Genetic tapestry of Capsicum fruit colors: a comparative analysis of four cultivated species.

KEY MESSAGE: Genome-wide association study of color spaces across the four cultivated Capsicum spp. revealed a shared set of genes influencing fruit color, suggesting mechanisms and pathways across Capsicum species are conserved during the speciation. Notably, Cytochrome P450 of the carotenoid pathway, MYB transcription factor, and pentatricopeptide repeat-containing protein are the major genes responsible for fruit color variation across the Capsicum species. Peppers (Capsicum spp.) rank among the most widely consumed spices globally. Fruit color, serving as a determinant for use in food colorants and cosmeceuticals and an indicator of nutritional contents, significantly influences market quality and price. Cultivated Capsicum species display extensive phenotypic diversity, especially in fruit coloration. Our study leveraged the genetic variance within four Capsicum species (Capsicum baccatum, Capsicum chinense, Capsicum frutescens, and Capsicum annuum) to elucidate the genetic mechanisms driving color variation in peppers and related Solanaceae species. We analyzed color metrics and chromatic attributes (Red, Green, Blue, L*, a*, b*, Luminosity, Hue, and Chroma) on samples cultivated over six years (2015-2021). We resolved genomic regions associated with fruit color diversity through the sets of SNPs obtained from Genotyping by Sequencing (GBS) and genome-wide association study (GWAS) with a Multi-Locus Mixed Linear Model (MLMM). Significant SNPs with FDR correction were identified, within the Cytochrome P450, MYB-related genes, Pentatricopeptide repeat proteins, and ABC transporter family were the most common among the four species, indicating comparative evolution of fruit colors. We further validated the role of a pentatricopeptide repeat-containing protein (Chr01:31,205,460) and a cytochrome P450 enzyme (Chr08:45,351,919) via competitive allele-specific PCR (KASP) genotyping. Our findings advance the understanding of the genetic underpinnings of Capsicum fruit coloration, with developed KASP assays holding potential for applications in crop breeding and aligning with consumer preferences. This study provides a cornerstone for future research into exploiting Capsicum's diverse fruit color variation.

From genes to ecosystems: Decoding plant tolerance mechanisms to arsenic stress.

Arsenic (As), a metalloid of considerable toxicity, has become increasingly bioavailable through anthropogenic activities, raising As contamination levels in groundwater and agricultural soils worldwide. This bioavailability has profound implications for plant biology and farming systems. As can detrimentally affect crop yield and pose risks of bioaccumulation and subsequent entry into the food chain. Upon exposure to As, plants initiate a multifaceted molecular response involving crucial signaling pathways, such as those mediated by calcium, mitogen-activated protein kinases, and various phytohormones (e.g., auxin, methyl jasmonate, cytokinin). These pathways, in turn, activate enzymes within the antioxidant system, which combat the reactive oxygen/nitrogen species (ROS and RNS) generated by As-induced stress. Plants exhibit a sophisticated genomic response to As, involving the upregulation of genes associated with uptake, chelation, and sequestration. Specific gene families, such as those coding for aquaglyceroporins and ABC transporters, are key in mediating As uptake and translocation within plant tissues. Moreover, we explore the gene regulatory networks that orchestrate the synthesis of phytochelatins and metallothioneins, which are crucial for As chelation and detoxification. Transcription factors, particularly those belonging to the MYB, NAC, and WRKY families, emerge as central regulators in activating As-responsive genes. On a post-translational level, we examine how ubiquitination pathways modulate the stability and function of proteins involved in As metabolism. By integrating omics findings, this review provides a comprehensive overview of the complex genomic landscape that defines plant responses to As. Knowledge gained from these genomic and epigenetic insights is pivotal for developing biotechnological strategies to enhance crop As tolerance.

Woolly mutation with the Get02 locus overcomes the polygenic nature of trichome-based pest resistance in tomato.

