Metabolic and transcriptomic analyses of nectaries reveal differences in the mechanism of nectar production between monocots (Ananas comosus) and dicots (Nicotiana tabacum).

BACKGROUND: Nectar is offered by numerous flowering plants to attract pollinators. To date, the production and secretion of nectar have been analyzed mainly in eudicots, particularly rosids such as Arabidopsis. However, due to the enormous diversity of flowering plants, further research on other plant species, especially monocots, is needed. Ananas comosus (monocot) is an economically important species that is ideal for such analyses because it produces easily accessible nectar in sufficient quantities. In addition, the analyses were also carried out with Nicotiana tabacum (dicot, asterids) for comparison. RESULTS: We performed transcriptome sequencing (RNA-Seq) analyses of the nectaries of Ananas comosus and Nicotiana tabacum, to test whether the mechanisms described for nectar production and secretion in Arabidopsis are also present in these plant species. The focus of these analyses is on carbohydrate metabolism and transport (e.g., sucrose-phosphate synthases, invertases, sucrose synthases, SWEETs and further sugar transporters). In addition, the metabolites were analyzed in the nectar, nectaries and leaves of both plant species to address the question of whether concentration gradients for different metabolites exist between the nectaries and nectar The nectar of N. tabacum contains large amounts of glucose, fructose and sucrose, and the sucrose concentration in the nectar appears to be similar to the sucrose concentration in the nectaries. Nectar production and secretion in this species closely resemble corresponding processes in some other dicots, including sucrose synthesis in nectaries and sucrose secretion by SWEET9. The nectar of A. comosus also contains large amounts of glucose, fructose and sucrose and in this species the sucrose concentration in the nectar appears to be higher than the sucrose concentration in the nectaries. Furthermore, orthologs of SWEET9 generally appear to be absent in A. comosus and other monocots. Therefore, sucrose export by SWEETs from nectaries into nectar can be excluded; rather, other mechanisms, such as active sugar export or exocytosis, are more likely. CONCLUSION: The mechanisms of nectar production and secretion in N. tabacum appear to be largely similar to those in other dicots, whereas in the monocotyledonous species A. comosus, different synthesis and transport processes are involved.

The association between junk foods consumption and attention deficit hyperactivity disorder in children and adolescents: a systematic review and meta-analysis of observational studies.

The adverse effects of junk foods on the risk of attention deficit hyperactivity disorder (ADHD) symptoms were reported in several studies. In this meta-analysis, the association between junk food consumption and the risk of ADHD was investigated in children and adolescents. A comprehensive systematic search was conducted to find all relevant literature via four databases, including PubMed, Web of Science, Scopus, and Google scholar, up to September 2022. Two independent authors screened all documents based on inclusion criteria. The overall effect sizes and related 95% confidence interval (CI) were pooled with the random effect approach. Subgroup analysis was done to measure potential sources of heterogeneity between studies. The quality of the included studies was evaluated with The Newcastle-Ottawa scale (NOS). Nine observational studies with 58,296 children /adolescents were eligible to be include in the meta-analysis. According to the random effect model, there was a positive relation between the consumption of junk foods and ADHD symptoms (odds ratio (OR): 1.24, 95%CI 1.15-1.34, P < 0.001, I2: 37.4%, P = 0.085). A similar significant positive association was shown in the subgroups analysis by different junk foods (sweetened beverages/soft drinks, sweets/candies, and other types of junk foods). This meta-analysis finding demonstrated that consuming junk foods, especially sweetened beverages/soft drinks, and sweets/candies is associated with ADHD symptoms.

Genome-wide analysis of the SWEET gene family in Hemerocallis citrina and functional characterization of HcSWEET4a in response to salt stress.

