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Sugar allocation from source to sink (young) leaves, critical for plant development, relies on activities of plasma membrane sugar transporters. However, the key sugar unloading mechanism to sink leaves remains elusive. SWEET transporters mediate sugar efflux into reproductive sinks; therefore, they are promising candidates for sugar unloading during leaf growth. Transcripts of SlSWEET1a , belonging to clade I of the SWEET family, were markedly more abundant than those of all other 30 SlSWEET genes in young leaves of tomatoes. High expression of SlSWEET1a was also detected in reproductive sinks, such as flowers. SlSWEET1a was dominantly expressed in leaf unloading veins, and the green fluorescent protein (GFP) fusion protein was localized to the plasma membrane using Arabidopsis protoplasts, further implicating this carrier in sugar unloading. In addition, yeast growth assays and radiotracer uptake analyses further demonstrated that Sl SWEET1a acted as a low-affinity (K m ~100 mM) glucose-specific carrier with a passive diffusion manner. Finally, virus-induced gene silencing of SlSWEET1a expression reduced hexose accumulation to ~50% in young leaves, with a parallel 2-fold increase in mature leaves. Thus, we propose a novel function for Sl SWEET1a in the uptake of glucose into unloading cells as part of the sugar unloading mechanism in sink leaves of tomato. [ABSTRACT FROM AUTHOR]

Background The relation between taste perception, diet, and adiposity remains controversial. Additionally, there is a lack of knowledge on the polymorphisms influencing taste given the scarcity of genome-wide association studies (GWASs) published. Objectives We studied the relation between perception of the basic tastes, i.e. sweet, salty, bitter, sour, and umami (separately and jointly in a "taste score"), and anthropometric measurements in older subjects with metabolic syndrome (MetS). GWASs were undertaken to identify genes associated with basic tastes and their score. Methods Taste perception was cross-sectionally determined by challenging subjects (381 older individuals with MetS) with solutions (5 concentrations) of the basic tastes with the use of standard prototypical tastants (phenylthiocarbamide and 6- n -propylthiouracil, NaCl, sucrose, monopotassium glutamate, and citric acid, for bitter, salt, sweet, umami, and sour, respectively). Taste perception intensities were expressed on a scale. A total taste score was derived. Results The total taste score was inversely associated with body weight, body mass index, and waist circumference (P  < 0.05). Subjects having a total taste score higher than or equal to the median (11 points for concentration V) were less likely to be classified as obese than subjects below the median (OR: 0.36; 95% CI: 0.22, 0.59; P  < 0.001). Associations were similar, albeit less strong, for some taste qualities. In the GWASs, the highest associations were for bitter taste (rs1726866- TAS2R38, with P  = 7.74 × 10−18 for phenylthiocarbamide and P  = 3.96 × 10−19 for 6- n -propylthiouracil). For other tastes, several single-nucleotide polymorphisms (SNPs) exceeded the P threshold of 1 × 10−5. However, the top-ranked SNPs independently explained a low percentage of taste variability, hence their use as single proxies for the association between taste perception and adiposity is limited. Conclusions We found a strong inverse association between greater taste perception and body weight, body mass index, and waist circumference in older subjects with MetS and identified some taste-related SNPs. It would be advantageous to identify additional genetic proxies for taste and to develop polygenic scores. Data used in this study were derived from the clinical trial PREDIMED PLUS at baseline, registered at http://www.isrctn.com as ISRCTN89898870. [ABSTRACT FROM AUTHOR]

Abstract Functional neuroimaging studies have identified brain regions associated with human taste perception, but only a few have investigated the associations with brain structure. Here, in this exploratory study, we examined the association between the volumes of 82 regions of interest (ROI) and the perceived intensities of sweet (a weighted mean rating of glucose, fructose, aspartame, neohesperidin dihydrochalcone) and bitter (propylthiouracil, quinine, caffeine) substances in a large Australian healthy cohort from the Queensland Twin IMaging (QTIM, n = 559) study and the perceived intensity of quinine in a large U.S. healthy cohort from the Human Connectome Project (HCP, n = 1101). In QTIM, the volumes of 3 cortical (right cuneus gyrus, left transverse temporal gyrus, right inferior temporal gyrus) and one subcortical structure (both left and right caudate) were associated with more than one taste stimulus (P < 0.05) and tended to be associated with both sweet and bitter tastes in the same direction, suggesting these ROIs were more broadly tuned for taste sensation. A further 11 ROIs were associated with a specific taste (sweetness : 4; propylthiouracil : 3; caffeine : 2; quinine : 2). In HCP, volumes of 5 ROIs were associated with quinine bitterness. The quinine-left entorhinal cortex association was found in both QTIM (r = -0.12, P = 3.7 × 10−3) and HCP (r = -0.06, P = 2.0 × 10−2). This study provides the first evidence that, even in healthy people, variation in brain structure is associated with taste intensity ratings, and provides new insights into the brain gustatory circuit. [ABSTRACT FROM AUTHOR]

Sophorolipids (SL) are typically produced and secreted by select nonpathogenic yeast species (i.e., Candida) from renewable substrates. They are currently being used by industry on a limited basis in formulations for cleaning solutions as well as laundry and dishwashing detergents. Due to the nature of their chemical structure, it was hypothesized that SL would demonstrate taste‐sensory properties. In this study, SL were produced via fermentation on a mixed substrate platform with glucose and either palmitic acid, stearic acid, or oleic acid using Candida (currently reclassified as Starmerella) bombicola ATCC 22214. The taste properties of SL were determined using a single‐cell manual calcium imaging technique on cultured human fungiform taste papillae (HBO) cells. The results of those studies demonstrated that sweetener‐responsive HBO cells also respond to SL, and these responses are mediated by the type 1 taste receptors 3 (T1R3), because they were blocked by lactisole (a T1R3 receptor‐specific blocker). The involvement of the T1R3 receptor in SL recognition was confirmed via the chorda tympani nerve recording (CTNR) study in a (−/−) T1R3 knockout (KO) mouse model. We further demonstrated that SL are capable of blocking the bitter stimuli‐elicited responses both in HBO cells and in the CTNR study. This is the first report demonstrating that SL have taste‐sensory properties, which opens up numerous possibilities for practical applications of SL to ameliorate bitter tastes in foods and drugs and understand the potential source of dysgeusia in some patients. [ABSTRACT FROM AUTHOR]

