Marc De Block - Academia.edu (original) (raw)
Papers by Marc De Block
International Journal of Biochemistry, 1988
Plant Physiology and Biochemistry, Oct 1, 2002
At present, there is no general laboratory assay described that allows quantification of the yiel... more At present, there is no general laboratory assay described that allows quantification of the yield potential of plant lines obtained in breeding or research programmes. The only way to evaluate the performance of a plant line is by greenhouse and field trials over several years on different locations. In this paper, an in vitro physiological method is described that allows
Proceedings of the National Academy of Sciences of the United States of America, Sep 18, 2007
Archives of Physiology and Biochemistry, 1996
Springer eBooks, 1988
Phosphinotricin (PPT) is a new non-selective contact herbicide. It is an analogous of glutamate a... more Phosphinotricin (PPT) is a new non-selective contact herbicide. It is an analogous of glutamate and acts as an irreversible inhibitor of the plant glutamine synthetase. The compound is obtained by chemical synthesis (BastaR, Hoechst AG) or naturally produced by some microorganisms as part of a tripeptide antibiotic — e.g. the tripeptide bialaphos from Streptomyces hyqroscopicus (HerbiaceR, Meiji Seika Ltd).
Physiologia Plantarum, May 1, 1990
The attempts to manipulate organelle DNA of higher plants have not yet been succesfull. Although ... more The attempts to manipulate organelle DNA of higher plants have not yet been succesfull. Although some Agrobacterium mediated and direct gene transfer experi‐ments suggested that chloroplasts of Nicotiana tabacum could be transformed, these experiments could not be reproduced. New transformation techniques have emerged: laser‐injection, microinjection and high velocity microprojectiles. The biolistic ex‐periments with Chlamydomonas made it clear that organelle DNA can support introduced DNA fragments by homologous recombination. In view of these devel‐opments, we describe the parameters and new possibilities for chloroplast trans‐formation of higher plants.
Agronomy, Feb 18, 2019
Two of the major pathways involved in induced defense of plants against pathogens include the sal... more Two of the major pathways involved in induced defense of plants against pathogens include the salicylic acid (SA)-and jasmonic acid (JA)-mediated pathways that act mainly against biotrophs and necrotrophs, respectively. However, some necrotrophic pathogens, such as Botrytis cinerea, actively induce the SA pathway, resulting in cell death that allows the pathogen to proliferate in the plant. Starting from an isogenic canola (Brassica napus) line, epilines were selected with a reduced sensitivity to SA. The genes belonging to the SA pathway had an altered transcription profile in the SA-tolerant lines, when treated with SA. Besides the already known genes of the SA pathway, new SA target genes were identified, creating possibilities to better understand the plant defense mechanism against pathogens. The SA-tolerant line with the lowest SA-induced gene expression is tolerant to Botrytis cinerea. When treated with SA, this line has also a reduced histone modification (histone H3 lysine 4 trimethylation) at the genes at the start of the SA pathway.
The EMBO Journal, Jun 1, 1985
A chimeric gene consisting of the promoter region of the nopaline synthase gene (Pnos) fused to t... more A chimeric gene consisting of the promoter region of the nopaline synthase gene (Pnos) fused to the coding sequence of the chloramphenicol acetyltransferase gene (cat gene) of Tn9 was introduced by co-cultivation in tobacco protoplasts followed by selection with 10 ,g/ml chloramphenicol. The chloramphenicol-resistant plants derived from these selected calli were unable to transmit the CmR phenotype through pollen. A typically maternal inheritance pattern was observed. Southern blot analysis showed that the chimeric Pnos-cat gene was present in the chloroplasts of these resistant plants. Furthermore, the chloramphenicol acetyltransferase activity was shown to be associated with the chloroplast fraction. These observations are the first proof that the Agrobacterium Tiplasmid vectors can be used to introduce genes in chloroplasts.
Biochemical Society Transactions, Nov 1, 1996
Plant DNA Infectious Agents, 1987
Reproducible methods, allowing the introduction of defined DNA fragments in the plant nuclear gen... more Reproducible methods, allowing the introduction of defined DNA fragments in the plant nuclear genome, are presently available (see previous chapters in this volume) and are contributing significantly to the experimental analysis of the gene structure-function relationships governing regulated gene-expression in plants.
Agronomy, 2019
Two of the major pathways involved in induced defense of plants against pathogens include the sal... more Two of the major pathways involved in induced defense of plants against pathogens include the salicylic acid (SA)- and jasmonic acid (JA)-mediated pathways that act mainly against biotrophs and necrotrophs, respectively. However, some necrotrophic pathogens, such as Botrytis cinerea, actively induce the SA pathway, resulting in cell death that allows the pathogen to proliferate in the plant. Starting from an isogenic canola (Brassica napus) line, epilines were selected with a reduced sensitivity to SA. The genes belonging to the SA pathway had an altered transcription profile in the SA-tolerant lines, when treated with SA. Besides the already known genes of the SA pathway, new SA target genes were identified, creating possibilities to better understand the plant defense mechanism against pathogens. The SA-tolerant line with the lowest SA-induced gene expression is tolerant to Botrytis cinerea. When treated with SA, this line has also a reduced histone modification (histone H3 lysine...