Sugars will be eventually effluxed transporters (SWEETs) have been confirmed to play diverse physiological roles in plant growth, development and stress response. However, the characteristics and functions of the SWEET genes in Hemerocallis citrina remain unclear and poorly elucidated. In this study, the whole genome of Hemerocallis citrina was utilized to conduct bioinformatics analysis and a total of 19 HcSWEET genes were successfully identified. Analysis of the physicochemical properties indicated dominant differences among these HcSWEETs. A phylogenetic analysis revealed that HcSWEET proteins can be divided into 4 clades ranging from Clade I to IV, where proteins within the same clade exhibited shared conserved motifs and gene structures. Five to six exons were contained in the majority of HcSWEET genes, which were unevenly distributed across 11 chromosomes. The gene duplication analysis showed the presence of 4 gene pairs. Comparative syntenic maps revealed that the HcSWEET gene family might present more closed homology in monocotyledons than dicotyledons. Cis-acting element analysis of HcSWEET genes indicated key responsiveness to various hormones, light, and stresses. Additionally, transcriptome sequencing analysis suggested that most HcSWEET genes had a relatively higher expression in roots, and HcSWEET4a was significantly up-regulated under salt stress. Overexpression further verified the possibility that HcSWEET4a was involved in response to salt stress, which provides novel insights and facilitates in-depth studies of the functional analysis of HcSWEETs in resistance to abiotic stress.

Targeted protein degradation systems to enhance Wnt signaling.

Molecules that facilitate targeted protein degradation (TPD) offer great promise as novel therapeutics. The human hepatic lectin asialoglycoprotein receptor (ASGR) is selectively expressed on hepatocytes. We have previously engineered an anti-ASGR1 antibody-mutant RSPO2 (RSPO2RA) fusion protein (called SWEETS) to drive tissue-specific degradation of ZNRF3/RNF43 E3 ubiquitin ligases, which achieved hepatocyte-specific enhanced Wnt signaling, proliferation, and restored liver function in mouse models, and an antibody-RSPO2RA fusion molecule is currently in human clinical trials. In the current study, we identified two new ASGR1- and ASGR1/2-specific antibodies, 8M24 and 8G8. High-resolution crystal structures of ASGR1:8M24 and ASGR2:8G8 complexes revealed that these antibodies bind to distinct epitopes on opposing sides of ASGR, away from the substrate-binding site. Both antibodies enhanced Wnt activity when assembled as SWEETS molecules with RSPO2RA through specific effects sequestering E3 ligases. In addition, 8M24-RSPO2RA and 8G8-RSPO2RA efficiently downregulate ASGR1 through TPD mechanisms. These results demonstrate the possibility of combining different therapeutic effects and degradation mechanisms in a single molecule.

Associations of Eating Habits with Self-Rated Health and Life Satisfaction in Adolescents: A 42-Country Cross-Sectional Study.

OBJECTIVE: The aim of this study was to explore the associations of eating habits with self-rated health and life satisfaction in adolescents using a multiple-country sample. METHODS: Cross-sectional data from the Health Behavior in School-Aged Children (HBSC) 2013/2014 wave was used in this study. A self-reported questionnaire was used to collect data on independent variables including breakfast on weekdays, breakfast at weekends, and consumption of fruits, vegetables, sweets, and soft dirks. Outcomes included self-rated health and life satisfaction. Regression models were used to assess the associations between the independent variables and the two outcomes, separately, after controlling for covariates. Results were presented using odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Of all the study participants (aged 11-15 years), 50.8% were girls. Compared with no consumption of breakfast on weekdays, eating breakfast for five days had 1.22 times greater likelihood for improved self-rated health (OR = 1.22, 95% CI: 1.19-1.25, p < 0.001). Participants who ate breakfast for both days (OR = 1.41, 95% CI: 1.36-1.46, p < 0.001) and one day (OR = 1.12, 95% CI = 1.08-1.17, p < 0.001) were more likely to experience improved self-rated health compared to never eating breakfast at weekends. Five or more days for fruit and vegetable consumption resulted in better self-rated health (all p < 0.001). Similar results were found in terms of the associations of breakfast, fruit, and vegetable consumption with life satisfaction. For example, a higher frequency of fruit intake was associated with enhanced self-rated health (e.g., OR for more than once daily = 1.42, 95% CI: 1.34-1.51, p < 0.001) compared to no fruit consumption. Similarly, a higher-frequency vegetable intake, such as more than once daily (OR = 1.33, 95% CI: 1.26-1.39, p < 0.001), was associated with improved self-rated health. CONCLUSIONS: Healthy eating habits, especially regular breakfast and a higher consumption of vegetables and fruit, are associated with better self-rated health and life satisfaction in school-aged children. Of note, the consumption of fruit would have the greatest impact on health and wellbeing outcomes. This study offers evidence that healthy eating habits can play a vital role in school-aged children's health and wellbeing, highlighting the practical significance of educating adolescents to develop healthy eating habits.