Summary: Cotton is white gold across the globe and composed of fiber cells derived from the outer integument of cotton ovules. Fiber elongation uses sucrose as a direct carbon source. The molecular mechanism transcriptionally controlling sucrose transport from ovules into the elongating fibers remains elusive.In this study the involvement of GhMYB212 in the regulation of sucrose transportion into expanding fibers was investigated. GhMYB212 RNAi plants (GhMYB212i) accumulated less sucrose and glucose in developing fibers, and had shorter fibers and a lower lint index. RNA‐seq and protein−DNA binding assays revealed that GhMYB212 was closely linked to the pathways of sucrose and starch transportation and metabolism, directly controling the expression of a sucrose transporter gene GhSWEET12.GhSWEET12 RNAi plants (GhSWEET12i) possessed similar fiber phenotypes to those of GhMYB212i. Exogenous sucrose supplementation in ovule cultures did not rescue the shorter fiber phenotype of GhMYB212i and GhSWEET12i. This finding supported the idea that the attenuated rate of sucrose transport from the outer seed coat into the fibers is responsible for the retardation of fiber elongation.Current investigations support the idea that GhMYB212 functions as the main regulator of fiber elongation by controlling the expression of GhSWEET12, and therefore it is important to study cell expansion and sugar transportation during seed development. [ABSTRACT FROM AUTHOR]

Automatic detection of important and unexpected stimuli in the visual environment is crucial for survival. We sought to explore whether visual food stimuli are detected already in the pre-attentive stimulus processing phase, and whether hunger enhances such automatic detection. To attain these goals, we adapted an electroencephalography paradigm - visual mismatch negativity (vMMN). vMMN is a useful paradigm to study the processing of salient emotional stimuli which has not yet been applied in the context of eating behaviours. In our study, 18 right-handed women (25.2 ± 7.4 years) underwent two experimental sessions: hunger and fed conditions. Participants had to focus on a 2-back working memory task in the center of the computer screen, while stimuli depicting high fat savoury (HFSA) and high fat sweet (HFSW) foods were presented as deviants in a stream of neutral standard stimuli in the four corners of the screen. Automatic detection of foods was observed within 80-360 ms after stimulus onset, although some foods were better detected than the others. In HFSA, hunger enhanced the processing of all deviant stimuli in the early (100-160 ms) and mid-latency (160-220 ms) time windows. As the modulating effect of hunger was not food-specific, hunger may enhance automatic detection of changes in the visual environment, regardless of the type of input. Nevertheless, hamburger in HFSA was better detected than other stimuli, indicated by larger peak amplitudes, which supports the food-specificity of hunger modulation. In HFSW, the modulating effect of hunger was not observed, possibly due to suboptimally chosen stimuli within this block. In conclusion, we believe that after careful stimulus selection vMMN has a great potential to be a reliable measure of early food-cue processing. [ABSTRACT FROM AUTHOR]

Abstract Although the natural florescence of the tree peony is short, it can be lengthened by forcing culture. In this study, both defoliation or gibberellic acid (GA 3) treatment individually induced tree peony (Paeonia suffruticosa 'Luo Yang Hong') flowering under forcing culture, and their combination (D + G) accelerated flowering with a GA 3 -overdose-like phenomenon, indicating that synergism between defoliation and GA 3 treatment may occur. Both defoliation and GA 3 treatment induced a GA response, including (i) increased GA 3 production, (ii) increased PsCPS and PsGA3ox expression, and (iii) decreased PsGA2ox , PsGID1c , and PsGID2 expression; both treatments also positively influenced non-structural carbohydrate (NSC) accumulation. According to the expression of five PsSWEETs , PsSWEET2 and PsSWEET17 may redundantly exercise the crosstalk of defoliation and GA 3 treatment by NSC distribution, whereas PsSWEET12 may act by GA modulation; no synergism resulting from the D + G treatment was detected. Tissue-specific analysis indicated that, in sepals, PsSWEET2 and PsSWET7 are both induced by defoliation and GA 3 treatment, whereas PsSWEET2 expression showed synergism with the D + G treatment. In summary, defoliation and GA 3 treatment synergistically induce tree peony flowering under forcing culture, and NSCs are suggested as key intermedia. Moreover, sepals may play key roles in their synergism, although more direct evidence is still needed. [ABSTRACT FROM AUTHOR]

Background: The SWEET proteins are a group of sugar transporters that play a role in sugar efflux during a range of biological processes, including stress responses. However, there has been no comprehensive analysis of the SWEET family genes in Brassica oleracea (BoSWEET), and the evolutionary pattern, phylogenetic relationship, gene characteristics of BoSWEET genes and their expression patterns under biotic and abiotic stresses remain largely unexplored. Results: A total of 30 BoSWEET genes were identified and divided into four clades in B. oleracea. Phylogenetic analysis of the BoSWEET proteins indicated that clade II formed first, followed by clade I, clade IV and clade III, successively. Clade III, the newest clade, shows signs of rapid expansion. The Ks values of the orthologous SWEET gene pairs between B. oleracea and Arabidopsis thaliana ranged from 0.30 to 0.45, which estimated that B. oleracea diverged from A. thaliana approximately 10 to 15 million years ago. Prediction of transmembrane regions showed that eight BoSWEET proteins contain one characteristic MtN3_slv domain, twenty-one contain two, and one has four. Quantitative reverse transcription-PCR (qRT-PCR) analysis revealed that five BoSWEET genes from clades III and IV exhibited reduced expression levels under chilling stress. Additionally, the expression levels of six BoSWEET genes were up-regulated in roots of a clubroot-susceptible cabbage cultivar (CS-JF1) at 7 days after inoculation with Plasmodiophora brassicae compared with uninoculated plants, indicating that these genes may play important roles in transporting sugars into sink roots associated with P. brassicae colonization in CS-JF1. Subcellular localization analysis of a subset of BoSWEET proteins indicated that they are localized in the plasma membrane. Conclusions: This study provides important insights into the evolution of the SWEET gene family in B. oleracea and other species, and represents the first study to characterize phylogenetic relationship, gene structures and expression patterns of the BoSWEET genes. These findings provide new insights into the complex transcriptional regulation of BoSWEET genes, as well as potential candidate BoSWEET genes that promote sugar transport to enhance chilling tolerance and clubroot disease resistance in cabbage. [ABSTRACT FROM AUTHOR]