Type-IV glandular trichomes, which only occur in the juvenile developmental phase of the cultivated tomato (Solanum lycopersicum), produce acylsugars that broadly protect against arthropod herbivory. Previously, we introgressed the capacity to retain type-IV trichomes in the adult phase from the wild tomato, Solanum galapagense, into the cultivated species cv. Micro-Tom (MT). The resulting MT-Galapagos enhanced trichome (MT-Get) introgression line contained 5 loci associated with enhancing the density of type-IV trichomes in adult plants. We genetically dissected MT-Get and obtained a subline containing only the locus on Chromosome 2 (MT-Get02). This genotype displayed about half the density of type-IV trichomes compared to the wild progenitor. However, when we stacked the gain-of-function allele of WOOLLY, which encodes a homeodomain leucine zipper IV transcription factor, Get02/Wo exhibited double the number of type-IV trichomes compared to S. galapagense. This discovery corroborates previous reports positioning WOOLLY as a master regulator of trichome development. Acylsugar levels in Get02/Wo were comparable to the wild progenitor, although the composition of acylsugar types differed, especially regarding fewer types with medium-length acyl chains. Agronomical parameters of Get02/Wo, including yield, were comparable to MT. Pest resistance assays showed enhanced protection against silverleaf whitefly (Bemisia tabaci), tobacco hornworm (Manduca sexta), and the fungus Septoria lycopersici. However, resistance levels did not reach those of the wild progenitor, suggesting the specificity of acylsugar types in the pest resistance mechanism. Our findings in trichome-mediated resistance advance the development of robust, naturally resistant tomato varieties, harnessing the potential of natural genetic variation. Moreover, by manipulating only 2 loci, we achieved exceptional results for a highly complex, polygenic trait, such as herbivory resistance in tomato.

A Genome-Wide Identification and Comparative Analysis of the Heavy-Metal-Associated Gene Family in Cucurbitaceae Species and Their Role in Cucurbita pepo under Arsenic Stress.

The heavy-metal-associated (HMA) proteins are a class of PB1-type ATPases related to the intracellular transport and detoxification of metals. However, due to a lack of information regarding the HMA gene family in the Cucurbitaceae family, a comprehensive genome-wide analysis of the HMA family was performed in ten Cucurbitaceae species: Citrullus amarus, Citrullus colocynthis, Citrullus lanatus, Citrullus mucosospermus, Cucumis melo, Cucumis sativus, Cucurbita maxima, Cucurbita moschata, Cucurbita pepo, and Legenaria siceraria. We identified 103 Cucurbit HMA proteins with various members, ranging from 8 (Legenaria siceraria) to 14 (Cucurbita pepo) across species. The phylogenetic and structural analysis confirmed that the Cucurbitaceae HMA protein family could be further classified into two major clades: Zn/Co/Cd/Pb and Cu/Ag. The GO-annotation-based subcellular localization analysis predicted that all HMA gene family members were localized on membranes. Moreover, the analysis of conserved motifs and gene structure (intron/exon) revealed the functional divergence between clades. The interspecies microsynteny analysis demonstrated that maximum orthologous genes were found between species of the Citrullus genera. Finally, nine candidate HMA genes were selected, and their expression analysis was carried out via qRT-PCR in root, leaf, flower, and fruit tissues of C. pepo under arsenic stress. The expression pattern of the CpeHMA genes showed a distinct pattern of expression in root and shoot tissues, with a remarkable expression of CpeHMA6 and CpeHMA3 genes from the Cu/Ag clade. Overall, this study provides insights into the functional analysis of the HMA gene family in Cucurbitaceae species and lays down the basic knowledge to explore the role and mechanism of the HMA gene family to cope with arsenic stress conditions.

Drosophila melanogaster as a Translational Model System to Explore the Impact of Phytochemicals on Human Health.

Fruits, vegetables, and spices are natural sources of bioactive phytochemicals, such as polyphenols, carotenoids, flavonoids, curcuminoids, terpenoids, and capsaicinoids, possessing multiple health benefits and relatively low toxicity. These compounds found in the diet play a central role in organism development and fitness. Given the complexity of the whole-body response to dietary changes, invertebrate model organisms can be valuable tools to examine the interplay between genes, signaling pathways, and metabolism. Drosophila melanogaster, an invertebrate model with its extensively studied genome, has more than 70% gene homology to humans and has been used as a model system in biological studies for a long time. The notable advantages of Drosophila as a model system, such as their low maintenance cost, high reproductive rate, short generation time and lifespan, and the high similarity of metabolic pathways between Drosophila and mammals, have encouraged the use of Drosophila in the context of screening and evaluating the impact of phytochemicals present in the diet. Here, we review the benefits of Drosophila as a model system for use in the study of phytochemical ingestion and describe the previously reported effects of phytochemical consumption in Drosophila.

