Differentiation of the High Night Temperature Response in Leaf Segments of Rice Cultivars with Contrasting Tolerance

High night temperatures (HNT) affect rice yield in the field and induce chlorosis symptoms in leaves in controlled chamber experiments. However, little is known about molecular changes in leaf segments under these conditions. Transcript and metabolite profiling were performed for leaf segments of six rice cultivars with different HNT sensitivity. The metabolite profile of the sheath revealed a lower metabolite abundance compared to segments of the leaf blade. Furthermore, pre-adaptation to stress under control conditions was detected in the sheath, whereas this segment was only slightly affected by HNT. No unique significant transcriptomic changes were observed in the leaf base, including the basal growth zone at HNT conditions. Instead, selected metabolites showed correlations with HNT sensitivity in the base. The middle part and the tip were most highly affected by HNT in sensitive cultivars on the transcriptomic level with higher expression of jasmonic acid signaling related genes, genes encoding enzymes involved in flavonoid metabolism and a gene encoding galactinol synthase. In addition, gene expression of expansins known to improve stress tolerance increased in tolerant and sensitive cultivars. The investigation of the different leaf segments indicated highly segment specific responses to HNT. Molecular key players for HNT sensitivity were identified.

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Expression and function of the cdgD gene, encoding a CHASE–PAS-DGC-EAL domain protein, in Azospirillum brasilense

Scientific Reports ◽

10.1038/s41598-020-80125-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

José Francisco Cruz-Pérez ◽

Roxana Lara-Oueilhe ◽

Cynthia Marcos-Jiménez ◽

Ricardo Cuatlayotl-Olarte ◽

María Luisa Xiqui-Vázquez ◽

...

Keyword(s):

Azospirillum Brasilense ◽

Type Strain ◽

Wild Type Strain ◽

Soil Conditions ◽

Wild Type ◽

Gene Encoding ◽

Wheat Roots ◽

Genes Encoding ◽

In The Wild ◽

Plant Growth Promoting

AbstractThe plant growth-promoting bacterium Azospirillum brasilense contains several genes encoding proteins involved in the biosynthesis and degradation of the second messenger cyclic-di-GMP, which may control key bacterial functions, such as biofilm formation and motility. Here, we analysed the function and expression of the cdgD gene, encoding a multidomain protein that includes GGDEF-EAL domains and CHASE and PAS domains. An insertional cdgD gene mutant was constructed, and analysis of biofilm and extracellular polymeric substance production, as well as the motility phenotype indicated that cdgD encoded a functional diguanylate protein. These results were correlated with a reduced overall cellular concentration of cyclic-di-GMP in the mutant over 48 h compared with that observed in the wild-type strain, which was recovered in the complemented strain. In addition, cdgD gene expression was measured in cells growing under planktonic or biofilm conditions, and differential expression was observed when KNO3 or NH4Cl was added to the minimal medium as a nitrogen source. The transcriptional fusion of the cdgD promoter with the gene encoding the autofluorescent mCherry protein indicated that the cdgD gene was expressed both under abiotic conditions and in association with wheat roots. Reduced colonization of wheat roots was observed for the mutant compared with the wild-type strain grown in the same soil conditions. The Azospirillum-plant association begins with the motility of the bacterium towards the plant rhizosphere followed by the adsorption and adherence of these bacteria to plant roots. Therefore, it is important to study the genes that contribute to this initial interaction of the bacterium with its host plant.

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Structure, expression, chromosomal location and product of the gene encoding Adh2 in Petunia.

Genetics ◽

10.1093/genetics/133.4.999 ◽

1993 ◽

Vol 133 (4) ◽

pp. 999-1007

Author(s):

R G Gregerson ◽

L Cameron ◽

M McLean ◽

P Dennis ◽

J Strommer

Keyword(s):

Chromosomal Location ◽

Higher Plants ◽

Gene Encoding ◽

Genomic Libraries ◽

Regulatory Strategy ◽

Adh1 Gene ◽

Adh Genes ◽

Genes Encoding ◽

Adh Gene ◽

Polymerase Chain

Abstract In most higher plants the genes encoding alcohol dehydrogenase comprise a small gene family, usually with two members. The Adh1 gene of Petunia has been cloned and analyzed, but a second identifiable gene was not recovered from any of three genomic libraries. We have therefore employed the polymerase chain reaction to obtain the major portion of a second Adh gene. From sequence, mapping and northern data we conclude this gene encodes ADH2, the major anaerobically inducible Adh gene of Petunia. The availability of both Adh1 and Adh2 from Petunia has permitted us to compare their structures and patterns of expression to those of the well-studied Adh genes of maize, of which one is highly expressed developmentally, while both are induced in response to hypoxia. Despite their evolutionary distance, evidenced by deduced amino acid sequence as well as taxonomic classification, the pairs of genes are regulated in strikingly similar ways in maize and Petunia. Our findings suggest a significant biological basis for the regulatory strategy employed by these distant species for differential expression of multiple Adh genes.