Background: Children exposed to gestational diabetes mellitus (GDM) in utero are at high-risk of obesity. Given that nutritional habits can track from infancy to childhood, the aim of this study was to evaluate the association between the timing of fruit juice introduction in infancy and later consumption of sweet-tasting foods and beverages among children exposed (GDM+) and unexposed (GDM-) to GDM.Methods: A total of 107 GDM+ and 59 GDM- participated in the project. Data on the timing of fruit juice introduction during infancy were retrospectively collected for 62 GDM+ and 32 GDM- children. Current dietary intakes were collected with two 24-hour dietary recall questionnaires. Children were divided into groups according to the median timing of juice introduction (9 months).Results: Mean age of children was 6.3 ± 2.6 and 7.6 ± 3.7 years for GDM+ and GDM- children, respectively (p = 0.08). Mean age of fruit juice introduction was similar between groups (p > 0.05). Consuming >1 serving of fruit juice per day was 2.72 times more prevalent among GDM+ children introduced to fruit juice <9 months, compared to GDM+ children introduced ≥9 months (CI: 1.19-6.20). This association was not observed in the GDM- group. The timing of fruit juice introduction was not associated with later consumption of sweets, desserts and sweet-tasting beverages when adjustment for children's age was made among GDM+ and GDM- children.Conclusion: Early introduction of fruit juice in infant diet is associated with higher prevalence of consumption of >1 serving of fruit juice per day in GDM+ children. [ABSTRACT FROM AUTHOR]

As "taste" is a primary driver of food choice, the objective of this study was to understand how the sensory properties of diets relate to energy intake (EI). A database of 720 frequently consumed foods, described by a trained panel for basic tastes (sweetness, saltiness) and fatty mouthfeel, was systematically applied to all foods reportedly consumed in 24hr recalls as part of the 2011-2012 Australian National Nutrition and Physical Activity Survey (n = 12,153 adults and children). Food groups were classified according to the Australian Guide to Healthy Eating, and their contribution to total nutrient and sensory intake estimated. There were significant positive correlations between the nutrient and sensory properties of diets, for example, for adults, EI and fatty mouthfeel r = 0.740; EI and saltiness r = 0.623 and EI and sweetness r = 0.517 (all p < 0.01). Core foods (e.g. fruits, vegetables, grains, dairy) can provide similar sensory stimulation whilst being of lower energy content than discretionary foods (e.g. confectionary, snacks). Regression models in adults, controlling for age, sex and BMI, revealed that fatty mouthfeel (β = 0.492), saltiness (β = 0.161) and sweetness (β = 0.138) were significant predictors of EI, explaining 56% variance (p < 0.01). Similar results were found for children. Fatty mouthfeel was the primary driver of energy intake but such sensory stimulation can be derived from core (e.g. dairy foods), rather than discretionary foods, at lower energy content. [ABSTRACT FROM AUTHOR]

Preclinical studies provided some important insights into the action of glucagon-like peptide 1 (GLP-1) in taste perception. This review examines the literature to uncover some molecular mechanisms and connections between GLP-1 and the gustatory coding. Local GLP-1 production in the taste bud cells, the expression of GLP-1 receptor on the adjacent nerves, a functional continuum in the perception of sweet chemicals from the gut to the tongue and an identification of GLP-1 induced signaling pathways in peripheral and central gustatory coding all strongly suggest that GLP-1 is involved in the taste perception, especially sweet. However, the impact of GLP-1 based therapies on gustatory coding in humans remains largely unaddressed. Based on the molecular background we encourage further exploration of the tongue as a new treatment target for GLP-1 receptor agonists in clinical studies. Given that pharmacological manipulation of gustatory coding may represent a new potential strategy against obesity and diabetes, the topic is of utmost clinical relevance.

Studies of adults report that perceived taste affects food choices and intake, which in turn may have an impact on health. However, corresponding evidence on adolescents is limited. Our aim was to summarize current evidence of the impact of taste perception on food choice preferences or dietary intakes among adolescents (mean age 10–19.9 years). Systematic searches identified 13 papers, 12 cross-sectional and one cohort study published between 1 January 2000 to 20 February 2020 assessing the impact of taste (using phenotypic and/or genotypic markers) on food choices in adolescents without any disease conditions. Qualitative assessment in the current review indicated that individuals sensitive to bitter tastes often have a lower preference of bitter-tasting food and higher preference for sweet-tasting food. A meta-analysis of three studies on bitter-taste sensitivity revealed no difference in preference for bitter-tasting vegetables between bitter tasters and non-tasters (standardized mean difference (SMD) = 0.04; 95% CI: −0.18, 0.26; p = 0.72). Overall, a limited number of studies were available for review. As a result, we report no clear relationship between taste perception and food choices or intake in adolescents. More studies are needed to evaluate the link between adolescents’ taste perceptions and dietary intake.

Factors associated with sweetness preference are multi-faceted and incredibly complex. A scoping review was undertaken to identify determinants of sweetness preference in humans. Using an online search tool, ProQuest ™, a total of 99 publications were identified and subsequently grouped into the following categories of determinants: Age, dietary factors, reproductive hormonal factors, body weight status, heritable, weight loss, sound, personality, ethnicity and lifestyle, previous exposure, disease, and ‘other’ determinants. Methodologies amongst studies were heterogenous in nature (e.g., there was variability across studies in the sweetness concentrations tested, the number of different sweetness concentrations used to assess sweetness preference, and the methods utilized to measure sweetness preference), rendering interpretation of overall findings challenging; however, for certain determinants, the evidence appeared to support predictive capacity of greater sweetness preference, such as age during certain life-stages (i.e., young and old), being in a hungry versus satiated state, and heritable factors (e.g., similar sweetness preferences amongst family members). Recommendations for the design of future studies on sweetness preference determinants are provided herein, including an “investigator checklist” of criteria to consider.

Aroma-taste interactions, which are believed to occur due to previous coexposure (concurrent presence of aroma and taste), have been suggested as a strategy to aid sugar reduction in food and beverages. However, coexposures might be influenced by individual differences. We therefore hypothesized that aroma-taste interactions vary across individuals. The present study investigated how individual differences (gender, age, and sweet liker status) influenced the effect of aroma on sweetness intensity among young adults. An initial screening of five aromas, all congruent with sweet taste, for their sweetness enhancing effect was carried out using descriptive analysis. Among the aromas tested, vanilla was found most promising for its sweet enhancing effects and was therefore tested across three sucrose concentrations by 129 young adults. Among the subjects tested, females were found to be more susceptible to the sweetness enhancing effect of vanilla aroma than males. For males, the addition of vanilla aroma increased the sweet taste ratings significantly for the 22−25-year-olds, but not the 19−21-year-olds. Consumers were clustered according to their sweet liker status based on their liking for the samples. Although sweet taste ratings were found to vary with the sweet liker status, aroma enhanced the sweetness ratings similarly across clusters. These results call for more targeted product development in order to aid sugar reduction.

