Year: 2025
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide The grape berry mesocarp experiences key physiological changes during ripening, often including mesocarp cell death (MCD). We hypothesized that MCD does not occur in the Niagara Rosada (NR) variety but rather a downregulation of respiratory enzymes during the early loss of mesocarp cell vitality, with membrane integrity preserved. Using label-free proteomics, enzymatic activity assays, and outer mesocarp imaging, we observed intact cytoplasmic membranes, alongside with reduced mitochondrial cristae density, malate dehydrogenase, and succinate dehydrogenase activities. Proteomic analysis revealed 956 differentially accumulated proteins, with most downregulated at ripening. However, several glycolytic enzymes remained abundant at ripening, suggesting maintenance of respiratory activity despite mesocarp physiological changes, such as stress-induced and senescence-related proteins that were upregulated at veraison. We further hypothesized that gluconeogenesis originated from malate operates in the mesocarp and that sucrose futile cycles may play a crucial role in carbohydrate storage and unloading. Therefore, we suggest that the premature loss of mesocarp vitality in NR is not linked to cell death but rather a senescence adaptation.
Institution: State University of Norte Fluminense
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: hybrid
Estimated APC paid: $4,500
Awards: G3690646728, G8261118652
OpenAlex ID: W4415124157