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Non-Syndromic Dentinogenesis Imperfecta Caused by Mild Mutations in COL1A2

Journal of Personalized Medicine ◽

10.3390/jpm11060526 ◽

2021 ◽

Vol 11 (6) ◽

pp. 526

Author(s):

Yejin Lee ◽

Youn Jung Kim ◽

Hong-Keun Hyun ◽

Jae-Cheoun Lee ◽

Zang Hee Lee ◽

...

Keyword(s):

Collagen Type ◽

Molecular Genetic ◽

Collagen Type I ◽

Type I ◽

Dentinogenesis Imperfecta ◽

Gene Encoding ◽

Korean Families ◽

Whole Exome ◽

Genes Encoding ◽

Candidate Gene Sequencing

Hereditary dentin defects can be categorized as a syndromic form predominantly related to osteogenesis imperfecta (OI) or isolated forms without other non-oral phenotypes. Mutations in the gene encoding dentin sialophosphoprotein (DSPP) have been identified to cause dentinogenesis imperfecta (DGI) Types II and III and dentin dysplasia (DD) Type II. While DGI Type I is an OI-related syndromic phenotype caused mostly by monoallelic mutations in the genes encoding collagen type I alpha 1 chain (COL1A1) and collagen type I alpha 2 chain (COL1A2). In this study, we recruited families with non-syndromic dentin defects and performed candidate gene sequencing for DSPP exons and exon/intron boundaries. Three unrelated Korean families were further analyzed by whole-exome sequencing due to the lack of the DSPP mutation, and heterozygous COL1A2 mutations were identified: c.3233G>A, p.(Gly1078Asp) in Family 1 and c.1171G>A, p.(Gly391Ser) in Family 2 and 3. Haplotype analysis revealed different disease alleles in Families 2 and 3, suggesting a mutational hotspot. We suggest expanding the molecular genetic etiology to include COL1A2 for isolated dentin defects in addition to DSPP.

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CAU-1, a Subclass B3 Metallo-β-Lactamase of Low Substrate Affinity Encoded by an Ortholog Present in the Caulobacter crescentus Chromosome

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.6.1823-1830.2002 ◽

2002 ◽

Vol 46 (6) ◽

pp. 1823-1830 ◽

Cited By ~ 47

Author(s):

Jean-Denis Docquier ◽

Fabrizio Pantanella ◽

Francesco Giuliani ◽

Maria Cristina Thaller ◽

Gianfranco Amicosante ◽

...

Keyword(s):

Caulobacter Crescentus ◽

Hypothetical Protein ◽

Exchange Chromatography ◽

Substrate Affinity ◽

Gene Encoding ◽

Native Form ◽

Significant Similarity ◽

Expression Studies ◽

Genes Encoding ◽

Isoelectric Ph

ABSTRACT The sequenced chromosome of Caulobacter crescentus CB15 encodes a hypothetical protein that exhibits significant similarity (30 to 35% identical residues) to metallo-β-lactamases of subclass B3. An allelic variant of this gene (divergent by 3% of its nucleotides) was cloned in Escherichia coli from C. crescentus type strain DSM4727. Expression studies confirmed the metallo-β-lactamase activity of its product, CAU-1. The enzyme produced in E. coli was purified by two ion-exchange chromatography steps. CAU-1 contains a 29-kDa polypeptide with an alkaline isoelectric pH (>9), and unlike the L1 enzyme of Stenotrophomonas maltophilia, the native form is monomeric. Kinetic analysis revealed a preferential activity toward penicillins, carbapenems, and narrow-spectrum cephalosporins, while oxyimino cephalosporins were poorly or not hydrolyzed. Affinities for the various β-lactams were poor overall (Km values were always >100 μM and often >400 μM). The interaction with divalent ion chelators appeared to occur by a mechanism similar to that prevailing in other members of subclass B3. In C. crescentus, the CAU-1 enzyme is produced independently of β-lactam exposure and, interestingly, the bla CAU determinant is bracketed by three other genes, including two genes encoding enzymes involved in methionine biosynthesis and a gene encoding a putative transcriptional regulator, in an operon-like structure. The CAU-1 enzyme is the first example of a metallo-β-lactamase in a member of the α subdivision of the class Proteobacteria.