Potato E3 ubiquitin ligase StRFP1 positively regulates late blight resistance by degrading sugar transporters StSWEET10c and StSWEET11.

Potato (Solanum tuberosum) is the fourth largest food crop in the world. Late blight, caused by oomycete Phytophthora infestans, is the most devastating disease threatening potato production. Previous research has shown that StRFP1, a potato Arabidopsis Tóxicos en Levadura (ATL) family protein, positively regulates late blight resistance via its E3 ligase activity. However, the underlying mechanism is unknown. Here, we reveal that StRFP1 is associated with the plasma membrane (PM) and undergoes constitutive endocytic trafficking. Its PM localization is essential for inhibiting P. infestans colonization. Through in vivo and in vitro assays, we investigated that StRFP1 interacts with two sugar transporters StSWEET10c and StSWEET11 at the PM. Overexpression (OE) of StSWEET10c or StSWEET11 enhances P. infestans colonization. Both StSWEET10c and StSWEET11 exhibit sucrose transport ability in yeast, and OE of StSWEET10c leads to an increased sucrose content in the apoplastic fluid of potato leaves. StRFP1 ubiquitinates StSWEET10c and StSWEET11 to promote their degradation. We illustrate a novel mechanism by which a potato ATL protein enhances disease resistance by degrading susceptibility (S) factors, such as Sugars Will Eventually be Exported Transporters (SWEETs). This offers a potential strategy for improving disease resistance by utilizing host positive immune regulators to neutralize S factors.

Nutritional status changes in the treatment of substance use disorder: Relationship with substance craving.

Tailored nutrition counseling enhances the efficacy of routine treatment for substance (alcohol/drugs) use disorders (SUDs). For this purpose, it is important to understand the current nutritional status of addicts and the changes in their nutritional status during the treatment process. Furthermore, the consumption of sweets to manage substance cravings is common among people with SUDs, but the evidence for the effectiveness of this practice is limited and conflicting. We therefore hypothesized SUD treatment would be associated with increases in appetite, nutrient intake, and anthropometric measurements in addicts, and that these changes, including changes in sweet consumption, would not be associated with decreased substance craving. Data for this prospective observational study were collected from 38 adult male patients who completed 21 days of inpatient SUD treatment. During the treatment, the participants' levels of appetite (P < 1.0 × 10-4), the frequency of main meals (P < 1.0 × 10-4), intake of macro- and micronutrients (P < .05 for each), and anthropometric measurements (P ≤ 5.9 × 10-4), significantly increased. Furthermore, it was found that the patients had a significant increase in sweets craving (P < 1.0 × 10-4) and sweets consumption (P = 1.2 × 10-3) during treatment. However, there was no significant difference between the individuals whose craving decreased and those whose craving did not decrease at the end of the treatment (P > .05 for both). The findings suggest the need to offer dietary counseling to individuals undergoing inpatient SUD treatment, given the substantial changes in nutritional status, and that increased consumption of sweets is not an effective strategy to reduce substance craving.

Orchids acquire fungal carbon for seed germination: pathways and players.

