Pierre R Fobert

McMaster University, Hamilton, Ontario, Canada

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Publications (50)213.61 Total impact

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    ABSTRACT: HIGH-LEVEL EXPRESSION OF SUGAR INDUCIBLE GENE2 (HSI2), also known as VAL1, is a B3 domain transcriptional repressor that acts redundantly with its closest relative, HSI2-LIKE1 (HSL1), to suppress the seed maturation program following germination. Mutant hsi2 hsl1 seedlings are arrested early in development and differentially express a number of abiotic stress-related genes. To test the potential requirement for HSI2 during abiotic stress, hsi2 single mutants and plants overexpressing HSI2 were subjected to simulated drought stress by withholding watering, and characterized through physiological, metabolic and gene expression studies. The hsi2 mutants demonstrated reduced wilting and maintained higher relative water content than wild-type after withholding watering, while the overexpressing lines displayed the opposite phenotype. The hsi2 mutant displayed lower constitutive and ABA-induced stomatal conductance than wild-type and accumulated lower levels of ABA metabolites and several osmolytes and osmoprotectants following water withdrawal. Microarray comparisons between wild-type and the hsi2 mutant revealed that steady-state levels of numerous stress-induced genes were up-regulated in the mutant in the absence of stress but down-regulated at visible wilting. Plants with altered levels of HSI2 responded to exogenous application of ABA and a long-lived ABA analog, but the hsi2 mutant did not show altered expression of several ABA-responsive or ABA signalling genes 4 hr after application. These results implicate HSI2 as a negative regulator of drought stress response in Arabidopsis, acting, at least in part, by regulating transpirational water loss. Metabolic and global transcript profiling comparisons of the hsi2 mutant and wild-type plants do not support a model whereby the greater drought tolerance observed in the hsi2 mutant is conferred by the accumulation of known osmolytes and osmoprotectants. Instead, data are consistent with mutants experiencing a relatively milder dehydration stress following water withdrawal.
    BMC Plant Biology 10/2013; 13(1):170. · 4.35 Impact Factor
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    ABSTRACT: DIR1 is a lipid transfer protein (LTP) postulated to complex with and/or chaperone a signal(s) to distant leaves during Systemic Acquired Resistance (SAR) in Arabidopsis. DIR1 was detected in phloem sap-enriched petiole exudates collected from wild-type leaves induced for SAR, suggesting that DIR1 gains access to the phloem for movement from the induced leaf. Occasionally the defective in induced resistance1 (dir1-1) mutant displayed a partially SAR-competent phenotype and a DIR1-sized band in protein gel blots was detected in dir1-1 exudates suggesting that a highly similar protein, DIR1-like (At5g48490), may contribute to SAR. Recombinant protein studies demonstrated that DIR1 polyclonal antibodies recognize DIR1 and DIR1-like. Homology modeling of DIR1-like using the DIR1-phospholipid crystal structure as template, provides clues as to why the dir1-1 mutant is rarely SAR-competent. The contribution of DIR1 and DIR1-like during SAR was examined using an Agrobacterium-mediated transient expression-SAR assay and an estrogen-inducible DIR1-EGFP/dir1-1 line. We provide evidence that upon SAR induction, DIR1 moves down the leaf petiole to distant leaves. Our data also suggests that DIR1-like displays a reduced capacity to move to distant leaves during SAR and this may explain why dir1-1 is occasionally SAR-competent.
    Frontiers in Plant Science 01/2013; 4:230. · 3.60 Impact Factor
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    Lipu Wang, Pierre R Fobert
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    ABSTRACT: During the plant immune response, large-scale transcriptional reprogramming is modulated by numerous transcription (co) factors. The Arabidopsis basic leucine zipper transcription factors TGA1 and TGA4, which comprise the clade I TGA factors, have been shown to positively contribute to disease resistance against virulent strains of the bacterial pathogen Pseudomonas syringae. Despite physically interacting with the key immune regulator, NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1), following elicitation with salicylic acid (SA), clade I function was shown to be largely independent of NPR1. Unlike mutants in NPR1, tga1-1 tga4-1 plants do not display reductions in steady-state levels of SA-pathway marker genes following treatment with this phenolic signaling metabolite or after challenge with virulent or avirulent P. syringae. By exploiting bacterial strains that have limited capacity to suppress Arabidopsis defence responses, the present study demonstrates that tga1-1 tga4-1 plants are compromised in basal resistance and defective in several apoplastic defence responses, including the oxidative burst of reactive oxygen species, callose deposition, as well as total and apoplastic PATHOGENESIS-RELATED 1 (PR-1) protein accumulation. Furthermore, analysis of npr1-1 and the tga1-1 tga4-1 npr1-1 triple mutant indicates that clade I TGA factors act substantially independent of NPR1 in mediating disease resistance against these strains of P. syringae. Increased sensitivity to the N-glycosylation inhibitor tunicamycin and elevated levels of endoplasmic reticulum (ER) stress marker genes encoding ER-resident chaperones in mutant seedlings suggest that loss of apoplastic defence responses is associated with aberrant protein secretion and implicate clade I TGA factors as positive regulators of one or more ER-related secretion pathways.