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Essential and nonessential histone H2A variants in Tetrahymena thermophila.

Molecular and Cellular Biology ◽

10.1128/mcb.16.8.4305 ◽

1996 ◽

Vol 16 (8) ◽

pp. 4305-4311 ◽

Cited By ~ 81

Author(s):

X Liu ◽

B Li ◽

GorovskyMA

Keyword(s):

Tetrahymena Thermophila ◽

Essential Gene ◽

Histone Variants ◽

Gene Replacement ◽

Histone H2a ◽

Gene Encoding ◽

Genes Encoding ◽

Simple Mass ◽

Essential Function ◽

High Degree

Although variants have been identified for every class of histone, their functions remain unknown. We have been studying the histone H2A variant hv1 in the ciliated protozoan Tetrahymena thermophila. Sequence analysis indicates that hv1 belongs to the H2A.F/Z type of histone variants. On the basis of the high degree of evolutionary conservation of this class of histones, they are proposed to have one or more distinct and essential functions that cannot be performed by their major H2A counterparts. Considerable evidence supports the hypothesis that the hv1 protein in T. thermophila and hv1-like proteins in other eukaryotes are associated with active chromatin. In T. thermophila, simple mass transformation and gene replacement techniques have recently become available. In this report, we demonstrate that either the HTA1 gene or the HTA2 gene, encoding the major H2As, can be completely replaced by disrupted genes in the polyploid, transcriptionally active macronucleus, indicating that neither of the two genes is essential. However, only some of the HTA3 genes encoding hv1 can be replaced by disrupted genes, indicating that the H2A.F/Z type variants have an essential function that cannot be performed by the major H2A genes. Thus, an essential gene in T. thermophila can be defined by the fact that it can be partially, but not completely, eliminated from the polyploid macronucleus. To our knowledge, this study represents the first use of gene disruption technology to study core histone gene function in any organism other than yeast and the first demonstration of an essential gene in T. thermophila using these methods. When a rescuing plasmid carrying a wild-type HTA3 gene was introduced into the T. thermophila cells, the endogenous chromosomal HTA3 could be completely replaced, defining a gene replacement strategy that can be used to analyze the function of essential genes.

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Direct cloning of genes encoding novel xylanases from the human gut

Canadian Journal of Microbiology ◽

10.1139/w04-136 ◽

2005 ◽

Vol 51 (3) ◽

pp. 251-259 ◽

Cited By ~ 42

Author(s):

Hidenori Hayashi ◽

Takashi Abe ◽

Mitsuo Sakamoto ◽

Hiroki Ohara ◽

Toshimichi Ikemura ◽

...

Keyword(s):

Intestinal Bacteria ◽

Fecal Microbiota ◽

Coli Strain ◽

Amino Acid Sequences ◽

Self Organizing Map ◽

Human Gut ◽

Gene Encoding ◽

Genes Encoding ◽

Ph Range ◽

Self Organizing

The aim of this study was to identify a novel 1,4-β-xylanase gene from the mixed genome DNA of human fecal bacteria without bacterial cultivation. Total DNA was isolated from a population of bacteria extracted from fecal microbiota. Using PCR, the gene fragments encoding 5 different family 10 xylanases (xyn10A, xyn10B, xyn10C, xyn10D, and xyn10E) were found. Amino acid sequences deduced from these genes were highly homologous with those of xylanases from anaerobic intestinal bacteria such as Bacteroides spp. and Prevotella spp. Self-organizing map (SOM) analysis revealed that xynA10 was classified into Bacteroidetes. To confirm that one of these genes encodes an active enzyme, a full-length xyn10A gene was obtained using nested primers specific to the internal fragments and random primers. The xyn10A gene encoding the xylanase Xyn10A consists of 1146 bp and encodes a protein of 382 amino acids and a molecular weight of 43 552. Xyn10A was a single module novel xylanase. Xyn10A was purified from a recombinant Escherichia coli strain and characterized. This enzyme was optimally active at 40 °C and stable up to 50 °C at pH 6.5 and over the pH range 4.0–11.0 at 25 °C. In addition, 2 ORFs (ORF1 and ORF2) were identified upstream of xyn10A. These results suggested that many unidentified xylanolytic bacteria exist in the human gut and may contribute to the breakdown of xylan which contains dietary fiber.Key words: xylanase, human gut, fecal microbiota, phylogenetic analysis, self-organizing map.