To germinate in nature, orchid seeds strictly rely on seed germination-promoting orchid mycorrhizal fungi (sgOMFs) for provision of carbon nutrients. The underlying delivery pathway, however, remains elusive. We develop here a plausible model for sugar transport from sgOMFs to orchid embryonic cells to fuel germination. Orchids exploit sgOMFs to induce the formation of pelotons, elaborate intracellular hyphal coils in orchid embryos. The colonized orchid cells then obtain carbon nutrients by uptake from living hyphae and peloton lysis, primarily as glucose derived from fungal trehalose hydrolyzed by orchid-specific trehalases. The uptake of massive fungally derived glucose is likely to be mediated by two classes of membrane proteins, namely, sugars will eventually be exported transporters (SWEETs) and H+-hexose symporters. The proposed model serves as a launch pad for further research to better understand and improve orchid seed germination and conservation.

Substrate selectivity and unique sequence signatures in SWEET/semiSWEET homologs of four taxonomic groups: Sequence analysis and phylogenetic studies.

The recently discovered SWEET (Sugar Will Eventually be Exported Transporter) proteins are involved in the selective transport of monosaccharides and disaccharides. The prokaryotic counterparts, semiSWEETs, form dimers with each monomer forming a triple-helix transmembrane bundle (THB). The longer eukaryotic SWEETs have seven transmembrane helices with two THBs and a linker helix. Structures of semiSWEETs/SWEETs have been determined experimentally. Experimental studies revealed the role of plant SWEETs in vital physiological processes and identified residues responsible for substrate selectivity. However, SWEETs/semiSWEETs from metazoans and bacteria are not characterized. In this study, we used structure-based sequence alignment and compared more than 2000 SWEET/semiSWEETs from four different taxonomic groups. Conservation of residue/chemical property was examined at all positions. Properties of clades/subclades of phylogenetic trees from each taxonomic group were analyzed. Conservation pattern of known residues in the selectivity-filter was used to predict the substrate preference of plant SWEETs and some clusters of metazoans and bacteria. Some residues at the gating and substrate-binding regions, pore-facing positions and at the helix-helix interface are conserved across all taxonomic groups. Conservation of polar/charged residues at specific pore-facing positions, helix-helix interface and in loops seems to be unique for plant SWEETs. Overall, the number of conserved residues is less in metazoan SWEETs. Plant and metazoan SWEETs exhibit high conservation of four and three proline residues respectively in "proline tetrad." Further experimental studies can validate the predicted substrate selectivity and significance of conserved polar/charged/aromatic residues at structurally and functionally important positions of SWEETs/semiSWEETs in plants, metazoans and bacteria.

Sugar accumulation enhancement in sorghum stem is associated with reduced reproductive sink strength and increased phloem unloading activity.

Sweet sorghum has emerged as a promising source of bioenergy mainly due to its high biomass and high soluble sugar yield in stems. Studies have shown that loss-of-function Dry locus alleles have been selected during sweet sorghum domestication, and decapitation can further boost sugar accumulation in sweet sorghum, indicating that the potential for improving sugar yields is yet to be fully realized. To maximize sugar accumulation, it is essential to gain a better understanding of the mechanism underlying the massive accumulation of soluble sugars in sweet sorghum stems in addition to the Dry locus. We performed a transcriptomic analysis upon decapitation of near-isogenic lines for mutant (d, juicy stems, and green leaf midrib) and functional (D, dry stems and white leaf midrib) alleles at the Dry locus. Our analysis revealed that decapitation suppressed photosynthesis in leaves, but accelerated starch metabolic processes in stems. SbbHLH093 negatively correlates with sugar levels supported by genotypes (DD vs. dd), treatments (control vs. decapitation), and developmental stages post anthesis (3d vs.10d). D locus gene SbNAC074A and other programmed cell death-related genes were downregulated by decapitation, while sugar transporter-encoding gene SbSWEET1A was induced. Both SbSWEET1A and Invertase 5 were detected in phloem companion cells by RNA in situ assay. Loss of the SbbHLH093 homolog, AtbHLH093, in Arabidopsis led to a sugar accumulation increase. This study provides new insights into sugar accumulation enhancement in bioenergy crops, which can be potentially achieved by reducing reproductive sink strength and enhancing phloem unloading.

