Project description:As mammals evolved exposed to particular diets, naturally abundant compounds may have become part of the set of environmental co-determinants that shaped brain structure and function. Here we investigated whether bioactive factors found in apples directly affect hippocampal neural stem cells and promote neurogenesis in the adult. Whereas the consumption of apple juice per se neither altered adult hippocampal neurogenesis nor improved learning and memory, we did find specific direct effects of apple-derived factors on neural stem cell survival and differentiation. Our results revealed that quercetin, the most abundant flavanol in apple peel, was anti-proliferative at high concentrations but acted pro-neurogenically at low concentrations. This was confirmed in vivo, with intraperitoneally-delivered quercetin promoting survival and neuronal differentiation, without affecting proliferation, likely via the PI3 kinase-Akt and Nrf2-Keap1 pathways, respectively. Using a bio-assay-guided fractionation approach with high-resolution collision induced dissociation mass spectroscopy, we also identified additional pro-neurogenic compounds in apple flesh that were not related to flavonoids. In particular, we found that 3,5-dihydroxybenzoic acid, a weak agonist to the lactate receptor, significantly increased both in vitro and in vivo neural precursor cell proliferation and neurogenesis. Altogether, this work shows that both flavonoids and 3,5-dihydroxybenzoic acid are pro-neurogenic, not only by activating precursor cell proliferation but also through promoting cell cycle exit, cellular survival, and neuronal differentiation.
Project description:As mammals evolved with exposure to particular diets, naturally abundant compounds may have become part of the set of environmental co-determinants that shaped brain structure and function. Here we investigated whether bioactive factors found in apples directly affect hippocampal neurogenesis in the adult mouse. We found that quercetin, the most abundant flavanol in apple peel, was anti-proliferative at high concentrations but pro-neurogenic at low concentrations. This was confirmed in vivo, with intraperitoneally delivered quercetin promoting survival and neuronal differentiation, without affecting proliferation. Using a bioassay-guided fractionation approach we also identified additional pro-neurogenic compounds in apple flesh that were not related to flavonoids. We found that 3,5-dihydroxybenzoic acid significantly increased neural precursor cell proliferation and neurogenesis. This work shows that both flavonoids and 3,5-dihydroxybenzoic acid are pro-neurogenic, not only by activating precursor cell proliferation but also by promoting cell-cycle exit, cellular survival, and neuronal differentiation.
Project description:The quality of the pepper fruit is significantly influenced by the properties of its surface such as color, glossiness and texture. The fruit surface is composed of a peel containing several layers including the cuticle, epidermis and the hypodermis. The peel acts as a protective barrier against biotic and abiotic stresses and is the most critical tissue affecting water loss during post harvest storage. The peel is composed of an outer epidermis with thick waxy (lipid) cuticle and few cell layers of thick-walled hypodermal cells. Despite its agronomic importance and due to the fact that the majority of studies in fruits have been conducted using flesh and peel tissues as a whole, the biochemical and genetic bases of variation in peel properties are largely unknown. In this proposal we aim to determine peel-specific gene expression in pepper by micro array hybridizations of peel and flesh RNA extracted at different developmental stages of the fruit. The cultivar Celica (Capsicum annuum) that has a large blocky fruit will be used for studying gene expression in the peel and flesh. Plants were grown in the greenhouse during the spring of 2006. Fruits were harvested at three developmental stages: young- 10 days after anthesis, mature green- 30 days after anthesis and ripe red- 45 days after anthesis. These stages were chosen because each represents a distinct phase in fruit development. At each stage, a biological replicate consists of bulked tissue from 3 fruits from each of 3 plants (a total of 9 fruits). We have a total of 4 biological replicates. For each fruit, the peel was separated from the flesh by manual dissection using thin forceps and scalpel blade. Peel and flesh samples were immediately frozen in liquid nitrogen and stored at -800C until RNA extraction. Total RNA was extracted using the GenElute Mammalian Total RNA Miniprep kit (Sigma). Keywords: Reference design
Project description:The quality of the pepper fruit is significantly influenced by the properties of its surface such as color, glossiness and texture. The fruit surface is composed of a peel containing several layers including the cuticle, epidermis and the hypodermis. The peel acts as a protective barrier against biotic and abiotic stresses and is the most critical tissue affecting water loss during post harvest storage. The peel is composed of an outer epidermis with thick waxy (lipid) cuticle and few cell layers of thick-walled hypodermal cells. Despite its agronomic importance and due to the fact that the majority of studies in fruits have been conducted using flesh and peel tissues as a whole, the biochemical and genetic bases of variation in peel properties are largely unknown. In this proposal we aim to determine peel-specific gene expression in pepper by micro array hybridizations of peel and flesh RNA extracted at different developmental stages of the fruit. The cultivar Celica (Capsicum annuum) that has a large blocky fruit will be used for studying gene expression in the peel and flesh. Plants were grown in the greenhouse during the spring of 2006. Fruits were harvested at three developmental stages: young- 10 days after anthesis, mature green- 30 days after anthesis and ripe red- 45 days after anthesis. These stages were chosen because each represents a distinct phase in fruit development. At each stage, a biological replicate consists of bulked tissue from 3 fruits from each of 3 plants (a total of 9 fruits). We have a total of 4 biological replicates. For each fruit, the peel was separated from the flesh by manual dissection using thin forceps and scalpel blade. Peel and flesh samples were immediately frozen in liquid nitrogen and stored at -800C until RNA extraction. Total RNA was extracted using the GenElute Mammalian Total RNA Miniprep kit (Sigma). Keywords: Reference design 12 hybs total
Project description:To functionally characterise flesh pigmentation pattern, we performed methylation analysis between RF and WF mesocarps. The transition step between fully red fruits and heterogeneously pigmented fruit were targeted during fruit development (84 Days After Full Bloom - DAFB).
