Food-related Traits Research Articles

Characterizing the Protein Isoforms of foraging (for), the PKGI Ortholog in Drosophila melanogaster.

The foraging (for) gene of Drosophila melanogaster encodes a cGMP-dependent protein kinase (PKG), which is a major effector of the cGMP signaling pathway involved in the regulation of behaviour and metabolic traits. Despite being well studied at the transcript level, little is known about the for gene at the protein level. Here, we provide a detailed characterization of the for gene protein (FOR) products and present new tools for their study, including five isoform-specific antibodies and a transgenic strain that carries an HA-labelled for allele (forBAC::HA). Our results showed that multiple FOR isoforms were expressed in the larval and adult stages of D. melanogaster and that the majority of whole-body FOR expression arises from three (P1, P1α, and P3) of eight putative protein isoforms. We found that FOR expression differed between the larval and adult stages and between the dissected larval organs we analyzed, which included the central nervous system (CNS), fat body, carcass, and intestine. Moreover, we showed that the FOR expression differed between two allelic variants of the for gene, namely, fors (sitter) and forR (rover), that are known to differ in many food-related traits. Together, our in vivo identification of FOR isoforms and the existence of temporal, spatial, and genetic differences in their expression lay the groundwork for determining their functional significance.

Effect of Genotype and Environment on Food-Related Traits of Organic Winter Naked Barleys.

This study aimed to understand how genetics and environment influence organic winter naked barley composition and functionality, and to identify traits that might effectively categorize basic physicochemical functionality of food barley. Across three years, two locations, and 15 genotypes, genotype significantly influenced all 10 food-related traits and was the dominant influence for three. Location significantly influenced eight traits and was dominant for three. Year significantly influenced all traits but was dominant only for one. Of the interactions location * year was the most influential and was the dominant effect for two traits. For all interaction terms where genotype was a component, the effect sizes were either small or non-significant suggesting that even with low leverage traits there is the potential for genetic gain by observing trait rankings across environments. Principal component analysis identified six traits that could serve to categorize basic physicochemical functionality of food barley. These were grain protein content, beta-glucan content, flour-water batter flow, water solvent retention capacity, time to peak viscosity of cooked flour, and hardness of cooked intact grains.

Variation in Pea (Pisum sativum L.) Seed Quality Traits Defined by Physicochemical Functional Properties.

Pea is one of the most produced and consumed pulse crops around the world. The study of genetic variability within pea germplasm is an important tool to identify outstanding accessions with optimal functional and nutritional qualities. In the present study, a collection of 105 pea accessions was analysed for physicochemical properties, pasting viscosity, and basic composition parameters. While pasting viscosities were negatively correlated to hydration capacity, cooking time, and basic composition, a positive correlation was found between the hydration capacity and the basic composition parameters. Basic composition (protein, fibre, fat, and resistant starch) parameters were further evaluated regarding seed trait morphology, namely, seed shape, colour, and surface. Allelic characterisation at the r and rb genetic loci was performed in a subgroup of 32 accessions (3 phenotyped as smooth and 29 as rough seeded), revealing that none of the initially classified rough-seeded accessions were rb mutants, 19 were r mutants, and 13 were neither r nor rb. Despite their initial phenotypic classification, the 13 accessions genetically classified as smooth behaved differently (p < 0.05) to the 19 r mutants in terms of physicochemical properties, pasting viscosity, and basic composition parameters. Using multivariate analysis of the most discriminatory parameters for the food-related traits studied, the best-performing accessions at functional and nutritional levels were identified for future plant breeding to improve field pea production and consumption.

Toward a new scale to measure consumers’ “need for uniqueness” in foods and beverages: The 31-item FBNFU scale

We developed a new Food and Beverage Need for Uniqueness (FBNFU) scale to measure a personality construct postulated to underlie consumers’ predilection for unique foods and beverages. This 31-item scale was constructed to parallel a multifactorial scale used in psychology to measure the general construct of consumers’ need for uniqueness (CNFU) (Tian, Bearden, & Hunter, 2001). The FBNFU and general CNFU scales were internet-tested with 576 respondents in the US and China. The FBNFU scale had high internal consistency and a similar mean and distribution of scores as the CNFU scale in both countries. Convergent and discriminant validity of the FBNFU scale was demonstrated through comparisons with other consumer scales of need for uniqueness and food-related traits. The predictive validity of the FBNFU was assessed in two central location tests with 618 New Zealand consumers to assess whether high vs. low FBNFU consumers differ in their perceptual, hedonic, cognitive, emotional, or conative responses to food names of varying novelty/uniqueness. The FBNFU scale had high predictive validity for assessing consumer responses. High FBNFU respondents perceived novel/unique food names as less different in novelty/uniqueness and higher in expected liking, positive emotions, willingness to eat and appropriateness for use in a wide variety of situations than low FBNFU respondents. The new FBNFU scale can be used in conjunction with other trait measures (e.g., neophobia, variety seeking, food involvement) to better understand the varied factors that underlie consumer behaviour toward foods and beverages.