The sweet-mellow taste sensation is a unique and typical feature of premium congou black tea infusions. To explore the key taste-active compounds that influence the sweet-mellow taste, a sensory and molecular characterization was performed on thirty-three congou black tea infusions presenting different taste qualities, including the sweet-mellow, mellow-pure, or less-mellow taste. An integrated application of quantitative analysis of 48 taste-active compounds, taste contribution analysis, and further validation by taste supplementation experiments, combined with human sensory evaluation revealed that caffeine, γ-aminobutyric acid, rutin, succinic acid, citric acid, and gallic acid negatively affect the sweet-mellow taste, whereas glucose, sucrose, and ornithine positively contribute to the sweet-mellow taste of congou black tea infusions. Particularly, rutin, γ-aminobutyric acid, gallic acid, and caffeine, which impart the major inhibitory effect to the manifestation of the sweet-mellow taste, were identified as the key influencing components through stepwise screening and validation experiments. A modest level of these compounds was found to be favorable for the development and manifestation of the sweet-mellow taste. These compounds might potentially serve as the regulatory targets for oriented-manufacturing of high-quality sweet-mellow congou black tea.

Sugars Will Eventually be Exported Transporter (SWEET) and SemiSWEET are recently characterized families of sugar transporters in eukaryotes and prokaryotes, respectively. SemiSWEETs contain 3 transmembrane helices (TMHs), while SWEETs contain 7. Here, we performed sequence-based comprehensive analyses for SWEETs and SemiSWEETs across the biosphere. In total, 3,249 proteins were identified and ≈60% proteins were found in green plants and Oomycota, which include a number of important plant pathogens. Protein sequence similarity networks indicate that proteins from different organisms are significantly clustered. Of note, SemiSWEETs with 3 or 4 TMHs that may fuse to SWEET were identified in plant genomes. 7-TMH SWEETs were found in bacteria, implying that SemiSWEET can be fused directly in prokaryote. 15-TMH extraSWEET and 25-TMH superSWEET were also observed in wild rice and oomycetes, respectively. The transporters can be classified into 4, 2, 2, and 2 clades in plants, Metazoa, unicellular eukaryotes, and prokaryotes, respectively. The consensus and coevolution of amino acids in SWEETs were identified by multiple sequence alignments. The functions of the highly conserved residues were analyzed by molecular dynamics analysis. The 19 most highly conserved residues in the SWEETs were further confirmed by point mutagenesis using SWEET1 from Arabidopsis thaliana. The results proved that the conserved residues located in the extrafacial gate (Y57, G58, G131, and P191), the substrate binding pocket (N73, N192, and W176), and the intrafacial gate (P43, Y83, F87, P145, M161, P162, and Q202) play important roles for substrate recognition and transport processes. Taken together, our analyses provide a foundation for understanding the diversity, classification, and evolution of SWEETs and SemiSWEETs using large-scale sequence analysis and further show that gene duplication and gene fusion are important factors driving the evolution of SWEETs.

The perception of taste is determined by several factors, including genetics, which at the same time is related with the diet and diseases in different populations. We aimed to identify the frequency of six single nucleotide polymorphisms (rs307355, rs35744813, rs713598, rs1726866, rs10246939 and rs11091046) involved in the perception of sweet, bitter and salty flavor in Ecuadorian mestizo population. It was found that the presence of the T allele of rs307355 and rs35744813 is associated with decreased ability of subjects to carry out specific discrimination of sweetness, this is particularly interesting given the correlation found (p = 0.0022) between sucrose perception and family history of cancer and diabetes. Furthermore, rs713598, rs1726866 and rs10246939 do not influence the ability to perceive the bitter taste. Concerning the perception of the salty taste, rs11091046 does influence the capacity of detecting it more easily. This theoretical knowledge of the genetic influence on taste perception can contribute to the understanding of eating habits and their impact on human health. [ABSTRACT FROM AUTHOR]

Sensory impairments are critical for diagnosing and characterizing neurodevelopmental disorders. Taste is a sensory modality often not well characterized. Engrailed-2 ( En2 ) is a transcription factor critical for neural development, and mice lacking En2 ( En2 −/− ) display signs of impaired social interaction, cognitive processes (e.g., learning and memory, conditioned fear), and neurodevelopmental alterations. As such, En2 −/− mice display the behavioral deficits and neural impairments characteristic of the core symptoms associated with autism spectrum disorder (ASD). The objective of this study was to characterize the taste function in En2 −/− compared with En2 +/+ in adult male mice. Measuring taste responsiveness by an automated gustometer, En2 null mice had decreased lick responses for 1.6 M fructose, whereas they demonstrated an increased taste responsivity (i.e., relative to water) at 0.3 M sodium chloride and 1 M monosodium glutamate. In a separate cohort of mice, En2 −/− mice had an increased preference for sodium chloride over a range of concentrations (0.032–0.3 M) compared with En2 +/+ mice. Regional gene expression of the tongue epithelium demonstrated an increase in Scnn1a , T2R140 , T1R3, and Trpm5 and a decrease in Pkd1l3 in En2 null mice. Taken together, such data indicate that deficits in En2 can produce sensory impairments that can have a measurable impact on taste, particularly salt taste. [ABSTRACT FROM AUTHOR]

Taste and flavor (retronasal olfaction) interact in the brain. The rules of that interaction are not well understood. This study uses 2 taste modifiers that alter sweet to examine the effects on flavors. Subjects used the Global Sensory Intensity Scale to assess the aroma, sweetness, sourness, and flavor of 10 foods. As previous work had shown, miracle fruit added sweetness to acids, which secondarily reduced sourness (mixture suppression) and Gymnema sylvestre reduced sweetness in sweet foods as well as the sweetness induced by miracle fruit. In this study, multiple regression showed that both sweet and sour contribute to flavor. Gymnema sylvestre reduced the perceived sweet of predominantly sweet foods (chocolate and maple syrup) as expected; reducing the sweet, reduced the flavor. The effects of miracle fruit were complicated by its dual action: intensification of sweet and reduction of sour. Predominantly sour foods (vinegar, lemon, mustard, pickle) were sweetened by miracle fruit but any flavor enhancement associated with the added sweet appears to have been countered by the flavor reduction associated with reduced sourness. Moderately sour foods that are also sweet (tomatoes, strawberries) were sweetened by miracle fruit and thus flavor was enhanced; flavor loss through sour reduction was apparently not sufficient to counter the flavor enhancement due to increased sweet so the net result was that tomato and strawberry flavors were enhanced. The flavors of control foods (not predominantly sweet or sour [sausage, peanuts]) showed only small changes. [ABSTRACT FROM AUTHOR]