QTL and PACE analyses identify candidate genes for anthracnose resistance in tomato.

Anthracnose, caused by the fungal pathogen Colletotrichum spp., is one of the most significant tomato diseases in the United States and worldwide. No commercial cultivars with anthracnose resistance are available, limiting resistant breeding. Cultivars with genetic resistance would significantly reduce crop losses, reduce the use of fungicides, and lessen the risks associated with chemical application. A recombinant inbred line (RIL) mapping population (N=243) has been made from a cross between the susceptible US28 cultivar and the resistant but semiwild and small-fruited 95L368 to identify quantitative trait loci (QTLs) associated with anthracnose resistance. The RIL population was phenotyped for resistance by inoculating ripe field-harvested tomato fruits with Colletotrichum coccodes for two seasons. In this study, we identified twenty QTLs underlying resistance, with a range of phenotypic variance of 4.5 to 17.2% using a skeletal linkage map and a GWAS. In addition, a QTLseq analysis was performed using deep sequencing of extreme bulks that validated QTL positions identified using traditional mapping and resolved candidate genes underlying various QTLs. We further validated AP2-like ethylene-responsive transcription factor, N-alpha-acetyltransferase (NatA), cytochrome P450, amidase family protein, tetratricopeptide repeat, bHLH transcription factor, and disease resistance protein RGA2-like using PCR allelic competitive extension (PACE) genotyping. PACE assays developed in this study will enable high-throughput screening for use in anthracnose resistance breeding in tomato.

Trombosis de seno venoso en paciente en puerperio mediato. Reporte de caso / Venous sinus thrombosis in a patient during the immediate puerperium. Case report

Resumen ANTECEDENTES: La trombosis del seno venoso representa el 1% de los eventos vasculares cerebrales; su incidencia es de 5 casos por cada millón de habitantes y su mortalidad es del 10%. Los senos sagital superior y venoso transversal son los más afectados. El embarazo es un factor de riesgo especial pues la trombosis se registra en el 0.01% de las gestaciones. CASO CLÍNICO: Paciente de 40 años, primigesta, con embarazo gemelar bicorial biamniótico de 33.6 semanas. Se ingresó al servicio de Urgencias debido al diagnóstico de preeclampsia con criterios de severidad, con presión arterial de 160-100 mmHg y transaminasemia. Se le indicó tratamiento antihipertensivo y sulfato de magnesio intravenoso. Se decidió la finalización del embarazo por cesárea. Al cuarto día poscesárea tuvo disminución de la fuerza en ambos brazos, pérdida del tono muscular en los miembros pélvicos, cefalea holocraneana y alteración del estado de alerta (Glasgow de 14). Mediante resonancia magnética se evidenció la oclusión del seno longitudinal superior e isquemia en la región parieto occipital izquierda. Se le administraron anticoagulantes y analgésicos con los que evolucionó adecuadamente; se dio de alta sin complicaciones. CONCLUSIONES: La trombosis del seno venoso implica un reto cuando no se tiene una alta sospecha diagnóstica en pacientes con signos y síntomas neurológicos y, más aún, cuando se agregan factores de riesgo protrombóticos, como el embarazo y el puerperio. El diagnóstico oportuno brinda la oportunidad de iniciar el tratamiento adecuado y disminuir los síntomas y comorbilidades.

