 1205 ◽  
Author(s):  
Sutin Kunyamee ◽  
Saichol Ketsa ◽  
Wachiraya Imsabai ◽  
Wouter G. van Doorn
Keyword(s):  
Cell Wall ◽  
Transcript Abundance ◽  
Fruit Softening ◽  
Fruit Firmness ◽  
Mature Fruit ◽  
Cell Wall Loosening ◽  
Manilkara Zapota ◽  
Genes Encoding ◽  
Low Threshold ◽  
Wall Loosening

After harvest, mature fruit of sapodilla (Manilkara zapota van Royen) exhibit rapid softening. The decrease in fruit firmness was hastened by ethylene and delayed by 1-methylcyclopropene (1-MCP). Two genes encoding expansins (called MzEXP1 and MzEXP2) were isolated. In both cultivars studied (Makok-Yai and Kra-Suay), MzEXP1 was transiently expressed early during fruit development on the plant. This suggests that it is involved in cell wall loosening during early fruit growth. In cv. Makok-Yai, MzEXP2 was expressed between 1 day before harvest and day 4 after harvest. In cv. Kra-Suay, the expression of MzEXP2 started 8 weeks before the normal harvest stage, and ended on day 3 after harvest. When the fruit of both cultivars was treated with ethylene (50 µL L−1 for 20 h at 25°C) just after harvest, the expression of MzEXP2 became undetectable. After treatment with 1-MCP MzEXP2 mRNA was highly abundant until day 5 after harvest, when in controls the transcript abundance had become undetectable. The onset of MzEXP2 expression seems not regulated by ethylene, as the concomitant ethylene levels are very low. The data strongly indicate that the decrease of MzEXP2 transcript abundance is due to ethylene production by the fruit, which is by then high. The expression of MzEXP2 ceased, both in controls and in ethylene-treated material, when the fruit had reached a rather low threshold firmness. The data suggest that the protein has a supporting and cooperative role in fruit softening.

scholarly journals A differential expression of receptors mediating receptor-mediated transcytosis (RMT) in brain microvessels, brain parenchyma and peripheral tissues of the mouse and the human

2020 ◽  
Author(s):  
Wandong Zhang ◽  
Qing Yan Liu ◽  
Arsalan S. Haqqani ◽  
Sonia Leclerc ◽  
Joy Lei ◽  
...  
Keyword(s):  
Human Brain ◽  
Leptin Receptor ◽  
Expression Patterns ◽  
Transcript Abundance ◽  
Brain Parenchyma ◽  
Immunofluorescent Staining ◽  
Peripheral Tissues ◽  
Brain Microvessels ◽  
Genes Encoding ◽  
The Brain

Abstract Receptor-mediated transcytosis (RMT) is a principal pathway for transport of macromolecules essential for brain function across the blood-brain barrier (BBB). Antibodies or peptide ligands which bind RMT receptors are often co-opted for brain delivery of biotherapeutics. A constitutively recycling transferrin receptor (TfR) is a prototype receptor utilized to shuttle therapeutic cargos across the BBB. Several other BBB-expressed receptors have been shown to mediate transcytosis of ligands including insulin receptor (INSR) and insulin-like growth factor-1 receptor (IGF1R), lipid transporters LRP1, LDLR, LRP8 and TMEM30A, solute carrier family transporter LAT1 (subunit CD98hc) and leptin receptor (LEPR). In this study, we analyzed expression patterns of genes encoding RMT receptors in isolated brain microvessels, the brain and peripheral organs of the mouse and the human using RNAseq approach. IGF1R, INSR and LRP8 were highly enriched in the mouse brain microvessels compared to peripheral tissues. In the human brain microvessels only INSR was enriched compared to either the brain or the lung. The expression levels of LRP1, IGF1R, LRP8 and TFRC were significantly higher in the mouse compared to the human brain microvessels. The protein expression of these receptors analyzed by quantitative Western blot and immunofluorescent staining of the brain microvessels correlated with their transcript abundance. This study provides a molecular transcriptomics map of key RMT receptors in mouse and human brain microvessels and peripheral tissues, important sot translational studies of biodistribution, efficacy and safety of antibodies developed against these receptors.

Sign in / Sign up

Export Citation Format

Share Document