    PLoS ONE 01/2013; 8(9):e77378. · 3.53 Impact Factor
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    ABSTRACT: Transcriptional reprogramming during induction of salicylic acid (SA)-mediated defenses is regulated primarily by NPR1 (NONEXPRESSOR OF PATHOGENESIS-RELATED GENES 1), likely through interactions with TGA bZIP transcription factors. To ascertain the contributions of clade I TGA factors (TGA1 and TGA4) to defense responses, a tga1-1 tga4-1 double mutant was constructed and challenged with Pseudomonas syringae and Hyaloperonospora arabidopsidis. Although the mutant displayed enhanced susceptibility to virulent P. syringae, it was not compromised in systemic acquired resistance against this pathogen or resistance against avirulent H. arabidopsidis. Microarray analysis of nonelicited and SA-treated plants indicated that clade I TGA factors regulate fewer genes than NPR1. Approximately half of TGA-dependent genes were regulated by NPR1 but, in all cases, the direction of change was opposite in the two mutants. In support of the microarray data, the NPR1-independent disease resistance observed in the autoimmune resistance (R) gene mutant snc1 is partly compromised by tga1-1 tga4-1 mutations, and a triple mutant of clade I TGA factors with npr1-1 is more susceptible than either parent. These results suggest that clade I TGA factors are required for resistance against virulent pathogens and avirulent pathogens mediated by at least some R gene specificities, acting substantially through NPR1-independent pathways.
    Molecular Plant-Microbe Interactions 08/2012; 25(11):1459-68. · 4.31 Impact Factor
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    ABSTRACT: Nowadays, it is possible to collect expression levels of a set of genes from a set of biological samples during a series of time points. Such data have three dimensions: gene-sample-time (GST). Thus they are called 3D microarray gene expression data. To take advantage of the 3D data collected, and to fully understand the biological knowledge hidden in the GST data, novel subspace clustering algorithms have to be developed to effectively address the biological problem in the corresponding space. We developed a subspace clustering algorithm called Order Preserving Triclustering (OPTricluster), for 3D short time-series data mining. OPTricluster is able to identify 3D clusters with coherent evolution from a given 3D dataset using a combinatorial approach on the sample dimension, and the order preserving (OP) concept on the time dimension. The fusion of the two methodologies allows one to study similarities and differences between samples in terms of their temporal expression profile. OPTricluster has been successfully applied to four case studies: immune response in mice infected by malaria (Plasmodium chabaudi), systemic acquired resistance in Arabidopsis thaliana, similarities and differences between inner and outer cotyledon in Brassica napus during seed development, and to Brassica napus whole seed development. These studies showed that OPTricluster is robust to noise and is able to detect the similarities and differences between biological samples. Our analysis showed that OPTricluster generally outperforms other well known clustering algorithms such as the TRICLUSTER, gTRICLUSTER and K-means; it is robust to noise and can effectively mine the biological knowledge hidden in the 3D short time-series gene expression data.
    BMC Bioinformatics 04/2012; 13:54. · 3.02 Impact Factor
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    ABSTRACT: Systemic Acquired Resistance (SAR) is an induced resistance response to pathogens, characterized by the translocation of a long-distance signal from induced leaves to distant tissues to prime them for increased resistance to future infection. DEFECTIVE in INDUCED RESISTANCE 1 (DIR1) has been hypothesized to chaperone a small signaling molecule to distant tissues during SAR in Arabidopsis. DIR1 promoter:DIR1-GUS/dir1-1 lines were constructed to examine DIR1 expression. DIR1 is expressed in seedlings, flowers and ubiquitously in untreated or mock-inoculated mature leaf cells, including phloem sieve elements and companion cells. Inoculation of leaves with SAR-inducing avirulent or virulent Pseudomonas syringae pv tomato (Pst) resulted in Type III Secretion System-dependent suppression of DIR1 expression in leaf cells. Transient expression of fluorescent fusion proteins in tobacco and intercellular washing fluid experiments indicated that DIR1's ER signal sequence targets it for secretion to the cell wall. However, DIR1 expressed without a signal sequence rescued the dir1-1 SAR defect, suggesting that a cytosolic pool of DIR1 is important for the SAR response. Although expression of DIR1 decreases during SAR induction, the protein localizes to all living cell types of the vasculature, including companion cells and sieve elements, and therefore DIR1 is well situated to participate in long-distance signaling during SAR.