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Pathogen and Pest Responses Are Altered Due to RNAi-Mediated Knockdown of GLYCOALKALOID METABOLISM 4 in Solanum tuberosum

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-02-17-0033-r ◽

2017 ◽

Vol 30 (11) ◽

pp. 876-885 ◽

Cited By ~ 7

Author(s):

Jamuna Risal Paudel ◽

Charlotte Davidson ◽

Jun Song ◽

Itkin Maxim ◽

Asaph Aharoni ◽

...

Keyword(s):

Solanum Tuberosum ◽

Biosynthetic Pathway ◽

Plant Protection ◽

Insect Pest ◽

Metabolite Profile ◽

Gene Encoding ◽

Rnai Line ◽

Leaf Consumption ◽

Insect Mortality ◽

Potato Growth

Steroidal glycoalkaloids (SGAs) are major secondary metabolites constitutively produced in cultivated potato Solanum tuberosum, and α-solanine and α-chaconine are the most abundant SGAs. SGAs are toxic to humans at high levels but their role in plant protection against pests and pathogens is yet to be established. In this study, levels of SGAs in potato were reduced by RNA interference (RNAi)-mediated silencing of GLYCOALKALOID METABOLISM 4 (GAME4)—a gene encoding cytochrome P450, involved in an oxidation step in the conversion of cholesterol to SGA aglycones. Two GAME4 RNAi lines, T8 and T9, were used to investigate the effects of manipulation of the SGA biosynthetic pathway in potato. Growth and development of an insect pest, Colorado potato beetle (CPB), were affected in these lines. While no effect on CPB leaf consumption or weight gain was observed, early instar larval death and accelerated development of the insect was found while feeding on leaves of GAME4 RNAi lines. Modulation of SGA biosynthetic pathway in GAME4 RNAi plants was associated with a larger alteration to the metabolite profile, including increased levels of one or both the steroidal saponins or phytoecdysteroids, which could affect insect mortality as well as development time. Colonization by Verticillium dahliae on GAME4 RNAi plants was also tested. There were increased pathogen levels in the T8 GAME4 RNAi line but not in the T9. Metabolite differences between T8 and T9 were found and may have contributed to differences in V. dahliae infection. Drought responses created by osmotic stress were not affected by modulation of SGA biosynthetic pathway in potato.

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Platform Engineering of Corynebacterium glutamicum with Reduced Pyruvate Dehydrogenase Complex Activity for Improved Production of l-Lysine, l-Valine, and 2-Ketoisovalerate

Applied and Environmental Microbiology ◽

10.1128/aem.01741-13 ◽

2013 ◽

Vol 79 (18) ◽

pp. 5566-5575 ◽

Cited By ~ 64

Author(s):

Jens Buchholz ◽

Andreas Schwentner ◽

Britta Brunnenkan ◽

Christina Gabris ◽

Simon Grimm ◽

...

Keyword(s):