Taste is important for food intake. The fetus first experiences taste through amniotic fluid, and later via mother's milk. Early human experience with taste has a key importance for later acceptance of food. Dietary behavior is determined by the interaction of many different factors. The development of the olfactory and taste receptors begins at 7-8 weeks of gestation. An early sensitive period probably exists when flavor preference is established. Sweet taste is preferred in early childhood; this is the reason why children are at increased risk of over-consuming saccharides. Gustatory sensitivity declines with age. The threshold for the perception of each basic taste differs, and is established genetically. In this review, we summarize published data on taste preferences and its development and changes during life. [ABSTRACT FROM AUTHOR]

This study aims at understanding how preference and sensitivity to the basic tastes develop in the preschool years, and how the two relate to each other. To expand on the existing literature regarding taste preferences conducted in cross-sectional studies, a longitudinal design was applied with children from age four to six years old. During the springs of 2015, 2016, and 2017, 131 children born in 2011 were tested in their kindergartens. To investigate preferences for sweet, sour and bitter tastes, the children performed ranking-by-elimination procedures on fruit-flavored beverages and chocolates with three taste intensity levels. The beverages varied in either sucrose, citric acid, or the bitter component isolone. The chocolates varied in the bitter component theobromine from cocoa and sucrose content. Each year, the children also performed paired-comparison tasks opposing plain water to tastant dilutions at four concentrations. The stimuli consisted of the five basic tastes: sweet (sucrose) sour (citric acid monohydrate) umami (monosodium glutamate), salty (sodium chloride), and bitter (quinine hydrochloride dihydrate). Preference for sweetness levels increased with age, while preference for bitterness and sourness levels were stable. Concerning taste sensitivity, the children showed an increase in sensitivity for sourness and saltiness, a decrease for sweetness, and stability for umami and bitterness. A negative association was found between sweetness sensitivity and preference for sweetness. The study highlights different trajectories of sensitivity and preferences across tastes. On average, a reduction in sweetness sensitivity combined with an increase in preference for higher sweetness was observed from the age of four to six. The weak relationship between taste sensitivity and taste preference in our data suggests that taste preference development is shaped by a multitude of factors in addition to taste sensitivity. [ABSTRACT FROM AUTHOR]

Sucrose is produced in mesophyll cells and transferred into phloem cells before it is delivered long-distance to sink tissues. However, little is known about how sucrose transport is regulated in plants. Here, we identified a T-DNA insertional mutant of Oryza sativa DNA BINDING WITH ONE FINGER 11 ( OsDOF11 ), which is expressed in the vascular cells of photosynthetic organs and in various sink tissues. The osdof11 mutant plants are semi-dwarf and have fewer tillers and smaller panicles as compared with wild-type (WT) plants. Although sucrose enhanced root elongation in young WT seedlings, this enhancement did not occur in osdof11 seedlings due to reduced sucrose uptake. Sugar transport rate analyses revealed that less sugar was transported in osdof11 plants than in the WT. Expression of four Sucrose Transporter (SUT) genes— OsSUT1 , OsSUT3 , OsSUT4 , and OsSUT5— as well as two Sugars Will Eventually be Exported Transporters (SWEET) genes, OsSWEET11 and OsSWEET14 , was altered in various organs of the mutant, including the leaves. Chromatin immunoprecipitation assays showed that OsDOF11 directly binds the promoter regions of SUT1 , OsSWEET11 , and OsSWEET14 , indicating that the expression of these transporters responsible for sucrose transport via apoplastic loading is coordinately controlled by OsDOF11. We also observed that osdof11 mutant plants were less susceptible to infection by Xanthomonas oryzae pathovar oryzae , suggesting that OsDOF11 participates in sugar distribution during pathogenic invasion. Collectively, these results suggest that OsDOF11 modulates sugar transport by regulating the expression of both SUT and SWEET genes in rice. [ABSTRACT FROM AUTHOR]

Distribution patterns and finely-tuned concentration gradients of plant hormones govern plant growth and development. Gibberellin (GA) is a plant hormone regulating key processes in plants; many of them are of significant agricultural importance, such as seed germination, root and shoot elongation, flowering, and fruit patterning. Although studies have demonstrated that GA movement is essential for multiple developmental aspects, how GAs are transported throughout the plant and where exactly they accumulate remain largely unknown. Here, we summarize recent findings from studies of GA movement and localization, and discuss the importance of GA intermediates in long- and short-distance movement. We further review recently identified Arabidopsis GA transporters and highlight their complex specialization and robust functional redundancy in GA transport activity. [ABSTRACT FROM AUTHOR]

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Summary: Despite the relevance of seed‐filling mechanisms for crop yield, we still have only a rudimentary understanding of the transport processes that supply the caryopsis with sugars. We hypothesized that SWEET sucrose transporters may play important roles in nutrient import pathways in the rice caryopsis. We used a combination of mRNA quantification, histochemical analyses, translational promoter–reporter fusions and analysis of knockout mutants created by genomic editing to evaluate the contribution of SWEET transporters to seed filling. In rice caryopses, SWEET11 and 15 had the highest mRNA levels and proteins localized to four key sites: all regions of the nucellus at early stages; the nucellar projection close to the dorsal vein; the nucellar epidermis that surrounds the endosperm; and the aleurone. ossweet11;15 double knockout lines accumulated starch in the pericarp, whereas caryopses did not contain a functional endosperm. Jointly, SWEET11 and 15 show all the hallmarks of being necessary for seed filling with sucrose efflux functions at the nucellar projection and a role in transfer across the nucellar epidermis/aleurone interface, delineating two major steps for apoplasmic seed filling, observations that are discussed in relation to observations made in rice and barley regarding the relative prevalence of these two potential import routes. [ABSTRACT FROM AUTHOR]