G1359A Variant of the Cannabinoid Receptor Gene (rs1049353) and Obesity-Related Traits and Related Endophenotypes: A Meta-Analysis

Background: This study aimed to investigate the comparison of G1359A variant of cannabinoid receptor gene (rs1049353) with obesity-related traits including body mass index (BMI), fat mass (FM), fat-free mass (FFM), food-related traits, and leptin among healthy and non-healthy adults. Methods: We searched PubMed, Cochrane, Scopus, Web of Science, and EMBASE until December 2016 for observational studies assessing each of the anthropometric measurements, food-related traits, and leptin of 1359 G/A polymorphism of CNR1 gene. A total of 22 studies were included in the meta-analysis comparing mean and SD differences of the anthropometric measurements, leptin, and dietary intake between GA/AA and GG genotypes. Results: The results showed that subjects with GA/AA genotype had significantly lower BMI (weighted mean difference = –0.59 kg/m², p < 0.001) compared to those with the GG genotype. Dietary intake of fat, carbohydrate, and protein as well as serum levels of leptin was not significantly different between GA/AA and GG genotypes. Conclusion: It was revealed that subjects with mutant polymorphism (GA/AA) of CNR1, compared to the wild-type group (GG), had lower BMI (although there was unexplained heterogeneity).

Aggressive behaviours, food deprivation and the foraging gene.

A pleiotropic gene governs multiple traits, which might constrain the evolution of complexity due to conflicting selection on these traits. However, if the pleiotropic effect is modular, then this can facilitate synergistic responses to selection on functionally related traits, thereby leveraging the evolution of complexity. To understand the evolutionary consequence of pleiotropy, the relation among functionally different traits governed by the same gene is key. We examined a pleiotropic function of the foraging (for) gene with its rover and sitter allelic variants in fruit fly, Drosophila melanogaster. We measured for's effect on adult male aggressive behaviours and whether this effect was shaped by for's known role in food-related traits. Rover exhibited higher levels of offensive behaviour than sitters and s2, a sitter-like mutant on rover genetic background. With a Markov chain model, we estimated the rate of aggression escalation, and found that the rover pattern of aggressive escalation more rapidly intensified fights. Subsequent analysis revealed that this was not caused by for's effect on food-related traits, suggesting that for might directly regulate aggressive behaviours. Food deprivation did not elevate aggression, but reduced intermediate-level aggressive behaviours. Aggression and other foraging-related behaviour might comprise a synergistic trait module underlaid by this pleiotropic gene.

Temporal-Spatial Dynamics in Orthoptera in Relation to Nutrient Availability and Plant Species Richness

Nutrient availability in ecosystems has increased dramatically over the last century. Excess reactive nitrogen deposition is known to negatively impact plant communities, e.g. by changing species composition, biomass and vegetation structure. In contrast, little is known on how such impacts propagate to higher trophic levels. To evaluate how nitrogen deposition affects plants and herbivore communities through time, we used extensive databases of spatially explicit historical records of Dutch plant species and Orthoptera (grasshoppers and crickets), a group of animals that are particularly susceptible to changes in the C:N ratio of their resources. We use robust methods that deal with the unstandardized nature of historical databases to test whether nitrogen deposition levels and plant richness changes influence the patterns of richness change of Orthoptera, taking into account Orthoptera species functional traits. Our findings show that effects indeed also propagate to higher trophic levels. Differences in functional traits affected the temporal-spatial dynamics of assemblages of Orthoptera. While nitrogen deposition affected plant diversity, contrary to our expectations, we could not find a strong significant effect of food related traits. However we found that species with low habitat specificity, limited dispersal capacity and egg deposition in the soil were more negativly affected by nitrogen deposition levels. Despite the lack of significant effect of plant richness or food related traits on Orthoptera, the negative effects of nitrogen detected within certain trait groups (e.g. groups with limited disperse ability) could be related to subtle changes in plant abundance and plant quality. Our results, however, suggest that the changes in soil conditions (where many Orthoptera species lay their eggs) or other habitat changes driven by nitrogen have a stronger influence than food related traits. To fully evaluate the negative effects of nitrogen deposition on higher trophic levels it is essential to take into account species life-history traits.