    BMC Plant Biology 09/2011; 11:125. · 4.35 Impact Factor
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    ABSTRACT: ROXY1 and ROXY2 are CC-type floral glutaredoxins with redundant functions in Arabidopsis (Arabidopsis thaliana) anther development. We show here that plants lacking the basic leucine-zipper transcription factors TGA9 and TGA10 have defects in male gametogenesis that are strikingly similar to those in roxy1 roxy2 mutants. In tga9 tga10 mutants, adaxial and abaxial anther lobe development is differentially affected, with early steps in anther development blocked in adaxial lobes and later steps affected in abaxial lobes. Distinct from roxy1 roxy2, microspore development in abaxial anther lobes proceeds to a later stage with the production of inviable pollen grains contained within nondehiscent anthers. Histological analysis shows multiple defects in the anther dehiscence program, including abnormal stability and lignification of the middle layer and defects in septum and stomium function. Compatible with these defects, TGA9 and TGA10 are expressed throughout early anther primordia but resolve to the middle and tapetum layers during meiosis of pollen mother cells. Several lines of evidence suggest that ROXY promotion of anther development is mediated in part by TGA9 and TGA10. First, TGA9 and TGA10 expression overlaps with ROXY1/2 during anther development. Second, TGA9/10 and ROXY1/2 operate downstream of SPOROCYTELESS/NOZZLE, where they positively regulate a common set of genes that contribute to tapetal development. Third, TGA9 and TGA10 directly interact with ROXY proteins in yeast and in plant cell nuclei. These findings suggest that activation of TGA9/10 transcription factors by ROXY-mediated modification of cysteine residues promotes anther development, thus broadening our understanding of how redox-regulated TGA factors function in plants.
    Plant physiology 11/2010; 154(3):1492-504. · 6.56 Impact Factor
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    ABSTRACT: The architecture of the Brassica napus genome is marked by its evolutionary origins. The genome of B. napus was formed from the hybridization of two closely related diploid Brassica species, both of which evolved from an hexaploid ancestor. The extensive whole genome duplication events in its near and distant past result in the allotetraploid genome of B. napus maintaining multiple copies of most genes, which predicts a highly complex and redundant transcriptome that can confound any expression analyses. A stringent assembly of 142,399 B. napus expressed sequence tags allowed the development of a well-differentiated set of reference transcripts, which were used as a foundation to assess the efficacy of available tools for identifying and distinguishing transcripts in B. napus; including microarray hybridization and 3' anchored sequence tag capture. Microarray platforms cannot distinguish transcripts derived from the two progenitors or close homologues, although observed differential expression appeared to be biased towards unique transcripts. The use of 3' capture enhanced the ability to unambiguously identify homologues within the B. napus transcriptome but was limited by tag length. The ability to comprehensively catalogue gene expression in polyploid species could be transformed by the application of cost-efficient next generation sequencing technologies that will capture millions of long sequence tags.
    Genome 11/2010; 53(11):929-38. · 1.65 Impact Factor
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    ABSTRACT: yes yes
    06/2010;
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    ABSTRACT: We studied defense mechanism of the Arabidopsis thaliana subjected to Salicylic Acid (SA) treatment for 0, 1, and 8 hours using a broader application of the frequent itemset approach. Four genotypes of the plant were used in this study, Columbia wild type, mutant npr1-3, double mutant tga1 tga4 and triple mutant tga2 tga5 tga6. We defined the major patterns of transcription regulation governing pathogen defense mechanism, thereby creating a model of the Systemic Acquired Resistance (SAR) at three time points. The temporal model describes the relationships among the regulators and defines groups of genes that are subject to similar regulation. The results obtained offered a first glimpse into the temporal pattern of the transcription regulatory network during SAR in Arabidopsis thaliana. We found that most of the genes that responded to SA challenge are in fact dependent on one or more of the NPR1 and TGA factors tested in this study.