Camellia oleifera CoSWEET10 Is Crucial for Seed Development and Drought Resistance by Mediating Sugar Transport in Transgenic Arabidopsis.

Sugar transport from the source leaf to the sink organ is critical for seed development and crop yield, as well as for responding to abiotic stress. SWEETs (sugar will eventually be exported transporters) mediate sugar efflux into the reproductive sink and are therefore considered key candidate proteins for sugar unloading during seed development. However, the specific mechanism underlying the sugar unloading to seeds in Camellia oleifera remains elusive. Here, we identified a SWEET gene named CoSWEET10, which belongs to Clade III and has high expression levels in the seeds of C. oleifera. CoSWEET10 is a plasma membrane-localized protein. The complementation assay of CoSWEET10 in SUSY7/ura3 and EBY.VW4000 yeast strains showed that CoSWEET10 has the ability to transport sucrose, glucose, and fructose. Through the C. oleifera seeds in vitro culture, we found that the expression of CoSWEET10 can be induced by hexose and sucrose, and especially glucose. By generating the restoration lines of CoSWEET10 in Arabidopsis atsweet10, we found that CoSWEET10 restored the seed defect phenotype of the mutant by regulating soluble sugar accumulation and increased plant drought tolerance. Collectively, our study demonstrates that CoSWEET10 plays a dual role in promoting seed development and enhancing plant drought resistance as a sucrose and hexose transporter.

High intake of sweet foods and low life satisfaction can act as risk factors for acute coronary syndrome through synergistic interaction.

Purpose: Dietary and psychological status contributes to the development of coronary artery disease. However, these lifestyle factors may vary depending on ethnic and environmental background, and secondary prevention programs dealing with these factors in a specific population are not well-established. We aimed to assess dietary and psychological characteristics in Korean patients with acute coronary syndrome (ACS) and analyze their interactions as independent risk factors for ACS. Methods: Ninety-two patients with ACS (29 acute myocardial infarction and 63 unstable angina) and 69 controls were subjected to dietary and psychological analyses. Dietary intake was assessed by a food frequency questionnaire. Psychological depression and perceived stress were assessed using the Patient Health Questionnaire-9 and the Perceived Stress Scale, respectively. Eight domains of life satisfaction (marital/love relationship, leisure, standard of living, job, health, family life, sex life, and self) were assessed using the Domain Satisfaction Questionnaire (DSQ). Results: The ACS group had a higher consumption of sweets and fish/seafood, as well as higher levels of depressive symptoms. Additionally, they had lower DSQ scores in total, and all eight individual domains compared with the control group. In multivariate logistic regression analysis, sweet intake (OR 4.57, 95% CI: 1.94-11.40) and total DSQ scores (OR 0.34, 95% CI: 0.14-0.81) were identified as independent risk factors for ACS. Furthermore, these factors, which displayed a significant inverse correlation (ρ = -0.23, p = 0.01), were determined as having a synergistic contribution to the development of ACS. Conclusion: High sweet food intake and low life satisfaction can act as risk factors for ACS through a synergistic interaction, which emphasizes a demand for a more comprehensive approach to secondary prevention of ACS. In addition, these data highlight the role of positive psychological wellbeing factors in cardiovascular health.

Identification and expression analysis of the SWEET genes in radish reveal their potential functions in reproductive organ development.