The EMBO Journal, 1994
2Corresponding author Communicated by M.Van Montagu In Arabidopsis, mutation at PFL causes pointe... more 2Corresponding author Communicated by M.Van Montagu In Arabidopsis, mutation at PFL causes pointed first leaves, reduced fresh weight and growth retardation. We have cloned the wild-type PFL gene by T-DNA tagging, and demonstrate that it complements the mutant phenotype. PFL codes for ribosomal protein S18, based on the high homology with rat S18 and on purification of S18-equivalent peptides from plant ribosomes. pfl represents the first mutation in eukaryotic S18 proteins or their S13 prokaryotic counterparts, involved in translation initiation. Arabidopsis contains three S18 gene copies dispersed in the genetic map; they are all transcribed and code for completely identical proteins. No transcript is detected from the mutated gene, S18A. The activity of the S18A promoter is restricted to meristems, with a markedly high expression at the embryonic heart stage, and to wounding sites. This means that plants activate an extra copy of this ribosomal protein gene in tissues with cell division activity. We postulate that in meristematic tissues plants use transcriptional control to synthesize extra ribosomes to increase translational efficiency. In analogy with this, an additional, developmentally regulated gene copy might be expected for all ribosomal proteins.
Agronomy, 2018
Epigenetics offers important opportunities in breeding to improve the potential yield in a wide v... more Epigenetics offers important opportunities in breeding to improve the potential yield in a wide variety of crops. Starting from a pure breeder seed lot of a rice (Oryza sativa ssp. indica) inbred population, repeated testing for improved cellular respiration rates and energy use efficiency (EUE) over three generations identified performant epilines with distinct epigenetic signatures and with improved seed yield in field trials. Epiline DNA methylomes were characterized by genome-wide bisulfite sequencing to discern cytosine methylation changes in relation to transcriptome and phenotype. Regional methylation changes were dispersed over the epiline genomes. A number of upstream-associated differentially methylated regions (DMRs) correlated with differentially expressed genes (DEGs) with a role in particular molecular functions like transmembrane transport and protein kinase activity. Targeted bisulfite sequencing confirmed epiline DMRs that anti-correlated with DEGs, identifying puta...
International Journal of Biochemistry, 1988
Plant Physiology and Biochemistry, Oct 1, 2002
At present, there is no general laboratory assay described that allows quantification of the yiel... more At present, there is no general laboratory assay described that allows quantification of the yield potential of plant lines obtained in breeding or research programmes. The only way to evaluate the performance of a plant line is by greenhouse and field trials over several years on different locations. In this paper, an in vitro physiological method is described that allows
Proceedings of the National Academy of Sciences of the United States of America, Sep 18, 2007
Archives of Physiology and Biochemistry, 1996
Springer eBooks, 1988
Phosphinotricin (PPT) is a new non-selective contact herbicide. It is an analogous of glutamate a... more Phosphinotricin (PPT) is a new non-selective contact herbicide. It is an analogous of glutamate and acts as an irreversible inhibitor of the plant glutamine synthetase. The compound is obtained by chemical synthesis (BastaR, Hoechst AG) or naturally produced by some microorganisms as part of a tripeptide antibiotic — e.g. the tripeptide bialaphos from Streptomyces hyqroscopicus (HerbiaceR, Meiji Seika Ltd).
Physiologia Plantarum, May 1, 1990
The attempts to manipulate organelle DNA of higher plants have not yet been succesfull. Although ... more The attempts to manipulate organelle DNA of higher plants have not yet been succesfull. Although some Agrobacterium mediated and direct gene transfer experi‐ments suggested that chloroplasts of Nicotiana tabacum could be transformed, these experiments could not be reproduced. New transformation techniques have emerged: laser‐injection, microinjection and high velocity microprojectiles. The biolistic ex‐periments with Chlamydomonas made it clear that organelle DNA can support introduced DNA fragments by homologous recombination. In view of these devel‐opments, we describe the parameters and new possibilities for chloroplast trans‐formation of higher plants.
Agronomy, Feb 18, 2019
Two of the major pathways involved in induced defense of plants against pathogens include the sal... more Two of the major pathways involved in induced defense of plants against pathogens include the salicylic acid (SA)-and jasmonic acid (JA)-mediated pathways that act mainly against biotrophs and necrotrophs, respectively. However, some necrotrophic pathogens, such as Botrytis cinerea, actively induce the SA pathway, resulting in cell death that allows the pathogen to proliferate in the plant. Starting from an isogenic canola (Brassica napus) line, epilines were selected with a reduced sensitivity to SA. The genes belonging to the SA pathway had an altered transcription profile in the SA-tolerant lines, when treated with SA. Besides the already known genes of the SA pathway, new SA target genes were identified, creating possibilities to better understand the plant defense mechanism against pathogens. The SA-tolerant line with the lowest SA-induced gene expression is tolerant to Botrytis cinerea. When treated with SA, this line has also a reduced histone modification (histone H3 lysine 4 trimethylation) at the genes at the start of the SA pathway.