    Computational Intelligence in Bioinformatics and Computational Biology (CIBCB), 2010 IEEE Symposium on; 05/2010
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    ABSTRACT: Vast amount of data in various forms have been accumulated through many years of functional genomic research throughout the world. It is a challenge to discover and disseminate knowledge hidden in these data. Many computational methods have been developed to solve this problem. Taking analysis of the microarray data as an example, we spent the past decade developing many data mining strategies and software tools. It appears still insufficient to cover all sources of data. In this paper, we summarize our experiences in mining microarray data by using two plant species, Brassica napus and Arabidopsis thaliana, as examples. We present several successful stories and also a few lessons learnt. The domain problems that we dealt with were the transcriptional regulation in seed development and during defense response against pathogen infection.
    Trends in Applied Intelligent Systems - 23rd International Conference on Industrial Engineering and Other Applications of Applied Intelligent Systems, IEA/AIE 2010, Cordoba, Spain, June 1-4, 2010, Proceedings, Part III; 01/2010
  • Plant Physiology. 01/2010; 154:1492-1504.
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    ABSTRACT: TGA2 and NONEXPRESSER OF PR GENES1 (NPR1) are activators of systemic acquired resistance (SAR) and of the SAR marker gene pathogenesis-related-1 (PR-1) in Arabidopsis thaliana. TGA2 is a transcriptional repressor required for basal repression of PR-1, but during SAR, TGA2 recruits NPR1 as part of an enhanceosome. Transactivation by the enhanceosome requires the NPR1 BTB/POZ domain. However, the NPR1 BTB/POZ domain does not contain an autonomous transactivation domain; thus, its molecular role within the enhanceosome remains elusive. We now show by gel filtration analyses that TGA2 binds DNA as a dimer, tetramer, or oligomer. Using in vivo plant transcription assays, we localize the repression domain of TGA2 to the N terminus and demonstrate that this domain is responsible for modulating the DNA binding activity of the oligomer both in vitro and in vivo. We confirm that the NPR1 BTB/POZ domain interacts with and negates the molecular function of the TGA2 repression domain by excluding TGA2 oligomers from cognate DNA. These data distinguish the NPR1 BTB/POZ domain from other known BTB/POZ domains and establish its molecular role in the context of the Arabidopsis PR-1 gene enhanceosome.
    The Plant Cell 11/2009; 21(11):3700-13. · 9.25 Impact Factor
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    ABSTRACT: Pathogen-induced transcriptional reprogramming of the plant genome is mediated predominantly by the cofactor NPR1 (NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1). NPR1 lacks any known DNA-binding domain and is proposed to regulate transcription through interactions with TGA transcription factors that bind to as-1-like promoter elements. Previous studies have focused on the interaction of NPR1 with subgroup I (TGA1, TGA4) or subgroup II (TGA2, TGA5, TGA6) factors. Using the yeast two-hybrid system, we showed that a member of subgroup III (TGA7) interacts with wild-type NPR1 but not with mutants in the ankyrin repeats that are important for disease resistance. Mutations in the NPR1 BTB/POZ domain also greatly reduced interaction with TGA7. NPR1 substantially increased the binding of TGA7 to cognate promoter elements in vitro, including a salicylic-acid-inducible element of the PR-1 promoter. While TGA7 interacted with all TGA factors tested, interactions were not observed between TGA2 and subgroup I factors, indicating that cross-clade interaction is not a general property of the family. Transcripts from subgroup III TGA factors were weakly inducible by salicylic acid and pathogens, but only TGA3 expression was dependent on NPR1. These results suggest that NPR1-mediated DNA binding of TGA7 could regulate the activation of defense genes.La reprogrammation transcriptionnelle du génome végétal, induite par des agents pathogènes, s'effectue surtout sous l'effet du cofacteur NPR1 (NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1). Le NPR1 ne possède aucun domaine de liaison de l'ADN et on le propose comme régulateur de transcription par des interactions avec les facteurs de transcription TGA qui s'attachent à des éléments de promoteurs ressemblant au as-1. Des études antécédentes se sont concentrées sur l'interaction du NPR1 avec les facteurs du sous-groupe I (TGA1, TGA4) ou du sous-groupe II (TGA2, TGA5, TGA6). En utilisant le système hybride double de la levure, les auteurs montrent qu'un membre du sous-groupe III (TGA7) interagit avec le NPR1 du type sauvage, mais pas avec les mutants dans les itérations de l'ankyrine qui sont importantes pour la résistance aux maladies. Des mutations dans le domaine du NPR1 BTB/POZ diminuent aussi fortement les interactions avec le TGA7. Le NPR1 augmente substantiellement in vitro la liaison du TGA7 à des éléments de promoteur connus, y compris un élément du promoteur PR-1 inductible par l’acide salicylique. Alors que le TGA7 interagit avec tous les facteurs TGA testés, on n'observe pas d'interactions entre le TGA2 et les facteurs du sous-groupe I, ce qui indique que l'interaction croisée entre clades ne constitue pas une propriété générale de la famille. Les transcriptions des facteurs TGA du sous-groupe III sont faiblement inductibles par l'acide salicylique et les agents pathogènes, mais seule l'expression du TGA3 dépend du NPR1. Ces résultats suggèrent que la liaison TGA7 à l’ADN, sous l'effet du NPR1, pourrait réguler l'activation des gènes de défense.