Corynebacterium Glutamicum ◽

Pyruvate Dehydrogenase ◽

Pyruvate Dehydrogenase Complex ◽

Fed Batch ◽

Complex Activity ◽

Gene Encoding ◽

Content Type ◽

Genes Encoding ◽

Cell Densities ◽

Dehydrogenase Complex

ABSTRACTExchange of the nativeCorynebacterium glutamicumpromoter of theaceEgene, encoding the E1p subunit of the pyruvate dehydrogenase complex (PDHC), with mutateddapApromoter variants led to a series ofC. glutamicumstrains with gradually reduced growth rates and PDHC activities. Upon overexpression of thel-valine biosynthetic genesilvBNCE, all strains producedl-valine. Among these strains,C. glutamicum aceEA16 (pJC4ilvBNCE) showed the highest biomass and product yields, and thus it was further improved by additional deletion of thepqoandppcgenes, encoding pyruvate:quinone oxidoreductase and phosphoenolpyruvate carboxylase, respectively. In fed-batch fermentations at high cell densities,C. glutamicum aceEA16 Δpqo Δppc(pJC4ilvBNCE) produced up to 738 mM (i.e., 86.5 g/liter)l-valine with an overall yield (YP/S) of 0.36 mol per mol of glucose and a volumetric productivity (QP) of 13.6 mM per h [1.6 g/(liter × h)]. Additional inactivation of the transaminase B gene (ilvE) and overexpression ofilvBNCDinstead ofilvBNCEtransformed thel-valine-producing strain into a 2-ketoisovalerate producer, excreting up to 303 mM (35 g/liter) 2-ketoisovalerate with aYP/Sof 0.24 mol per mol of glucose and aQPof 6.9 mM per h [0.8 g/(liter × h)]. The replacement of theaceEpromoter by thedapA-A16 promoter in the twoC. glutamicuml-lysine producers DM1800 and DM1933 improved the production by 100% and 44%, respectively. These results demonstrate thatC. glutamicumstrains with reduced PDHC activity are an excellent platform for the production of pyruvate-derived products.

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The Bartonella vinsonii subsp. arupensis Immunodominant Surface Antigen BrpA Gene, Encoding a 382-Kilodalton Protein Composed of Repetitive Sequences, Is a Member of a Multigene Family Conserved among Bartonella Species

Infection and Immunity ◽

10.1128/iai.73.5.3128-3136.2005 ◽

2005 ◽

Vol 73 (5) ◽

pp. 3128-3136 ◽

Cited By ~ 14

Author(s):

Robert D. Gilmore ◽

Travis M. Bellville ◽

Steven L. Sviat ◽

Michael Frace

Keyword(s):

Bartonella Henselae ◽

Repetitive Sequences ◽

Expression Library ◽

Gene Encoding ◽

Significant Similarity ◽

Bartonella Quintana ◽

Genomic Expression ◽

Genes Encoding ◽

Multiple Regions ◽

Adhesin Protein

ABSTRACT Bartonella proteins that elicit an antibody response during an infection are poorly defined; therefore, to characterize antigens recognized by the host, a Bartonella genomic expression library was screened with serum from an infected mouse. This process led to the discovery of a Bartonella vinsonii subsp. arupensis gene encoding a 382-kDa protein, part of a gene family encoding large proteins, each containing multiple regions of repetitive segments. The genes were termed brpA to -C (bartonella repeat protein) and bore significant similarity to genes encoding the BadA adhesin protein and members of the variably expressed outer membrane protein family of proteins from Bartonella henselae and Bartonella quintana, respectively.

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Replication Region Analysis Reveals Non-lambdoid Shiga Toxin Converting Bacteriophages

Frontiers in Microbiology ◽

10.3389/fmicb.2021.640945 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ann-Katrin Llarena ◽

Marina Aspholm ◽

Kristin O’Sullivan ◽

Grzegorz Wêgrzyn ◽

Toril Lindbäck

Keyword(s):

Shiga Toxin ◽

Gene Arrangement ◽

Gene Encoding ◽

Lambdoid Phage ◽

Virulence Potential ◽

Genes Encoding ◽

Large Outbreak ◽

Replication Region ◽

Family Based ◽

Novel Strategy

Shiga toxin is the major virulence factor of enterohemorrhagic Escherichia coli (EHEC), and the gene encoding it is carried within the genome of Shiga toxin-converting phages (Stx phages). Numerous Stx phages have been sequenced to gain a better understanding of their contribution to the virulence potential of EHEC. The Stx phages are classified into the lambdoid phage family based on similarities in lifestyle, gene arrangement, and nucleotide sequence to the lambda phages. This study explores the replication regions of non-lambdoid Stx phages that completely lack the O and P genes encoding the proteins involved in initiating replication in the lambdoid phage genome. Instead, they carry sequences encoding replication proteins that have not been described earlier, here referred to as eru genes (after EHEC phage replication unit genes). This study identified three different types of Eru-phages, where the Eru1-type is carried by the highly pathogenic EHEC strains that caused the Norwegian O103:H25 outbreak in 2006 and the O104:H4 strain that caused the large outbreak in Europe in 2011. We show that Eru1-phages exhibit a less stable lysogenic state than the classical lambdoid Stx phages. As production of phage particles is accompanied by production of Stx toxin, the Eru1-phage could be associated with a high-virulence phenotype of the host EHEC strain. This finding emphasizes the importance of classifying Stx phages according to their replication regions in addition to their Stx-type and could be used to develop a novel strategy to identify highly virulent EHEC strains for improved risk assessment and management.

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