Abstract BACKGROUND: Venous sinus thrombosis accounts for 1% of cerebral vascular events; its incidence is 5 cases per million population and its mortality is 10%. The superior sagittal and transverse venous sinuses are the most affected. Pregnancy is a special risk factor since thrombosis is registered in 0.01% of pregnancies. CLINICAL CASE: A 40-year-old primigravida patient with a 33.6 week biamniotic twin pregnancy. She was admitted to the Emergency Department due to the diagnosis of preeclampsia with severity criteria, with blood pressure of 160-100 mmHg and transaminasemia. She was prescribed antihypertensive treatment and intravenous magnesium sulfate. It was decided to terminate the pregnancy by cesarean section. On the fourth post-cesarean day she had decreased strength in both arms, loss of muscle tone in the pelvic limbs, holocranial headache and altered alertness (Glasgow of 14). Magnetic resonance imaging showed occlusion of the superior longitudinal sinus and ischemia in the left parietooccipital region. He was administered anticoagulants and analgesics with which he evolved adequately; he was discharged without complications. CONCLUSIONS: Venous sinus thrombosis implies a challenge when there is no high diagnostic suspicion in patients with neurological signs and symptoms and, even more so, when prothrombotic risk factors are added, such as pregnancy and puerperium. Timely diagnosis provides the opportunity to initiate appropriate treatment and reduce symptoms and comorbidities.

Cecal Diverticulitis in a Geriatric Patient.

The authors present the case of a 70-year-old man with cecal (right-sided) diverticulitis. Cecal diverticulitis is frequently confused with appendicitis, which could potentially lead to unnecessary intervention. Cecal diverticulitis is usually seen in the fourth decade of life, whereas the patient who presented was significantly older. The risk factors, clinical presentation, imaging findings, and emergency department management are discussed.

Peppers in Diet: Genome-Wide Transcriptome and Metabolome Changes in Drosophila melanogaster.

The habanero pepper (Capsicum chinense) is an increasingly important spice and vegetable crop worldwide because of its high capsaicin content and pungent flavor. Diets supplemented with the phytochemicals found in habanero peppers might cause shifts in an organism's metabolism and gene expression. Thus, understanding how these interactions occur can reveal the potential health effects associated with such changes. We performed transcriptomic and metabolomic analyses of Drosophila melanogaster adult flies reared on a habanero pepper diet. We found 539 genes/59 metabolites that were differentially expressed/accumulated in flies fed a pepper versus control diet. Transcriptome results indicated that olfactory sensitivity and behavioral responses to the pepper diet were mediated by olfactory and nutrient-related genes including gustatory receptors (Gr63a, Gr66a, and Gr89a), odorant receptors (Or23a, Or59a, Or82a, and Orco), and odorant-binding proteins (Obp28a, Obp83a, Obp83b, Obp93a, and Obp99a). Metabolome analysis revealed that campesterol, sitosterol, and sucrose were highly upregulated and azelaic acid, ethyl phosphoric acid, and citric acid were the major metabolites downregulated in response to the habanero pepper diet. Further investigation by integration analysis between transcriptome and metabolome data at gene pathway levels revealed six unique enriched pathways, including phenylalanine metabolism; insect hormone biosynthesis; pyrimidine metabolism; glyoxylate, and dicarboxylate metabolism; glycine, serine, threonine metabolism; and glycerolipid metabolism. In view of the transcriptome and metabolome findings, our comprehensive analysis of the response to a pepper diet in Drosophila have implications for exploring the molecular mechanism of pepper consumption.

Impact of Alzheimer's Disease on Caregivers in the United States.

Background/Objective: First discovered by Alois Alzheimer in 1906, Alzheimer's disease (AD) has become a growing global health concern with numerous implications for individuals and modern society. As patients' symptoms of dementia continue to worsen, they gradually grow more limited in their independence. As a result, family members and close acquaintances often become caregivers for the patient and become more involved in maintaining the patient's lifestyle. The authors of this research sought to study what motivates caregivers to look after AD patients and the impact of AD on their lifestyles and physical, mental, and social health. Methods: The authors crafted a survey of fourteen questions and collected data from 200 caregivers regarding AD's impact on their physical, emotional, and social health along with their key demographic and background information (e.g. whether or not they are a caregiver for a patient with AD). Results: The results indicate that most AD caregivers are family members (78%). AD often strains the caregiver's relationship with the patient (47.5%), and 58% of participating caregivers report extreme stress levels while 65% realize it is incredibly difficult to take care of a patient. Because of the increased levels of stress, 47% of participating caregivers sleep less; 43% feel more isolated from their family; and, 35.5% did not try to get help from others. Love and a strong sense of duty seem to be the primary motivation for caregivers to take care of a patient. Worry for the patient (50%), financial worries (12.5%), lack of medical experience (10.5%), and their own health (10.5%) seem to be the primary stressors for caregivers. Caregivers rely on numerous support systems and coping mechanisms, with physical activity (54.5%) and increased alcohol and marijuana usage (35.5%) the most frequent. Conclusions: Although caregivers have support systems and found coping methods that would alleviate their burden of caring for a patient with AD, the clear negative impact AD has on caregivers affects their physical, mental, and social health. As there is currently no cure for AD, compassion and greater support for caregivers are necessary.