BACKGROUND: Sugars produced by photosynthesis provide energy for biological activities and the skeletons for macromolecules; they also perform multiple physiological functions in plants. Sugar transport across plasma membranes mediated by the Sugar Will Eventually be Exported Transporter (SWEET) genes substantially affects these processes. However, the evolutionary dynamics and function of the SWEET genes are largely unknown in radish, an important Brassicaceae species. METHODS AND RESULTS: Genome-wide identification and analysis of the RsSWEET genes from the recently updated radish reference genome was conducted using bioinformatics methods. The tissue-specific expression was analyzed using public RNA-seq data, and the expression levels in the bud, stamens, pistils, pericarps and seeds at 15 and 30 days after flowering (DAF) were determined by RT‒qPCR. Thirty-seven RsSWEET genes were identified and named according to their Arabidopsis homologous. They are unevenly distributed across the nine radish chromosomes and were further divided into four clades by phylogenetic analysis. There are 5-7 transmembrane domains and at least one MtN3_slv domain in the RsSWEETs. RNA-seq and RT‒qPCR revealed that the RsSWEETs exhibit higher expression levels in the reproductive organs, indicating that these genes might play vital roles in reproductive organ development. RsSWEET15.1 was found to be especially expressed in siliques according to the RNA-seq data, and the RT‒qPCR results further confirmed that it was most highly expressed levels in the seeds at 30 DAF, followed by the pericarp at 15 DAF, indicating that it is involved in seed growth and development. CONCLUSIONS: This study suggests that the RsSWEET genes play vital roles in reproductive organ development and provides a theoretical basis for the future functional analysis of RsSWEETs in radish.

Associations between vitamin D levels and dietary patterns in patients with Hashimoto's thyroiditis.

Introduction: Vitamin D insufficiency is a global health problem affecting healthy and diseased individuals, including patients with Hashimoto's thyroiditis (HT). Identifying dietary factors that may affect vitamin D levels and providing dietary guidelines accordingly can alleviate this problem. We therefore aimed to identify still unknown associations of dietary patterns, assessed through the Food Frequency Questionnaire (FFQ) with vitamin D blood levels. Materials and methods: FFQ was collected from 459 patients from Croatian Biobank of Patients with Hashimoto's thyroiditis (CROHT), while total 25(OH)D was measured from their stored serum samples. We performed linear regression analysis between vitamin D levels and weekly intake of 24 food groups in 459 patients with HT (ALL), and in two disease-severity groups (MILD and OVERT). Results: The main results of our study are observations of: (1) an inverse association between vitamin D levels and coffee consumption (ALL: ß = -0.433, p = 0.005; OVERT: ß = -0.62, p = 0.008); (2) an inverse association between vitamin D levels and sweets consumption (ALL: ß = -0.195, p = 0.034; OVERT: ß = -0.431, p = 0.006); (3) positive association between vitamin D levels and vegetable consumption (ALL: ß = 0.182, p = 0.019; OVERT, ß = 0.311, p = 0.009). Importantly, effect sizes of all three associations were more prominent in HT patients with prolonged and more severe disease (OVERT). Conclusion: Further research into the functional and causal relationships of the observed associations is important to provide guidance regarding coffee/sugar intake on vitamin D status. A well-balanced diet can help prevent vitamin D deficiency and improve the quality of life of patients with HT, especially those in later stages of disease characterized by greater metabolic imbalance.

Integrated Metabolomic and Transcriptomic Analyses Reveals Sugar Transport and Starch Accumulation in Two Specific Germplasms of Manihot esculenta Crantz.

As a starchy and edible tropical plant, cassava (Manihot esculenta Crantz) has been widely used as an industrial raw material and a dietary source. However, the metabolomic and genetic differences in specific germplasms of cassava storage root were unclear. In this study, two specific germplasms, M. esculenta Crantz cv. sugar cassava GPMS0991L and M. esculenta Crantz cv. pink cassava BRA117315, were used as research materials. Results showed that sugar cassava GPMS0991L was rich in glucose and fructose, whereas pink cassava BRA117315 was rich in starch and sucrose. Metabolomic and transcriptomic analysis indicated that sucrose and starch metabolism had significantly changing metabolites enrichment and the highest degree of differential expression genes, respectively. Sugar transport in storage roots may contribute to the activities of sugar, which will eventually be exported to transporters (SWEETs), such as (MeSWEET1a, MeSWEET2b, MeSWEET4, MeSWEET5, MeSWEET10b, and MeSWEET17c), which transport hexose to plant cells. The expression level of genes involved in starch biosynthesis and metabolism were altered, which may result in starch accumulation. These results provide a theoretical basis for sugar transport and starch accumulation and may be useful in improving the quality of tuberous crops and increasing yield.