The EMBO Journal, Jun 1, 1985
A chimeric gene consisting of the promoter region of the nopaline synthase gene (Pnos) fused to t... more A chimeric gene consisting of the promoter region of the nopaline synthase gene (Pnos) fused to the coding sequence of the chloramphenicol acetyltransferase gene (cat gene) of Tn9 was introduced by co-cultivation in tobacco protoplasts followed by selection with 10 ,g/ml chloramphenicol. The chloramphenicol-resistant plants derived from these selected calli were unable to transmit the CmR phenotype through pollen. A typically maternal inheritance pattern was observed. Southern blot analysis showed that the chimeric Pnos-cat gene was present in the chloroplasts of these resistant plants. Furthermore, the chloramphenicol acetyltransferase activity was shown to be associated with the chloroplast fraction. These observations are the first proof that the Agrobacterium Tiplasmid vectors can be used to introduce genes in chloroplasts.
Biochemical Society Transactions, Nov 1, 1996
Plant DNA Infectious Agents, 1987
Reproducible methods, allowing the introduction of defined DNA fragments in the plant nuclear gen... more Reproducible methods, allowing the introduction of defined DNA fragments in the plant nuclear genome, are presently available (see previous chapters in this volume) and are contributing significantly to the experimental analysis of the gene structure-function relationships governing regulated gene-expression in plants.
Agronomy, 2019
Two of the major pathways involved in induced defense of plants against pathogens include the sal... more Two of the major pathways involved in induced defense of plants against pathogens include the salicylic acid (SA)- and jasmonic acid (JA)-mediated pathways that act mainly against biotrophs and necrotrophs, respectively. However, some necrotrophic pathogens, such as Botrytis cinerea, actively induce the SA pathway, resulting in cell death that allows the pathogen to proliferate in the plant. Starting from an isogenic canola (Brassica napus) line, epilines were selected with a reduced sensitivity to SA. The genes belonging to the SA pathway had an altered transcription profile in the SA-tolerant lines, when treated with SA. Besides the already known genes of the SA pathway, new SA target genes were identified, creating possibilities to better understand the plant defense mechanism against pathogens. The SA-tolerant line with the lowest SA-induced gene expression is tolerant to Botrytis cinerea. When treated with SA, this line has also a reduced histone modification (histone H3 lysine...
The EMBO Journal, 1994
2Corresponding author Communicated by M.Van Montagu In Arabidopsis, mutation at PFL causes pointe... more 2Corresponding author Communicated by M.Van Montagu In Arabidopsis, mutation at PFL causes pointed first leaves, reduced fresh weight and growth retardation. We have cloned the wild-type PFL gene by T-DNA tagging, and demonstrate that it complements the mutant phenotype. PFL codes for ribosomal protein S18, based on the high homology with rat S18 and on purification of S18-equivalent peptides from plant ribosomes. pfl represents the first mutation in eukaryotic S18 proteins or their S13 prokaryotic counterparts, involved in translation initiation. Arabidopsis contains three S18 gene copies dispersed in the genetic map; they are all transcribed and code for completely identical proteins. No transcript is detected from the mutated gene, S18A. The activity of the S18A promoter is restricted to meristems, with a markedly high expression at the embryonic heart stage, and to wounding sites. This means that plants activate an extra copy of this ribosomal protein gene in tissues with cell division activity. We postulate that in meristematic tissues plants use transcriptional control to synthesize extra ribosomes to increase translational efficiency. In analogy with this, an additional, developmentally regulated gene copy might be expected for all ribosomal proteins.
Agronomy, 2018
Epigenetics offers important opportunities in breeding to improve the potential yield in a wide v... more Epigenetics offers important opportunities in breeding to improve the potential yield in a wide variety of crops. Starting from a pure breeder seed lot of a rice (Oryza sativa ssp. indica) inbred population, repeated testing for improved cellular respiration rates and energy use efficiency (EUE) over three generations identified performant epilines with distinct epigenetic signatures and with improved seed yield in field trials. Epiline DNA methylomes were characterized by genome-wide bisulfite sequencing to discern cytosine methylation changes in relation to transcriptome and phenotype. Regional methylation changes were dispersed over the epiline genomes. A number of upstream-associated differentially methylated regions (DMRs) correlated with differentially expressed genes (DEGs) with a role in particular molecular functions like transmembrane transport and protein kinase activity. Targeted bisulfite sequencing confirmed epiline DMRs that anti-correlated with DEGs, identifying puta...