Biology subjects

El Amrani, A.

Publications and source records attributed to El Amrani, A..

3 recordsLinked to original sources

bioRxiv2025

Hijacking host microPEP: pathogens modulate the microRNA-microPEP loop to promote infection

The partners of an ecological association tend to copy the biological system of their hosts. We hypothesized that microorganisms, particularly pathogens, have acquired the ability to express short peptides (pathoPEPs) homologous to host microPEPs (miPEPs) thus modulating the expression of the corresponding host microRNA (miRNA) and the function of miRNA-targeted genes. The pathosystem involving interactions between Brassica napus and its pathogen Plasmodiophora brassicae was studied. Using in silico analysis and ribosomal profiling, we identified three putative pathoPEPs produced by P. brassicae and their targeted plant miRNA genes. A link between the level of infection of B. napus by P. brassicae and the expression of pathoPEPs and their targeted miRNA genes was found, with the expression of the latter two being inversely related. Finally, we identified differential expression and translation of genes predicted to be targets of pathoPEP-regulated miRNAs. These genes, involved in auxin pathway, immune defense, root architecture or carbohydrate metabolism, are thought to enable P. brassicae, through its pathoPEPs, to hijack plants metabolic pathways (hormonal pathways, sugar synthesis, root morphology), thereby facilitating its invasion. Using computational in silico approaches, the involvement of miPEPs from plant pathogens as a host post-transcriptional regulatory pathway is described herein for the first time.

plant biology↗

bioRxiv2022

Wide genome transcription and metabolome profiles reprogrammed by sucrose under xenobiotic constraints

Plants have developed strategies to adapt quickly to environmental changes. However, the regulation of these adaptive responses and coordination of signals network remains poorly understood for many environmental constraints. Indeed, signalling molecules play a central role in environmental stimuli and may coordinate plants development under environmental cues. Sucrose is the major transport carbohydrate in higher plants, in addition to its metabolic role; recent investigations suggested that sucrose impact the plasticity of plant development by controlling gene expression. Sucrose was also suggested as a ROS scavenger and as a signalling molecule. In this paper we showed that sucrose mitigated phenanthrene induced stress. Since, exogenous sucrose allowed growth and chlorophyll accumulation in the presence of high phenanthrene concentrations, whereas Arabidopsis development was blocked and seedlings were unable to accumulate chlorophyll in the presence of phenanthrene solely. To decipher the earlier molecular changes involved in sucrose tolerance to phenanthrene, wide transcriptional genes analysis and targeted metabolic profiling were carried out. We showed that sucrose driving plant response was associated with a deep reconfiguration of both genes expression and metabolites accumulation during the first hours of treatment, suggesting that sucrose, allowed plants to sustain the primary metabolism and to overcome the phenanthrene induced injuries.

ecology↗

bioRxiv2019

Recent hybridization and allopolyploidy reprogrammed Spartina microRNA expression under xenobiotic induced stress.

Xenobiotic detoxification is a common trait of all living organisms, necessary for developmental plasticity and stress tolerance. The gene set involved in this biological process is dubbed the xenome (i.e. involved in drug metabolism in mammals, degradation of allelochemicals and environmental pollutants by bacteria and plant communities). Recently, we found that allopolyploidy increased tolerance to xenobiotics (phenanthrene) in Spartina. To decipher the molecular mechanisms underlying this process, we examined how interspecific hybridization and genome doubling impact miRNAs expression under xenobiotic induced stress. In this work we used a deep sequencing approach, and analyzed the parental species S. alterniflora and S. maritima, their F1 hybrid S. x townsendii and the allopolyploid S. anglica under phenanthrene exposure. We found that hybridization and genome doubling reprogrammed a myriad of miRNAs under phenanthrene-induced stress. Hence, to identify the master miRNAs involved in phenanthrene tolerance, we performed experimental functional validation of phenanthrene-responsive Spar-miRNAs using Arabidopsis T-DNA mutant lines inserted in homologous MIR genes, 39 knock out T-DNA Arabidopsis mutants, tagged in the most conserved miRNAs genes in vascular plants were screened. Development of MIR159 and MIR156 mutants was significantly affected under phenanthrene-induced stress. Subsequently, we performed in planta experimental validation to confirm the interaction between these miRNAs and their targets. These analyses suggest that MIR159 and MIR156 regulatory modules were targeted to induce the xenome relaxation and impact developmental plasticity responses in phylogenetically distant species under xenobiotic-induced stress. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=111 SRC="FIGDIR/small/875138v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@9f620borg.highwire.dtl.DTLVardef@1ddd2f5org.highwire.dtl.DTLVardef@4501f1org.highwire.dtl.DTLVardef@82962d_HPS_FORMAT_FIGEXP M_FIG Graphical abstract C_FIG

evolutionary biology↗