Project description:To functionally characterise flesh pigmentation pattern, we performed transcriptomic comparisons between RF and WF mesocarps. The transition step between fully red fruits and heterogeneously pigmented fruit were targeted during fruit development (84 Days After Full Bloom - DAFB).
Project description:Apple (Malus domestica Borkh) is an important fruit crop cultivated in a broad range of environmental conditions. Apple fruit, and specifically peel tissue, ripening is a physiological process whose molecular regulatory networks response to different environments are still not sufficiently investigated. In this study, the influence of low (20 m) and high (750 m) altitude environmental conditions in peel tissue was assessed by physiological measurements combined with global metabolite and protein expression profiling during apple fruit development and ripening. Although apple fruit ripening was unaffected by the different environmental conditions, however several key color parameters, such as redness and the color percentage index, were induced by high altitude. Consistent with this, increased level of anthocyanin and other phenolic compounds, including cyanidin-3-O-galactoside, quercetin-3-O-rhamnoside, quercetin-3-O-rutinoside and chlorogenic acid were identified in apple peel at high altitude. Also, high altitude environment, particularly, at the ripening period, up-accumulated various carbohydrates (eg., arabinose, xylose and sucrose) while repressed glutamic acid and several related proteins such as glycine hydroxymethyltransferase and glutamate–glyoxylate aminotransferase. Other processes affected by high altitude concerned the TCA cycle, the synthesis of oxidative/defense enzymes, and the accumulation of photosynthetic proteins. Finally, we constructed a metabolite-protein network depicting the impact of altitude on peel ripening. These data provide insights into physiological processes linked to apple peel ripening across different climatic conditions and will assist in efforts to improve apple fruit appeal and quality.
Project description:Apple (Malus domestica Borkh) is an important fruit crop cultivated in a broad range of environmental conditions. Apple fruit, and specifically peel tissue, ripening is a physiological process whose molecular regulatory networks response to different environments are still not sufficiently investigated. In this study, the influence of low (20 m) and high (750 m) altitude environmental conditions in peel tissue was assessed by physiological measurements combined with global metabolite and protein expression profiling during apple fruit development and ripening. Although apple fruit ripening was unaffected by the different environmental conditions, however several key color parameters, such as redness and the color percentage index, were induced by high altitude. Consistent with this, increased level of anthocyanin and other phenolic compounds, including cyanidin-3-O-galactoside, quercetin-3-O-rhamnoside, quercetin-3-O-rutinoside and chlorogenic acid were identified in apple peel at high altitude. Also, high altitude environment, particularly, at the ripening period, up-accumulated various carbohydrates (eg., arabinose, xylose and sucrose) while repressed glutamic acid and several related proteins such as glycine hydroxymethyltransferase and glutamate���glyoxylate aminotransferase. Other processes affected by high altitude concerned the TCA cycle, the synthesis of oxidative/defense enzymes, and the accumulation of photosynthetic proteins. Finally, we constructed a metabolite-protein network depicting the impact of altitude on peel ripening. These data provide insights into physiological processes linked to apple peel ripening across different climatic conditions and will assist in efforts to improve apple fruit appeal and quality.
Project description:Health benefits of apple polyphenols for different chronic diseases are postulated. To exert bioactive properties, absorption into the body is required (bioavailability), which is strongly influenced by matrix release (bioaccessibility). For seven apple varieties, in vitro experiments with simulated saliva fluid (SSF) and ex vivo digestion with centrifuged human saliva were conducted. Polyphenol characterization (high-performance liquid chromatography-tandem mass spectrometry) and quantification (high performance liquid chromatography-diode array detection) was related to an aqueous methanolic extraction. A polyphenol release of 63-82% from flesh and 42-58% from peel was estimated. While hydroxycinnamic acid derivatives were released in total, a significant retention was observed for flavanes and flavones. In particular, procyanidins were retained with increasing molecular weight. The data reveal a considerable polyphenol release during the oral digestion; however, differences among the varieties as well as flesh and peel were obvious. Due to negligible differences between both digestion media, the data supported the use of SSF instead of human saliva in further experiments.
Project description:Purpose:The red coloration of apple (Malus × domestica Borkh.) is due to the accumulation of anthocyanins in the fruit peel. Light is essential for anthocyanin biosynthesis in apple.Apple peel can quickly turn red under light conditions after unbagging. Therefore, the implementation of transcriptome sequencing to find genes that promote anthocyanin accumulation in response to light signals is necessary to clarify the mechanism of light-induced anthocyanin accumulation in apple peel.