The objective of this study was to perform an internal validation of a questionnaire assessing 7–12 years old children’s liking for saltiness, sweetness and fattiness in foods. An 83-item questionnaire validated in adults was adapted for children via vocabulary adaptation, picture addition and removal of little known or consumed items. It was launched online, and a paper version was also available. The construct validity was evaluated in 500 French children aged 7–12 y. An exploratory factor analysis (EFA) was performed to identify the factor structure within each sensation. The adult liking factor structure was also tested on the children’s data to compare the factor structures between adults and children. A confirmatory factor analysis (CFA) was performed to validate the factor structure. Finally, a bootstrap analysis was performed to ensure the stability of the structure. Liking for saltiness, sweetness, fattiness-and-saltiness and fattiness-and-sweetness sensations showed meaningful factor structures. After the deletion of some items, a one-factor structure was identified for the liking for saltiness (9 items), and multiple-factor structures were identified for the liking for sweetness (16 items), fattiness-and-saltiness (22 items), and fattiness-and-sweetness (16 items). A fattiness model was estimated based on two subscales, the fattiness-and-saltiness and fattiness-and-sweetness subscales. This self-administered questionnaire, available on line or on paper, enables the creation of a factor structure for saltiness, sweetness, fattiness-and-saltiness, fattiness-and-sweetness, and fattiness liking in children. This questionnaire represents the first self-administered tool designed to assess children’s liking for sweetness, saltiness and fattiness sensations in large cohorts. [ABSTRACT FROM AUTHOR]

Objectives: Recent research has shown that taste receptors in airway epithelial cells are involved in defending against upper respiratory tract infection. The aim of the present study was to investigate gustatory function in patients with chronic rhinosinusitis (CRS). Methods: Taste function was assessed using the extended "taste strip" test in 37 patients with CRS (20 males, 17 females; mean age = 32.1 years; range, 20-82 years) and 135 healthy controls (70 males, 65 females; mean age = 29.5 years; range, 18-84 years). Results: The mean (±SD) total extended taste score was 12.8 (±3.5) in patients and 14.5 (±3.2) in controls. Analysis of variance indicated an interaction of sinusitis and gender (P < .05) with significantly lower total scores and significantly poorer results for the bitter taste among male patients compared to controls (P < .01). In addition, CRS patients exhibited a trend toward decreased sweet taste perception compared to controls, but this did not reach significance (P = .051). Conclusions: Patients with CRS exhibited decreased gustatory function compared to healthy controls. The effect was most pronounced for bitter taste. Thus, the assessment of gustatory function seems to be useful for detecting potential risk factors for recurrent upper respiratory tract infection. [ABSTRACT FROM AUTHOR]

Key message: Thirteen SWEET transporters were identified in Camellia sinensis and the cold-suppression gene CsSWEET16 contributed to sugar compartmentation across the vacuole and function in modifying cold tolerance in Arabidopsis.Abstract: The sugars will eventually be exported transporters (SWEET) family of sugar transporters in plants is a recently identified protein family of sugar uniporters that contain seven transmembrane helices harbouring two MtN3 motifs. SWEETs play important roles in various biological processes, including plant responses to environmental stimuli. In this study, 13 SWEET transporters were identified in Camellia sinensis and were divided into four clades. Transcript abundances of CsSWEET genes were detected in various tissues. CsSWEET1a/1b/2a/2b/2c/3/9b/16/17 were expressed in all of the selected tissues, whereas the expression of CsSWEET5/7/9a/15 was not detected in some tissues, including those of mature leaves. Expression analysis of nine CsSWEET genes in leaves in response to abiotic stresses, natural cold acclimation and Colletotrichum camelliae infection revealed that eight CsSWEET genes responded to abiotic stress, while CsSWEET3 responded to C. camelliae infection. Functional analysis of 13 CsSWEET activities in yeast revealed that CsSWEET1a/1b/7/17 exhibit transport activity for glucose analogues and other types of hexose molecules. Further characterization of the cold-suppression gene CsSWEET16 revealed that this gene is localized in the vacuolar membrane. CsSWEET16 contributed to sugar compartmentation across the vacuole and function in modifying cold tolerance in Arabidopsis. Together, these findings demonstrate that CsSWEET genes play important roles in the response to abiotic and biotic stresses in tea plants and provide insights into the characteristics of SWEET genes in tea plants, which could serve as the basis for further functional identification of such genes. [ABSTRACT FROM AUTHOR]

The SWEET (sugars will eventually be exported transporters) proteins are sugar efflux transporters containing the MtN3_saliva domain, which affects plant development as well as responses to biotic and abiotic stresses. These proteins have not been functionally characterized in the tetraploid cotton, Gossypium hirsutum, which is a widely cultivated cotton species. In this study, we comprehensively analyzed the cotton SWEET gene family. A total of 55 putative G. hirsutum SWEET genes were identified. The GhSWEET genes were classified into four clades based on a phylogenetic analysis and on the examination of gene structural features. Moreover, chromosomal localization and an analysis of homologous genes in Gossypium arboreum, Gossypium raimondii, and G. hirsutum suggested that a whole-genome duplication, several tandem duplications, and a polyploidy event contributed to the expansion of the cotton SWEET gene family, especially in Clade III and IV. Analyses of cis-acting regulatory elements in the promoter regions, expression profiles, and artificial selection revealed that the GhSWEET genes were likely involved in cotton developmental processes and responses to diverse stresses. These findings may clarify the evolution of G. hirsutum SWEET gene family and may provide a foundation for future functional studies of SWEET proteins regarding cotton development and responses to abiotic stresses. [ABSTRACT FROM AUTHOR]

The orosensory characteristics of a diet play a role in its acceptance and rejection. The current study was designed to investigate the gustatory components that contribute to the intake of a palatable, high-energy diet (HE; 45% calories from fat, 17% calories from sucrose). Here, rats were conditioned to avoid HE diet by pairings with i.p. injections of LiCl to induce visceral malaise. Subsequently, the degree of generalization was tested to an array of taste compounds using a brief-access lick procedure (10-s trials, 30-min sessions). Compared to NaCl-injected controls, LiCl-injected rats suppressed licking response to 100% linoleic acid and 20% intralipid, and to a lesser extent 17% sucrose. There was more variability in the lick responses to sucrose among the LiCl-injected rats. Rats that tended to suppress licking responses to sucrose generalized this response to glucose, fructose and Na-saccharin but not to Polycose. In contrast, LiCl-injected rats did not significantly suppress lick responses to water, NaCl, citric acid, or quinine compared to controls rats. The brief access feature of this procedure, allows for behavioral measures when postingestive factors are minimized. These findings support a role for gustatory cues in the detection of high fat/high sugar diets. Furthermore, it appears that the fat component is a more salient orosensory feature of the HE diet. [ABSTRACT FROM AUTHOR]