COVID-19 Vaccine Hesitancy Among Healthcare Providers.

Objective: Vaccine hesitancy among healthcare providers can compromise public confidence in vaccination during the ongoing COVID-19 global epidemic and increase susceptibility to life-threatening disease. We sought to investigate predictors of openness to vaccination among healthcare workers who choose not to be vaccinated against COVID-19 in order to explore potential solutions. Methods: Physicians, physician assistants, and nurses who chose not to be vaccinated were surveyed to decipher reasons for vaccine refusal and personal loss due to the virus along with demographic variables. Multivariate logistic regression analysis evaluated whether provider role, parenthood, and death of family or friends were associated with strong versus relative vaccine refusal. Results: The predominant reasons for vaccine hesitancy in this cohort of health care workers who had access to, but chose not to be vaccinated (n=500) were a concern for vaccine side effects (69.6%) and the belief that the vaccines are inadequately studied (61.6%). Being a physician, a parent, and having no experience of death in the family or friends had 2.64 times (95% CI: 1.65-4.23, p < 0.001), 1.72 times (95% CI: 1.05-2.81, p = 0.032), and 1.70 times (95% CI: 1.06-2.72, p = 0.028) the odds of strong vaccine refusal, respectively. Older age (35 and up) respondents were 1.83 times (95% CI: 1.24-2.68, p = 0.002) more likely to be open to vaccination.

Acute Submandibular Sialadenitis.

Sialadenitis is a stone in the salivary system that often presents as acute pain and swelling and can cause significant distress to patients. Here, we present a case of submandibular sialadenitis in a 41-year-old woman who experienced sudden-onset facial and neck pain and swelling. In addition, we discuss the diagnosis and emergency department management.

Non-ST Segment Elevation Myocardial Infarction Associated With Cocaine Use.

We present the case of a 23-year-old male with no significant past medical history who experienced acute chest pain. A diagnostic workup revealed that the patient had a non-ST-segment elevation myocardial infarction. Although the patient was not forthcoming initially with his cocaine use, he did admit it later in his emergency department course. The timing of his rise and fall of troponin is presented. The pathophysiology of cocaine-related chest pain and infarction is discussed. The patient continued to make an uneventful recovery.

Lateral Malleolar Fracture.

The authors present the case of a young woman who sustained a lateral malleolar fracture. The Emergency Departement presentation, diagnosis and initial acute treatment is discussed.

Bilateral Tonsillitis With Peritonsillar Abscess.

The authors present a case of an adolescent female who presented to the emergency department with a second case of tonsillitis in the span of two weeks. The patient recovered after treatment with a broader-spectrum antibiotic and was discharged home. The authors highlight the importance of weighing the costs and benefits of tonsillectomy with the potential that additional antibiotics may be enough in cases of recurrent tonsillitis.

Anaphylaxis Presenting as Uvulitis.

The authors present a case of a young man who woke up with uvular swelling resulting in a severely narrowed airway. He had ingested peanut butter the prior night but was unaware of any allergies. He was treated with epinephrine, diphenhydramine, and methylprednisolone which resulted in resolution of the airway compromise. The authors discuss the mechanism of anaphylaxis and the emergency management of this life-threatening condition.

Exploration into natural variation for genes associated with fruit shape and size among Capsicum chinense collections.