    Botany 06/2009; 87(6):561-570. · 1.23 Impact Factor
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    ABSTRACT: Seed oil accumulates primarily as triacylglycerol (TAG). While the biochemical pathway for TAG biosynthesis is known, its regulation remains unclear. Previous research identified microsomal diacylglycerol acyltransferase 1 (DGAT1, EC 2.3.1.20) as controlling a rate-limiting step in the TAG biosynthesis pathway. Of note, overexpression of DGAT1 results in substantial increases in oil content and seed size. To further analyze the global consequences of manipulating DGAT1 levels during seed development, a concerted transcriptome and metabolome analysis of transgenic B. napus prototypes was performed. Using a targeted Brassica cDNA microarray, about 200 genes were differentially expressed in two independent transgenic lines analyzed. Interestingly, 24-33% of the targets showing significant changes have no matching gene in Arabidopsis although these represent only 5% of the targets on the microarray. Further analysis of some of these novel transcripts indicated that several are inducible by ABA in microspore-derived embryos. Of the 200 Arabidopsis genes implicated in lipid biology present on the microarray, 36 were found to be differentially regulated in DGAT transgenic lines. Furthermore, kinetic reverse transcriptase Polymerase Chain Reaction (k-PCR) analysis revealed up-regulation of genes encoding enzymes of the Kennedy pathway involved in assembly of TAGs. Hormone profiling indicated that levels of auxins and cytokinins varied between transgenic lines and untransformed controls, while differences in the pool sizes of ABA and catabolites were only observed at later stages of development. Our results indicate that the increased TAG accumulation observed in transgenic DGAT1 plants is associated with modest transcriptional and hormonal changes during seed development that are not limited to the TAG biosynthesis pathway. These might be associated with feedback or feed-forward effects due to altered levels of DGAT1 activity. The fact that a large fraction of significant amplicons have no matching genes in Arabidopsis compromised our ability to draw concrete inferences from the data at this stage, but has led to the identification of novel genes of potential interest.
    BMC Genomics 01/2009; 9:619. · 4.40 Impact Factor
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    ABSTRACT: Developing seeds of Brassica napus contain significant levels of ABA and products of oxidation at the 7'- and 9'-methyl groups of ABA, 7'- and 9'-hydroxy ABA, as well stable products of oxidation of the 8'-methyl group, phaseic acid and dihydrophaseic acid. To probe the biological roles of the initially formed hydroxylated compounds, we have compared the effects of supplied ABA and the hydroxylated metabolites in regulating oil synthesis in microspore-derived embryos of B. napus, cv Hero that accumulate long chain fatty acids. Uptake into the embryos and metabolism of each of the hormone metabolites was studied by using deuterium labeled analogs. Supplied ABA, which was rapidly metabolized, induced expression of oleosin and fatty acid elongase genes and increased the accumulation of triacylglycerols and very long chain fatty acids. The metabolites 7'- and 9'-hydroxy ABA had similar effects, with the 9'-hydroxy ABA having even greater activity than ABA. The principal catabolite of ABA, 8'-hydroxy ABA, also had hormonal activity and led to increased oil synthesis but induced the genes weakly. These results indicate that all compounds tested could be involved in lipid synthesis in B. napus, and may have hormonal roles in other ABA-regulated processes.
