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Biology subjects

Dussarrat, T.

Publications and source records attributed to Dussarrat, T..

3 recordsLinked to original sources

Convergent and divergent responses of the rhizosphere chemistry and bacterial communities to a stress gradient in the Atacama Desert.

Plants can modulate their rhizosphere chemistry, thereby influencing microbe communities. Although our understanding of rhizosphere chemistry is growing, knowledge of its responses to abiotic constraints is limited, especially in realistic ecological contexts. Here, we combined predictive metabolomics with bacterial sequencing data to investigate whether rhizosphere chemistry responded to environmental constraints and shaped bacterial communities across an elevation gradient in the Atacama Desert. We found that metabolic adjustments of rhizosphere chemistry predicted the environment of four plant species independently of year, identifying important rhizosphere metabolic biomarkers. Inter-species predictions unveiled significant biochemical convergences. Subsequently, we linked metabolic predictors to variation in the abundance of operational taxonomic units (OTUs). Chemical response influenced distinct and common bacterial families between species and vegetation belts. The annotation of chemical markers and correlated bacterial families highlighted critical biological processes such as nitrogen starvation, metal pollution and plant development and defence. Overall, this study demonstrates a unique metabolic set likely involved in improving plant resilience to harsh edaphic conditions. Besides, the results emphasise the need to integrate ecology with plant metabolome and microbiome approaches to explore plant-soil interactions and better predict their responses to climate change and consequences for ecosystem dynamics.

ecology↗

Phylogenetically diverse wild plant species use common biochemical strategies to thrive in the Atacama Desert

The best ideotypes are under mounting pressure due to increased aridity in many parts of the world. Understanding the conserved molecular mechanisms that evolve in wild plant species adapted to harsh environments is crucial in developing new strategies for sustainable agriculture. Yet our knowledge of such mechanisms in wild species is scant, particularly in extreme environments. We performed metabolic pathway reconstruction using transcriptome information from 32 Atacama plant species and phylogenetically related plant species that do not live in Atacama (Sister species). We analyzed pathway and reaction enrichment to understand the biochemical commonalities and differences of wild Atacama plant species. To gain insights into the mechanisms that ensure plant survival, we compared expressed gene isoform numbers and gene expression patterns between the annotated biochemical reactions from 32 Atacama and Sister species. We found significant biochemical convergences in primary and secondary metabolism characterized by reactions enriched in at least 50% of the Atacama species across major plant phylogenetic lineages. Analysis of the annotation indicated potential advantages against drought, salinity, high solar irradiance, and nitrogen starvation. These findings suggest that the adaptation in the Atacama Desert may result in part from shared genetic legacies governing the expression of key metabolic pathways to face harsh environmental conditions. Enriched reactions corresponded to ubiquitous compounds common to extreme and agronomic species and were congruent with our previous metabolomic analyses in these Atacama species. Hence, genes underlying these adaptive traits offer promising candidates for improving abiotic stress resilience in crop species.

plant biology↗

Influences of chemotype and parental genotype on metabolic fingerprints of tansy plants uncovered by predictive metabolomics.

Intraspecific plant chemodiversity shapes plant-environment interactions. Within species, chemotypes can be defined according to variation in dominant specialised metabolites belonging to certain classes. Different ecological functions could be assigned to these distinct chemotypes. However, the roles of other metabolic variations and the parental genotype of the chemotypes remain poorly explored. Here, we first compared the capacity of terpenoid profiles and metabolic fingerprints to distinguish five chemotypes of common tansy (Tanacetum vulgare) and depict satellite metabolic differences. Metabolic fingerprints captured higher satellite variation while preserving the ability to define chemotypes. These satellite differences might influence plant performance and interactions with the environment. Next, to characterise the influence of the maternal genotype on chemodiversity, we performed variation partitioning and generalised linear modelling. Our findings revealed that maternal genotype was a higher source of chemical variation than chemotype. Predictive metabolomics unveiled 184 markers predicting maternal genotype with 89% accuracy. These markers included, among others, phenolics, whose functions in plant-environment interactions are well established. Hence, these findings place parental genotype at the forefront of intraspecific chemodiversity. We thus recommend considering this factor when comparing the ecology of various chemotypes. Besides, the combined inclusion of inherited and satellite metabolic variation in computational models may help connecting chemodiversity and evolutionary principles.

ecology↗