Phenotype diversity within cultivated Capsicum chinense is particularly evident for fruit shape and size. We used this diversity in C. chinense to further unravel the genetic mechanisms underlying fruit shape variation in pepper and related Solanaceous species. We identified candidate genes for C. chinense fruit shape, explored their contribution to population structure, and characterized their potential function in pepper fruit shape. Using genotyping by sequencing, we identified 43,081 single nucleotide polymorphisms (SNPs) from diverse collections of C. chinense. Principal component, neighbor-joining tree, and population structure analyses resolved 3 phylogenetically robust clusters associated with fruit shapes. Genome-wide association study (GWAS) was used to identify associated genomic regions with various fruit shape traits obtained from image analysis with Tomato Analyzer software. In our GWAS, we selected 12 SNPs associated with locule number trait and 8 SNP markers associated with other fruit shape traits such as perimeter, area, obovoid, ellipsoid and morphometrics (5y, 6y and 7y). The SNPs in CLAVATA1, WD-40, Auxin receptor, AAA type ATPase family protein, and RNA polymerase III genes were the major markers identified for fruit locule number from our GWAS results. Furthermore, we found SNPs in tetratricopeptide-repeat thioredoxin-like 3, enhancer of ABA co-receptor 1, subunit of exocyst complex 8 and pleiotropic drug resistance proteins associated with various fruit shape traits. CLAVATA1, WD-40 and Auxin receptor genes are known genes that affect tomato fruit shape. In this study, we used Arabidopsis thaliana T-DNA insertion knockout mutants and expression profiles for functional characterization of newly identified genes and to understand their role in fruit shape.

Identification of miRNAs and Their Targets Involved in Flower and Fruit Development across Domesticated and Wild Capsicum Species.

MicroRNAs (miRNAs) are regulators of the post-transcription stage of gene activity documented to play central roles in flower and fruit development in model plant species. However, little is known about their roles and differences in domesticated and wild Capsicum species. In this study, we used high-throughput sequencing to analyze the miRNA content at three developmental stages (flower, small fruit, and middle fruit) from two cultivated (C. baccatum and C. annuum) and two wild (C. chacoense and C. eximium) pepper species. This analysis revealed 22 known and 27 novel miRNAs differentially expressed across species and tissues. A number of stage- and species-specific miRNAs were identified, and Gene Ontology terms were assigned to 138 genes targeted by the miRNAs. Most Gene Ontology terms were for the categories "genetic information processing", "signaling and cellular processes", "amino acid metabolism", and "carbohydrate metabolism". Enriched KEGG analysis revealed the pathways amino acids, sugar and nucleotide metabolism, starch and sucrose metabolism, and fructose-mannose metabolism among the principal ones regulated by miRNAs during pepper fruit ripening. We predicted miRNA-target gene interactions regulating flowering time and fruit development, including miR156/157 with SPL genes, miR159 with GaMYB proteins, miR160 with ARF genes, miR172 with AP2-like transcription factors, and miR408 with CLAVATA1 gene across the different Capsicum species. In addition, novel miRNAs play an important role in regulating interactions potentially controlling plant pathogen defense and fruit quality via fructokinase, alpha-L-arabinofuranosidase, and aromatic and neutral amino acid transporter. Overall, the small RNA-sequencing results from this study represent valuable information that provides a solid foundation for uncovering the miRNA-mediated mechanisms of flower and fruit development between domesticated and wild Capsicum species.

Altered chromatin conformation and transcriptional regulation in watermelon following genome doubling.

Polyploidy has played a crucial role in plant evolution, development and function. Synthetic autopolyploid represents an ideal system to investigate the effects of polyploidization on transcriptional regulation. In this study, we deciphered the impact of genome duplication at phenotypic and molecular levels in watermelon. Overall, 88% of the genes in tetraploid watermelon followed a >1:1 dosage effect, and accordingly, differentially expressed genes were largely upregulated. In addition, a great number of hypomethylated regions (1688) were identified in an isogenic tetraploid watermelon. These differentially methylated regions were localized in promoters and intergenic regions and near transcriptional start sites of the identified upregulated genes, which enhances the importance of methylation in gene regulation. These changes were reflected in sophisticated higher-order chromatin structures. The genome doubling caused switching of 108 A and 626 B compartments that harbored genes associated with growth, development and stress responses.