    Phytochemistry 10/2008; 69(15):2678-88. · 3.35 Impact Factor
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    ABSTRACT: Plants utilize tightly regulated mechanisms to defend themselves against pathogens. Initial recognition results in activation of specific Resistance (R) proteins that trigger downstream immune responses, in which the signaling networks remain largely unknown. A point mutation in SUPPRESSOR OF NPR1 CONSTITUTIVE1 (SNC1), a RESISTANCE TO PERONOSPORA PARASITICA4 R gene homolog, renders plants constitutively resistant to virulent pathogens. Genetic suppressors of snc1 may carry mutations in genes encoding novel signaling components downstream of activated R proteins. One such suppressor was identified as a novel loss-of-function allele of ENHANCED RESPONSE TO ABSCISIC ACID1 (ERA1), which encodes the beta-subunit of protein farnesyltransferase. Protein farnesylation involves attachment of C15-prenyl residues to the carboxyl termini of specific target proteins. Mutant era1 plants display enhanced susceptibility to virulent bacterial and oomycete pathogens, implying a role for farnesylation in basal defense. In addition to its role in snc1-mediated resistance, era1 affects several other R-protein-mediated resistance responses against bacteria and oomycetes. ERA1 acts partly independent of abscisic acid and additively with the resistance regulator NON-EXPRESSOR OF PR GENES1 in the signaling network. Defects in geranylgeranyl transferase I, a protein modification similar to farnesylation, do not affect resistance responses, indicating that farnesylation is most likely specifically required in plant defense signaling. Taken together, we present a novel role for farnesyltransferase in plant-pathogen interactions, suggesting the importance of protein farnesylation, which contributes to the specificity and efficacy of signal transduction events.
    Plant physiology 08/2008; 148(1):348-57. · 6.56 Impact Factor
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    ABSTRACT: Vegetable oils have enormous potential as alternatives and replacements for fossil oil in high-value industrial applications. A major research thrust in Canada involves delivering the next generation of industrial oil profiles in the seeds of non-food crucifers. Progress in increasing the range of available fatty acids and improving the chemical homogeneity of Canadian crucifer seed oils are herein reviewed. © 2008 Crown in the Right of Canada. Published by John Wiley & Sons, Ltd
    Biofuels Bioproducts and Biorefining 04/2008; 2(3):206 - 214. · 3.77 Impact Factor
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    ABSTRACT: Brassica species represent several important crops including canola (Brassica napus). Understanding of genetic elements that contribute to seed-associated functions will impact future improvements in the canola crop. Brassica species share a very close taxonomic and molecular relationship with Arabidopsis thaliana. However, there are several subtle but distinct seed-associated agronomic characteristics that differ among the oil seed crop species. To address these, we have generated 67,535 ESTs predominately from Brassica seeds, analyzed these sequences, and identified 10,642 unigenes for the preparation of a targeted seed cDNA array. A set of 10,642 PCR primer pairs was designed and corresponding amplicons were produced for spotting, along with relevant controls. Critical quality control tests produced satisfactory results for use of this microarray in biological experiments. The microarray was also tested with specific RNA targets from embryos, germinating seeds, and leaf tissues. The hybridizations, signal intensities, and overall quality of these slides were consistent and reproducible. Additionally, there are 429 ESTs represented on the array that show no homology with any A. thaliana annotated gene or any gene in the Brassica genome databases or other plant databases; however, all of these probes hybridized to B. napus transcripts, indicating that the array also will be useful in defining expression patterns for genes so far unique to Brassica species.
    Genome 04/2008; 51(3):236-42. · 1.67 Impact Factor

Publication Stats

2k Citations
213.61 Total Impact Points

Institutions

  • 2011–2013
    • McMaster University
      • Department of Biology
      Hamilton, Ontario, Canada
  • 2007–2013
    • Saskatchewan Research Council
      Saskatoon, Saskatchewan, Canada
  • 2000–2013
    • University of Saskatchewan
      • Department of Biology
      Saskatoon, Saskatchewan, Canada
  • 2003–2009
    • Brock University
      • Department of Biological Sciences
      St. Catharines, Ontario, Canada
  • 2002–2009
    • National Research Council Canada
      • Plant Biotechnology Institute (PBI)
      Ottawa, Ontario, Canada
  • 2008
    • University of Toronto
      Toronto, Ontario, Canada
  • 1994–2000
    • John Innes Centre
      Norwich, England, United Kingdom
  • 1990–1999
    • Carleton University
      • • Department of Biology
      • • Institute of Biochemistry
      Ottawa, Ontario, Canada