Project description:Cowpea (Vigna unguiculata) is an important protein source in Sub-Saharan Africa. Optimizing resilience and productivity through genetic engineering in cowpea has been slow due in part to a lack of defined species-specific regulatory elements and difficulty testing gene function within the native system. In many plant species, Agrobacterium-mediated transient gene expression is widely used to validate constructs before investing in transgenic lines, but its implementation in legumes has been challenging. In this study, we optimized an in planta agroinfiltration assay in trifoliate cowpea leaves using a betalain reporter. To demonstrate the “intact plant” aspect of this system, we used this assay to characterize drought-inducible promoters by challenging cowpea plants with drought stress. Subsequently, to identify and broaden the pool of native promoters known in cowpea, we developed a user-friendly web application, CowPEAsy, allowing users to interrogate gene expression from our canopy-level, developmental-series RNA-Seq dataset. Finally, using CowPEAsy, we identified six promoters that showed constitutive expression across all conditions and verified these promoters with our transient system. This work provides an in vivo platform for preliminary validation of regulatory elements in cowpea and other legumes and enhances current genetic resources by identifying a suite of physiologically relevant promoters of varying strengths.
Project description:Aging and age-related neurodegeneration are among the major challenges because of the progressive increase in the number of elder people in the wold population. Nutrition, which has important long-term consequences for health, is actually considered a means to prevent diseases and to reach a healthy aging. Here we investigate the role of Vigna unguiculata beans on senescence by using Saccharomyces cerevisiae and Drosophila melanogaster as model systems. Aqueous extract, mainly containing starch, proteins and amino acids, extends chronological lifespan in yeast cells, showing a remarkable synergistic effect in combination with caloric restriction. The extension of yeast longevity requires both the anti-aging Snf1/AMPK and the pro-aging Ras2/PKA pathways. A significant marked increase of lifespan was observed also in fruit flies supplemented with the V. unguiculata extract, which is accompanied by the increased expression of FOXO, NOTCH, SIRT1 and heme oxygenase (HO) genes, already known to be required for the extension of fruit fly longevity. α-synuclein forms toxic intracellular protein inclusions in Parkinson’s disease (PD) and actually preventing α-synuclein self-assembly has become one of the most promising approaches for the treatment of this neurodegenerative disorder. Here, we report that in vitro aggregation of -synuclein, as well as its toxicity in yeast and in neuroblastoma cells, are strongly decreased in the presence of bean extract. In addition, in a Caenorhabditis elegans model of PD that expresses α-synuclein, Vigna unguiculate extract substantially reduces the number of the age-dependent degeneration of the cephalic dopaminergic neurons. Overall, our data support the role of Vigna unguiculata beans as a functional food, worth to be further explored in order to develop lead molecules for therapeutic intervention in age-related disorders.