The SWEET ( s ugars w ill e ventually be e xported t ransporter) family is a newly characterized group of sugar transporters. In plants, the key roles of SWEETs in phloem transport, nectar secretion, pollen nutrition, stress tolerance, and plant–pathogen interactions have been identified. SWEET family genes have been characterized in many plant species, but a comprehensive analysis of SWEET members has not yet been performed in wheat. Here, 59 wheat SWEETs (hereafter TaSWEETs) were identified through homology searches. Analyses of phylogenetic relationships, numbers of transmembrane helices (TMHs), gene structures, and motifs showed that TaSWEETs carrying 3–7 TMHs could be classified into four clades with 10 different types of motifs. Examination of the expression patterns of 18 SWEET genes revealed that a few are tissue-specific while most are ubiquitously expressed. In addition, the stem rust-mediated expression patterns of SWEET genes were monitored using a stem rust-susceptible cultivar, ‘Little Club’ (LC). The resulting data showed that the expression of five out of the 18 SWEETs tested was induced following inoculation. In conclusion, we provide the first comprehensive analysis of the wheat SWEET gene family. Information regarding the phylogenetic relationships, gene structures, and expression profiles of SWEET genes in different tissues and following stem rust disease inoculation will be useful in identifying the potential roles of SWEETs in specific developmental and pathogenic processes. [ABSTRACT FROM AUTHOR]

Recent studies in mice indicate that consumption of acesulfame K (a high intensity sweetener) while pregnant, can lead to deficits in taste or enhanced sweet consumption in the offspring, leading to concerns the same may be common in human populations. However, this work employed a relatively unpopular sweetener, fed in quantities amounting to over 20 × the FDA's Acceptable Daily Intake (ADI). The aims of this study were to test the effects of sucralose, the USA's most popular high intensity sweetener, along with sucrose, on the taste system of the offspring of mice supplemented at a level commensurate with ADIs while pregnant. The hypothesis was that feeding a dam intensely sweet solutions would produce offspring with enhanced response to sweet taste, when compared to offspring of dams given only water. Females were mated following a 4-week period in which one group was given a measured ration of sucrose or sucralose in addition to chow and water, with the control group given chow and water only. Sucrose and sucralose solutions were removed two weeks after parturition to prevent direct consumption by the offspring. The offspring at 8 weeks of age for both the sucrose and sucralose supplementation showed no change in their taste response to sucrose or sucralose. No effect of maternal sweet supplementation was detected at the taste bud level, with fungiform taste bud density and taste bud gene expression remaining unchanged. Overall, this study suggests that sucrose and sucralose consumption at human-relevant levels during pregnancy and lactation do not produce any long-term changes to the offspring's peripheral taste system. [ABSTRACT FROM AUTHOR]

Food preferences and dietary habits are heavily influenced by taste perception. There is growing interest in characterizing taste preferences based on genetic variation. Genetic differences in the ability to perceive key tastes may impact eating behavior and nutritional intake. Therefore, increased understanding of taste biology and genetics may lead to new personalized strategies, which may prevent or influence the trajectory of chronic disease risk. Recent advances show that single nucleotide polymorphisms (SNPs) in the CD36 fat taste receptor are linked to differences in fat perception, fat preference, and chronic-disease biomarkers. Genetic variation in the sweet taste receptor T1R2 has been shown to alter sweet taste preferences, eating behaviors, and risk of dental caries. Polymorphisms in the bitter taste receptor T2R38 have been shown to influence taste for brassica vegetables. Individuals that intensely taste the bitterness of brassica vegetables ("supertasters") may avoid vegetable consumption and compensate by increasing their consumption of sweet and fatty foods, which may increase risk for chronic disease. Emerging evidence also suggests that the role of genetics in taste perception may be more impactful in children due to the lack of cultural influence compared to adults. This review examines the current knowledge of SNPs in taste receptors associated with fat, sweet, bitter, umami, and salt taste modalities and their contributions to food preferences, and chronic disease. Overall, these SNPs demonstrate the potential to influence food preferences and consequently health. [ABSTRACT FROM AUTHOR]

Summary: As waterlogging and successive events severely influence growth and development of economically important plants, we attempted to characterize the role of a waterlogging‐responsive group I (A‐6) ethylene response factor (MaRAP2‐4) from Mentha arvensis. Waterlogging, ethylene and methyl jasmonate rapidly induced the expression of MaRAP2‐4. MaRAP2‐4 interacted with multiple cis‐elements like dehydration response elements (DRE1/2), anoxia/jasmonic acid response element (JARE) and GCC box showing its involvement in multiple responses. MaRAP2‐4 localizes in the nucleus and acts as a transcriptional activator. Truncation and internal deletion identified a 20 amino acids potential transactivation domain (PLPSSVDAKLEAICQSLAIN) in MaRAP2‐4. MaRAP2‐4 transgenic Arabidopsis showed enhanced waterlogging and subsequent oxidative stress tolerance. Microarray analysis revealed that within up‐regulated genes 483, 212 and 132 promoters carry either single or multiple copies of DRE, JARE and GCC cis‐element/s, respectively. Within these promoters, a large section belongs to carbohydrate metabolism/transport, including many SWEET transporters. Further analysis showed MaRAP2‐4 specifically targets two positions in AtSWEEET10 promoter carrying DRE and/or GCC box that might regulate carbohydrate availability and waterlogging tolerance. These results demonstrate that MaRAP2‐4 is a positive regulator of waterlogging tolerance, and as energy‐consuming processes such as carbohydrate biosynthesis are reduced under waterlogging‐induced hypoxia, sugar transport through SWEETs may be the primary option to make sugar available to the required tissue. [ABSTRACT FROM AUTHOR]

Flavorants such as lemon extract that activate olfactory receptors may also evoke or enhance flavor qualities such as sour and sweet that are typically considered gustatory. Similarly, flavorants such as sucrose and citric acid that activate gustatory receptors may enhance flavors such as citrus that are typically considered olfactory. Here, we ask how lemon extract, sucrose, and citric acid, presented separately and together, affect sweet, sour, and citrus flavors. We accomplished this by testing, in the same 12 subjects, lemon extract and sucrose (Experiment 1), lemon extract and citric acid (Experiment 2), and lemon extract, sucrose, and citric acid (Experiment 3). Results showed that both lemon extract and citric acid increased the ratings of citrus and sour intensity. Lemon extract did not affect sweet, but citric acid did, mainly in Experiment 3. Sucrose systematically increased only sweet intensity and modulated the effect of lemon extract on sour. The most robust multiquality effect was the enhancement of sour by lemon extract. These outcomes suggest, first, a role played by experience with the statistical associations of gustatory and olfactory flavorants and, second, that lemon flavor is complex, having citrus and sour qualities that may not be fully separable in perception. [ABSTRACT FROM AUTHOR]

