Biology subjects

Ruiz, O. A.

Publications and source records attributed to Ruiz, O. A..

4 recordsLinked to original sources

bioRxiv2024

Unveiling the Virulence Mechanism of Leptosphaeria maculans in the Brassica napus Interaction: The Key Role of Sirodesmin PL in Cell Death Induction

Leptosphaeria maculans is the causal agent of blackleg disease in Brassica napus, leading to substantial yield losses. Sirodesmin PL, the principal toxin produced by L. maculans, has been implicated in the infective process in plants. However, the precise molecular and physiological mechanisms governing its effects remain elusive. This study investigates the changes induced by Sirodesmin PL at the transcriptomic, physiological, and morphological levels in B. napus cotyledons. Sirodesmin PL treatment upregulates genes associated with plant defense processes, including response to chitin, sulfur compound biosynthesis, toxin metabolism, oxidative stress response, and jasmonic acid/ethylene synthesis and signaling. Validation of these transcriptomic changes is evidenced by several typical defense response processes, such as the accumulation of reactive oxygen species (ROS) and callose deposition. Concomitantly, oxidized Sirodesmin PL induces concentration- and exposure duration-dependent cell death. This cellular death is likely attributed to diminished activity of photosystem II and a reduction in the number of chloroplasts per cell. In agreement, a down-regulation of genes associated with the photosynthesis process is observed following Sirodesmin PL treatment. Thus, it is plausible that L. maculans exploits Sirodesmin PL as a virulence factor to instigate cell death in B. napus during its necrotrophic stage, favoring the infective process. HighlightSirodesmin PL, the principal toxin produced by Leptosphaeria maculans, induces cell death and defense mechanisms in Brassica napus, disrupting photosynthesis and facilitating the infective process

plant biology↗

bioRxiv2020

Genetic structure of Photosystem II functionality in rice unraveled by GWAS analysis

Rice production is a particularly important crop for the half-world population. Therefore, knowledge about which genes are implicated in the functionality of the Photosystem II, that are still poorly explored could collaborate in the assisted selection of rice improving. In the present study, we applied Genome wide Association Studies of PSII chlorophyll fluorescence under two contrasting environmental conditions in 283 rice accessions highly diverse. A total of 110 significant association SNP-phenotype were observed, and 69 quantitative trait loci identified with a total of 157 genes, of which 38 were highly significant, mapped spread out through rice genome. These underlying regions are enriched in genes related to biotic and abiotic stresses, transcription factors, Calvin cycle, senescence, and grain characters. The correlations analyses PSII chlorophyll fluorescence parameters and some panicle characteristics found here suggest the possibility of developing molecular markers to assist the breeding programs that improve photosynthesis and yield in rice. HighlightThe genetic structure of the Photosystem II functionality in rice was studied by using genome-wide association through chlorophyll fluorescence.

plant biology↗

bioRxiv2020

Molecular characterization of a novel cytorhabdovirus with a unique genomic organization infecting yerba mate (Ilex paraguariensis) in Argentina

The genome of a novel rhabdovirus was detected in yerba mate (Ilex paraguariensis St. Hil.). The newly identified virus, tentatively named yerba mate virus A (YmVA), has a genome of 14,961 nucleotides. Notably, eight open reading frames were identified in the antigenomic orientation of the negative-sense, single-stranded viral RNA, including two novel accessory genes, in the order 3-N-P-3-4-M-G-L-8-5. Sequence identity of the encoded proteins as well as phylogenetic analysis suggest that YmVA is a new member of the genus Cytorhabdovirus, family Rhabdoviridae. YmVA unique genomic organization and phylogenetic relationships indicate that this virus likely represents a distinct evolutionary lineage within the cytorhabdoviruses.

microbiology↗

bioRxiv2019

The fungal endophyte Fusarium solani provokes differential effects on the energy balance of two Lotus species

Background and aimsThe interactions established between plants and endophytic fungi span a continuum from beneficial to pathogenic associations. The aim of this work was to explore the mechanisms underlying the potentially beneficial effects provoked by a fungal strain in legume species of the genus Lotus.\n\nMethodsThe ability to solubilise phosphorous was evaluated in nine fungal strains isolated from roots of L. tenuis. A selected strain was further assessed for its ability to colonize plant roots in different Lotus species. The effects of the two interactions were assessed by analysis of the photosynthesis, sugar amount, and macronutrient status of leaves and roots.\n\nResultsA fungal isolate identified as Fusarium solani shows the highest phosphate-solubilisation activity and grows endophytically in roots of L. japonicus and L. tenuis. Fungal invasion enhances plant growth in L. japonicus but provokes a contrasting effect in L. tenuis. Photosynthesis, sugars and K content showed a differential effect in both plant species.\n\nConclusionsOur results indicate neither of the plant species evaluated in this work were significantly stressed by F. solani. Thus, the differential responses observed are due to distinct mechanisms involving photosynthesis, potassium homeostasis, and carbohydrate metabolism that are employed by plants to maintain fitness during the endophytic interaction.

microbiology↗