Metabolic and Dietary Factors in Acne Vulgaris and Evaluation of the Acne Vulgaris Treatment with Oral Contraceptive-Based Therapies in Young Adult Women.

The etiopathogenesis of acne is complex, as several endo- and exogenous factors that affect the sebaceous-hair unit are involved in the development of acne lesions. The main aim of the study was to evaluate selected metabolic parameters before treatment. Another goal of the study was to determine the correlation between selected metabolic and dietary parameters and the severity of acne before treatment. The third objective was to assess the severity of acne before and after treatment, considering the type of treatment used. The final objective was to assess the relationship between the difference in acne severity before and after treatment, considering the type of treatment used and factors of dairy or sweets intake. 168 women participated in the study. The patients belonged to two groups: the study group (99 patients with acne vulgaris) and the control group (69 patients without skin lesions). The study group was divided into subgroups according to the treatment used: contraceptive preparation, contraceptive preparation and cyproterone acetate, and contraceptive preparation and isotretinoin preparation. We found that LDL levels and consumption of sweets correlated with acne severity. The mainstay of acne treatment is contraceptive treatment (ethinylestradiol and drospirenone). The effectiveness of the three contraceptive-based treatments was confirmed by observing the severity of acne. There were no significant correlations between the difference in acne severity before and after treatment with the three treatments and factors of dairy or sweet consumption.

Population Structure and Association Mapping for Agronomical and Biochemical Traits of a Large Spanish Apple Germplasm.

A basic knowledge of linkage disequilibrium and population structure is necessary in order to determine the genetic control and identify significant associations with agronomical and phytochemical compounds in apple (Malus × domestica Borkh). In this study, 186 apple accessions (Pop1), representing both Spanish native accessions (94) and non-Spanish cultivars (92) from the EEAD-CSIC apple core collection, were assessed using 23 SSRs markers. Four populations were considered: Pop1, Pop2, Pop3, and Pop4. The initial Pop1 was divided into 150 diploid (Pop2) and 36 triploid accessions (Pop3), while for the inter-chromosomal linkage disequilibrium and the association mapping analysis, 118 phenotype diploid accessions were considered Pop4. Thus, the average number of alleles per locus and observed heterozygosity for the overall sample set (Pop1) were 15.65 and 0.75, respectively. The population structure analysis identified two subpopulations in the diploid accessions (Pop2 and Pop4) and four in the triploids (Pop3). Regarding the Pop4, the population structure with K = 2 subpopulations segregation was in agreement with the UPGMA cluster analysis according to the genetic pairwise distances. Moreover, the accessions seemed to be segregated by their origin (Spanish/non-Spanish) in the clustering analysis. One of the two subpopulations encountered was quite-exclusively formed by non-Spanish accessions (30 out of 33). Furthermore, agronomical and basic fruit quality parameters, antioxidant traits, individual sugars, and organic acids were assessed for the association mapping analysis. A high level of biodiversity was exhibited in the phenotypic characterization of Pop4, and a total of 126 significant associations were found between the 23 SSR markers and the 21 phenotypic traits evaluated. This study also identified many new marker-locus trait associations for the first time, such as in the antioxidant traits or in sugars and organic acids, which may be useful for predictions and for a better understanding of the apple genome.

Rhizoctonia solani transcriptional activator interacts with rice WRKY53 and grassy tiller 1 to activate SWEET transporters for nutrition.

