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Arge, L. W. P.

Publications and source records attributed to Arge, L. W. P..

3 recordsLinked to original sources

SlAN1 is a limiting factor for the light-dependent anthocyanin accumulation in fruit tissues of purple tomato

Anthocyanins are specialized plant metabolites with significant dietary value due to their anti-inflammatory properties. Research indicates that dietary intake of these phenolic compounds contributes to preventing various chronic diseases. As the most consumed vegetable worldwide, tomato (Solanum lycopersicum) is an excellent candidate for anthocyanin-enrichment strategies. In tomato, activation of anthocyanin biosynthesis is light-dependent, but this mechanism has yet to be entirely characterized. We investigated the role of light in anthocyanin biosynthesis in fruits of the purple tomato, which is a near-isogenic line (NIL) derived from wild accessions into cv. Micro-Tom (MT). MT-Aft/atv/hp2 starts accumulating anthocyanin early during fruit development but is restricted to the peel (exocarp and epicarp). Manipulating light incidence in different fruit tissues determined that the absence of anthocyanin accumulation in the flesh results from the sun-blocking effect of the cyanic epicarp on the mesocarp, thus preventing light from penetrating deeper into the fruit. Transcriptional analyses of the fruit peel and flesh revealed that the bHLH transcription factor SlAN1 (Solyc09g065100) is the limiting factor for light-dependent anthocyanin accumulation in both tissues. This research enhances our comprehension of the genetic and environmental regulation of anthocyanin accumulation in fruit tissues, offering valuable insights into plant breeding for human nutrition. HighlightThe expression of the SlAN1 gene is activated in response to light signals, and it is the limiting factor for anthocyanin pigmentation in tomato fruit tissues.

plant biology↗

Uncovering the transcriptional molecular dynamics of shelf life extension and system acquired resistance induction to Fusarium pallidoroseum in melon fruits by the use of pulsed-light

Melon is a globally commercialized fruit, and Fusarium rot disease poses a significant threat to post-harvest losses. The conventional use of fungicides raises concerns about chemical residues, prompting exploration into alternative technologies such as Pulsed Light (PL). While PL has been effective in controlling infections in various fruits and vegetables, the precise physiological responses and molecular mechanisms in melon fruits remain incompletely understood. In this study, melon fruits infected with the Fusarium pallidoroseum were treated with different doses of PL (0, 6, 9, and 12 J cm-2), and the impact on both fungal control and fruit shelf life extension was investigated. The 9 J cm-2 dose emerged as the most effective in controlling fungal growth without causing damage, inducing beneficial responses. This optimal PL dose upregulated genes in the lignan biosynthesis pathway and the infection upregulated genes involved with systemic acquired resistance, triggered by the pipecolic acid. In this way, the PL treatment and the infection trigger a double mechanism of resistance in melon fruits. A second and third experiment focused on evaluating the extension of melon fruit shelf life and the safe manipulation window post-PL treatment. The results revealed an average shelf life extension of six days and a safe manipulation period of 24 hours. The extension in shelf life was associated with a deviation in information flux from the ethylene biosynthesis to upregulation of the polyamine biosynthesis pathway, which produces nitric oxide, a product that can inhibit ethylene biosynthesis and its action. Furthermore, the observed 24-hour safety period against fungal infection post-PL treatment was characterized as a memory response resistance caused by the upregulation of lignan biosynthesis, which is a potential and efficient alternative to chemical products like fungicides. Overall, this study provides insights into the transcriptional molecular mechanisms through which PL promotes systemic acquired resistance and extends the shelf life of melon fruits.

molecular biology↗

Integrative Analysis of Sorghum Bicolor Green Prop Roots Under Elevated CO2 and Water Deficit Conditions

Elevated CO2 (E[CO2]) improves the biomass and yield when combined with water-stress in C4 plants. Although several studies described the molecular response of the C4 plant Sorghum bicolor during drought exposure, none reported its combinatorial effect with E[CO2] in the roots. We decided to perform a molecular analysis using green prop roots, the portion of the radicular system photosynthetically active and more sensible to drought. Whole-transcriptome analysis identified 394 up- and 1,471 down-regulated genes. Among the E[CO2] induced pathways, photosynthesis stood out. Carbon fixation, phenylpropanoid, phenolic compounds, and fatty acid biosynthesis-related pathways were repressed. Protein family analysis showed induction of chlorophyll a-b binding protein family, and repression of glutathione-related enzymes. Protein-protein interaction networks exhibited well-defined clusters, including genes related to cell organization and biogenesis, oxi-reduction process, and photosynthesis being induced. The findings suggest that the E[CO2] mitigates the water deficit by antioxidant and osmoregulation activity, as well as by accumulation of sugar-alcohols in the green prop roots, which may be responsible by the increase in biomass together with the cell proliferation. The higher carbon uptake explains the increase in photosynthetic and primary metabolism activities. Our data revealed that green prop roots present an intriguing metabolism under water deficit and E[CO2], showing its crucial role in the drought tolerance acquisition in a predicted future global atmosphere.

molecular biology↗