Responses to sweetness are reported in two populations, one segmented by gender and age, and the other one by gender only. The strength of the association between liking for specific sweet foods and liking for an aqueous sucrose solution (20% w/v) is also tested, and health attitudes examined. British adults (n = 1855, age 17–82, mean 55 years, 90% women) and Finnish young adults (n = 1292, age 20–25, mean 22 years, 54% women) rated their liking of ten sweet foods and beverages based on product names, and completed questionnaires on Craving for Sweet Foods (CSF) and General Health Interest (GHI). One-half of Brits and a third of Finns rated liking and intensity of sucrose solution. In factor analysis, identical categories of liking for sweet products were formed in each population, one consisting of five processed sweets (“Goodies”), and the other of naturally sweet fruits and berries (“Fruits”). Sugared and sugar-free s oft drinks and fruit juice loaded on the third factor. After age 50, British men scored higher than British women in CSF and liking for several sweet products; Finnish women scored higher than Finnish men in CSF and liking for most sweet products. GHI was positively associated with liking for Fruits and negatively with liking for sugared soft drinks. Sucrose solution was better liked by British men than women, with no gender difference in Finns. Liking for sucrose solution was only weakly associated with liking for sweet products based on product names. In two demographically different European populations, attraction to sweet gathered in similar product categories, but manifested differently at different ages and each gender. [ABSTRACT FROM AUTHOR]

Children generally have a high acceptance for sweetness, but differ in their preferences for the intensity of the taste. This study investigates how food exposure, parental attitudes and behaviours, and children’s taste sensitivity are associated with five-year olds’ preferences for sweetness. Preference data were collected from 135 children at ages four (Mean age: 46.3 months, SD: 3.4, 56% boys) and five years old (Mean age: 57.5 months, SD: 3.3; 58% boys) in a ranking by elimination procedure in the springs of 2015 and 2016. The taste carriers were fruit-flavoured beverages and dark chocolate, both with three levels of sugar content. Quantitative descriptive analysis testified three distinct levels of sweetness in each sample triad. The same children were also tested for sweetness and bitterness taste sensitivity in a paired comparison procedure. The protocols did not require the children to respond verbally, and included elements of gamification in order to engage the children. In addition, a parental questionnaire enquired about exposure to different foods, parental food attitudes and behaviours as well as socio-demographic characteristics. Path modelling using PLS-SEM indicated that differences in children’s preference for sweetness could be explained by differences in exposure to foods, including more frequent exposure to sweet foods and snacks associated with a higher sweet preference. More frequent exposure to fruit and bitter snacks, were associated with a lower sweet preference for the drink and chocolate, respectively. Parental attitudes and behaviours as well as children’s sensitivity to sweetness and bitterness were significantly associated with what foods the children were frequently exposed to, and to their sweetness preferences in beverages and chocolate. [ABSTRACT FROM AUTHOR]

SWEET proteins play an indispensable role as a sugar efflux transporter in plant development and stress responses. The SWEET genes have previously been characterized in several plants. Here, we present a comprehensive analysis of this gene family in the rubber tree, Hevea brasiliensis. There are 36 members of the SWEET gene family in this species, making it one of the largest families in plant genomes sequenced so far. Structure and phylogeny analyses of these genes in Hevea and in other species demonstrated broad evolutionary conservation. RNA-seq analyses revealed that SWEET2, 16, and 17 might represent the main evolutionary direction of SWEET genes in plants. Our results in Hevea suggested the involvement of HbSWEET1a, 2e, 2f, and 3b in phloem loading, HbSWEET10a and 16b in laticifer sugar transport , and HbSWEET9a in nectary-specific sugar transport. Parallel studies of RNA-seq analyses extended to three other plant species ( Manihot esculenta, Populus trichocarpa, and Arabidopsis thaliana) produced findings which implicated MeSWEET10a, 3a, and 15b in M. esculenta storage root development, and the involvement of PtSWEET16b and PtSWEET16d in P. trichocarpa xylem development. RT-qPCR results further revealed that HbSWEET10a, 16b, and 1a play important roles in phloem sugar transport. The results from this study provide a foundation not only for further investigation into the functionality of the SWEET gene family in Hevea, especially in its sugar transport for latex production, but also for related studies of this gene family in the plant kingdom. [ABSTRACT FROM AUTHOR]

The plant SWEET family is a sugar transporter family that plays a significant role in plant development. Here, seven loquat SWEET family members were identified by RNA-seq. These were designated as EjSWEET1, EjSWEET2a, EjSWEET2b, EjSWEET2c, EjSWEET4, EjSWEET15, and EjSWEET17. Phylogenetic and predictive functional annotation analyses suggest that the loquat SWEETs are classified as having sucrose, glucose and fructose transportation features. The in vivo responses of loquat SWEETs to exogenous sugar or NaCl was investigated by applying high concentrations of sugar or salt to 7-month-old loquat seedlings cultured in a nutrient medium. The results showed that most loquat SWEET genes can respond to exogenous applications of sucrose, glucose, fructose and salt. The response of EjSWEET1 to exogenous fructose was faster than the others, indicating that EjSWEET1 is more sensitive to exogenous fructose compared with other loquat SWEETs. EjSWEET15 can be induced by sucrose, but is suppressed by glucose. This indicates its possible role in sucrose transporting. The response of loquat SWEETs to NaCl showed broadly similar patterns compared to sugars. However, after a longer time of NaCl treatment, most loquat SWEETs are upregulated, especially EjSWEET15. This indicates its long-term response to high salinity. [ABSTRACT FROM AUTHOR]

Children and adolescents are the highest consumers of added sugars, particularly from sugar-sweetened beverages (SSB). Regular consumption of SSB early in life induces a variety of negative consequences on health that can last into adulthood. Low-calorie sweeteners (LCS) are increasingly used as an alternative to added sugars because they provide a sweet sensation without adding calories to the diet. However, the long-term effects of early-life consumption of LCS are not well understood. Considering LCS engage at least one of the same taste receptors as sugars and potentially modulate cellular mechanisms of glucose transport and metabolism, it is especially important to understand how early-life LCS consumption impacts intake of and regulatory responses to caloric sugars. In our recent study, we found that habitual intake of LCS during the juvenile-adolescence period significantly changed how rats responded to sugar later in life. Here, we review evidence that LCS and sugars are sensed via common and distinct gustatory pathways, and then discuss the implications this has for shaping sugar-associated appetitive, consummatory, and physiological responses. Ultimately, the review highlights the diverse gaps in knowledge that will be necessary to fill to understand the consequences of regular LCS consumption during important phases of development. [ABSTRACT FROM AUTHOR]