INTRODUCTION: Rhizoctonia solani, the causative agent of the sheath blight disease (ShB), invades rice to obtain nutrients, especially sugars; however, the molecular mechanism via which R. solani hijacks sugars from rice remains unclear. OBJECTIVES: In this study, rice-R. solani interaction model was used to explore whether pathogen effector proteins affect plant sugar absorption during infection. METHODS: Yeast one-hybrid assay was used to identify Activator of SWEET2a (AOS2) from R. solani. Localization and invertase secretion assays showed that nuclear localization and secreted function of AOS2. Hexose transport assays verified the hexose transporter activity of SWEET2a and SWEET3a. Yeast two-hybrid assays, Bimolecular fluorescence complementation (BiFC) and transactivation assay were conducted to verify the AOS2-WRKY53-Grassy tiller 1 (GT1) transcriptional complex and its activation of SWEET2a and SWEET3a. Genetic analysis is used to detect the response of GT1, WRKY53, SWEET2a, and SWEET3a to ShB infestation. Also, the soluble sugar contents were measured in the mutants and overexpression plants before and after the inoculation of R. solani. RESULTS: The present study found that R. solani protein AOS2 activates rice SWEET2a and localized in the nucleus of tobacco cells and secreted in yeast. AOS2 interacts with rice transcription factor WRKY53 and GT1 to form a complex that activates the hexose transporter gene SWEET2a and SWEET3a and negatively regulate rice resistance to ShB. CONCLUSION: These data collectively suggest that AOS2 secreted by R. solani interacts with rice WRKY53 and GT1 to form a transcriptional complex that activates SWEETs to efflux sugars to apoplast; R. solani acquires more sugars and subsequently accelerates host invasion.

Physiological implications of SWEETs in plants and their potential applications in improving source-sink relationships for enhanced yield.

The sugars will eventually be exported transporters (SWEET) family of transporters in plants is identified as a novel class of sugar carriers capable of transporting sugars, sugar alcohols and hormones. Functioning in intercellular sugar transport, SWEETs influence a wide range of physiologically important processes. SWEETs regulate the development of sink organs by providing nutritional support from source leaves, responses to abiotic stresses by maintaining intracellular sugar concentrations, and host-pathogen interactions through the modulation of apoplastic sugar levels. Many bacterial and fungal pathogens activate the expression of SWEET genes in species such as rice and Arabidopsis to gain access to the nutrients that support virulence. The genetic manipulation of SWEETs has led to the generation of bacterial blight (BB)-resistant rice varieties. Similarly, while the overexpression of the SWEETs involved in sucrose export from leaves and pathogenesis led to growth retardation and yield penalties, plants overexpressing SWEETs show improved disease resistance. Such findings demonstrate the complex functions of SWEETs in growth and stress tolerance. Here, we review the importance of SWEETs in plant-pathogen and source-sink interactions and abiotic stress resistance. We highlight the possible applications of SWEETs in crop improvement programmes aimed at improving sink and source strengths important for enhancing the sustainability of yield. We discuss how the adverse effects of the overexpression of SWEETs on plant growth may be overcome.

An update on VEXAS syndrome.

INTRODUCTION: VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a recently described, late-onset, acquired autoinflammatory disorder caused by mutations in the UBA1 gene. The various clinical manifestations of VEXAS broadly divided into inflammatory or haematological. VEXAS defines a new disease category - the hematoinflammatory disorders triggered by somatic mutations restricted to blood but causing systemic inflammation with multi-organ involvement and associated with aberrant bone marrow status. VEXAS causes significant morbidity and reduced life expectancy, but the optimum standard of care remains undefined. AREAS COVERED: This review describes the discovery of VEXAS, relevant genetic causes and immunopathology of the disease. A detailed account of its various clinical manifestations and disease mimics is provided. Current treatment and management options are discussed. EXPERT OPINION: New rare variants in UBA1 and VEXAS-like UBA1 negative cases are reported. Consensus diagnostic criteria might be required to define VEXAS and its related disorders. Investigation of sporadic, VEXAS-like cases will require the application of deep sequencing using DNA obtained from various cellular or tissue locations. Prospective studies are needed to define the optimal supportive and treatment options for patients with varying disease severity and prognosis. VEXAS-specific hematopoietic stem cell transplant selection criteria also require development.