The genome of wine yeast Dekkera bruxellensis provides a tool to explore its food-related properties

The yeast Dekkera/Brettanomyces bruxellensis can cause enormous economic losses in wine industry due to production of phenolic off-flavor compounds. D. bruxellensis is a distant relative of baker's yeast Saccharomyces cerevisiae. Nevertheless, these two yeasts are often found in the same habitats and share several food-related traits, such as production of high ethanol levels and ability to grow without oxygen. In some food products, like lambic beer, D. bruxellensis can importantly contribute to flavor development. We determined the 13.4Mb genome sequence of the D. bruxellensis strain Y879 (CBS2499) and deduced the genetic background of several “food-relevant” properties and evolutionary history of this yeast. Surprisingly, we find that this yeast is phylogenetically distant to other food-related yeasts and most related to Pichia (Komagataella) pastoris, which is an aerobic poor ethanol producer. We further show that the D. bruxellensis genome does not contain an excess of lineage specific duplicated genes nor a horizontally transferred URA1 gene, two crucial events that promoted the evolution of the food relevant traits in the S. cerevisiae lineage. However, D. bruxellensis has several independently duplicated ADH and ADH-like genes, which are likely responsible for metabolism of alcohols, including ethanol, and also a range of aromatic compounds.

Sensory education decreases food neophobia score and encourages trying unfamiliar foods in 8–12-year-old children

The effects of sensory education on food-related traits and responses to food were examined over a period of 1.5 years in school children. Children ( N = 164, 8- and 11-year-old at baseline) from two schools in Helsinki were divided in an education group (E; N = 92) receiving up to two waves of sensory lessons, and a control group (C; N = 72) participating in baseline and follow-up measurements only. The 1st wave (10 lessons) followed the principles of the French program “ Classes du goût” and the 2nd wave (5 extensive lessons to 2/3 of the E group) concentrated on different food categories. A questionnaire assessing children’s liking and familiarity of unfamiliar and familiar foods and food neophobia, was sent to parents at the baseline and after each wave of sensory lessons. After education, the E group had tried a larger proportion of unfamiliar foods than at the baseline. The number of tasted foods in the C group remained at the baseline level. Food neophobia score decreased in the E group, while no change was seen in the C group. The effects of education were stronger in the younger children. Thus, sensory education has potential to activate children to try new foods and thereby to increase variety in their diets.

The Drosophila foraging Gene Mediates Adult Plasticity and Gene–Environment Interactions in Behaviour, Metabolites, and Gene Expression in Response to Food Deprivation

Nutrition is known to interact with genotype in human metabolic syndromes, obesity, and diabetes, and also in Drosophila metabolism. Plasticity in metabolic responses, such as changes in body fat or blood sugar in response to changes in dietary alterations, may also be affected by genotype. Here we show that variants of the foraging (for) gene in Drosophila melanogaster affect the response to food deprivation in a large suite of adult phenotypes by measuring gene by environment interactions (GEI) in a suite of food-related traits. for affects body fat, carbohydrates, food-leaving behavior, metabolite, and gene expression levels in response to food deprivation. This results in broad patterns of metabolic, genomic, and behavioral gene by environment interactions (GEI), in part by interaction with the insulin signaling pathway. Our results show that a single gene that varies in nature can have far reaching effects on behavior and metabolism by acting through multiple other genes and pathways.

The foraging gene of Drosophila melanogaster: Spatial‐expression analysis and sucrose responsiveness

The ability to identify and respond to food is essential for survival, yet little is known about the neural substrates that regulate natural variation in food-related traits. The foraging (for) gene in Drosophila melanogaster encodes a cGMP-dependent protein kinase (PKG) and has been shown to function in food-related traits. To investigate the tissue distribution of FOR protein, we generated an antibody against a common region of the FOR isoforms. In the adult brain we localized FOR to neuronal clusters and projections including neurons that project to the central complex, a cluster within the dorsoposterior region of the brain hemispheres, a separate cluster medial to optic lobes and lateral to brain hemispheres, a broadly distributed frontal-brain cluster, axon bundles of the antennal nerve and of certain subesophageal-ganglion nerves, and the medulla optic lobe. These newly described tissue distribution patterns of FOR protein provide candidate neural clusters and brain regions for investigation of neural networks that govern foraging-related traits. To determine whether FOR has a behavioral function in neurons we expressed UAS-for in neurons using an elav-gal4 driver and measured the effect on adult sucrose responsiveness (SR), known to be higher in rovers than sitters, the two natural variants of foraging. We found that pan-neuronal expression of for caused an increase in the SR of sitters, demonstrating a neural function for PKG in this food-related behavior.