Publications by authors named "GREC S"

One of the biggest challenges for a more widespread utilization of plant fibers is to better understand the different molecular factors underlying the variability in fineness and mechanical properties of both elementary and scutched fibers. Accordingly, we analyzed genome-wide transcription profiling from bast fiber bearing tissues of seven different flax varieties (4 spring, 2 winter fiber varieties and 1 winter linseed) and identified 1041 differentially expressed genes between varieties, of which 97 were related to cell wall metabolism. KEGG analysis highlighted a number of different enriched pathways.

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The mechanical and chemical properties of natural plant fibers are determined by many different factors, both intrinsic and extrinsic to the plant, during growth but also after harvest. A better understanding of how all these factors exert their effect and how they interact is necessary to be able to optimize fiber quality for use in different industries. One important factor is the post-harvest process known as retting, representing the first step in the extraction of bast fibers from the stem of species such as flax and hemp.

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Flax dew-retting is a key step in the industrial extraction of fibers from flax stems and is dependent upon the production of a battery of hydrolytic enzymes produced by micro-organisms during this process. To explore the diversity and dynamics of bacterial and fungal communities involved in this process we applied a high-throughput sequencing (HTS) DNA metabarcoding approach (16S rRNA/ITS region, Illumina Miseq) on plant and soil samples obtained over a period of 7 weeks in July and August 2014. Twenty-three bacterial and six fungal phyla were identified in soil samples and 11 bacterial and four fungal phyla in plant samples.

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Article Synopsis
  • Researchers identified 93 mutant families of flax with abnormal lignin development in their bast fibers, naming them the Linum usitatissimum lbf mutants, which offer new insights into how flax regulates lignin production.
  • The lbf1 mutant demonstrated a significant increase of 350% in lignin content in outer stem tissues with bast fibers, while inner tissues remained unchanged, indicating a targeted response in fiber cells.
  • Analyses revealed that this ectopic lignification is linked to enhanced expression of genes associated with lignin biosynthesis and oxidative processes, suggesting a complex regulatory mechanism in flax bast fiber development.
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Comparative genomics analysis unravels lineage-specific bursts of gene duplications related to the emergence of specialized pathways. The CYP76C subfamily of cytochrome P450 enzymes is specific to Brassicaceae. Two of its members were recently associated with monoterpenol metabolism.

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Background: Flax (Linum usitatissimum L.) is an economically important fiber and oil crop that has been grown for thousands of years. The genome has been recently sequenced and transcriptomics are providing information on candidate genes potentially related to agronomically-important traits.

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The geraniol-derived (seco)iridoid skeleton is a precursor for a large group of bioactive compounds with diverse therapeutic applications, including the widely used anticancer molecule vinblastine. Despite of this economic prospect, the pathway leading to iridoid biosynthesis from geraniol is still unclear. The first geraniol hydroxylation step has been reported to be catalyzed by cytochrome P450 enzymes such as CYP76B6 from Catharanthus roseus and CYP76C1 from Arabidopsis thaliana.

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A "novel" protocol is presented for easy and reliable estimation of soluble hydroxycinnamate levels in Cichorium intybus L. leaf tissue in large-scale experiments. Samples were standardized by punching 6 discs per leaf, and hydroxycinnamates were extracted by submerging the discs in 80% ethanol with 5% acetic acid for at least 48 h in the darkness at 4°C.

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Flax (Linum usitatissimum) stems contain cells showing contrasting cell wall structure: lignified in inner stem xylem tissue and hypolignified in outer stem bast fibers. We hypothesized that stem hypolignification should be associated with extensive phenolic accumulation and used metabolomics and transcriptomics to characterize these two tissues. (1)H nuclear magnetic resonance clearly distinguished inner and outer stem tissues and identified different primary and secondary metabolites, including coniferin and p-coumaryl alcohol glucoside.

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Phenolic contents of the ethyl acetate extracts prepared from floral buds and opened flowers harvested on Crataegus azarolus trees native in two localities were performed. The antioxidant activity was measured by DPPH' (2,2-diphenyl-picrylhydrazyl), ABTS+ (2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals scavenging using spectrophotometric method. The C.

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Nicotiana plumbaginifolia NpPDR1, a plasma membrane pleiotropic drug resistance-type ATP-binding cassette transporter formerly named NpABC1, has been suggested to transport the diterpene sclareol, an antifungal compound. However, direct evidence for a role of pleiotropic drug resistance transporters in the plant defense is still lacking. In situ immunolocalization and histochemical analysis using the gusA reporter gene showed that NpPDR1 was constitutively expressed in the whole root, in the leaf glandular trichomes, and in the flower petals.

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Expression of NpABC1, a gene encoding a plasma membrane ATP binding cassette (ABC) transporter in Nicotiana plumbaginifolia, is induced by sclareol, an antifungal diterpene produced at the leaf surface, as well as by sclareolide, a close analog. A genomic fragment including the 1282-bp region upstream of the NpABC1 transcription start was fused to the reporter beta-glucuronidase (gus) gene and introduced into N. tabacum BY2 cells for stable transformation.

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Three yeast genes, MIP (mitochondrial DNA polymerase) and two genes, YCF1 (yeast cadmium factor 1) and PDR5 (pleiotropic drug resistance 5), conferring multidrug resistance, were provided with the cauliflower mosaic virus 35S transcription promoter and introduced into tobacco using an Agrobacterium tumefaciens T-DNA-derived vector. Transcripts of each gene much shorter than those expected were found in the transgenic plants. RT-PCR and S1 nuclease mapping of the PDR5 and MIP transcripts demonstrated the presence of one (PDR5), or several close (MIP), cryptic polyadenylation site(s) within the coding sequence of these yeast genes.

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Eight hundred Jordanians with liver enlargement were studied: 369 (46%) were males and 431 (54%) females. Ages ranged between 13 and 85 years, with a mean of 47.4%: 766 cases demonstrated a single pathological process while 34 cases showed two or more processes.

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