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Nutrition and Health in Arab Adolescents (NaHAR): Study protocol for the determination of ethnic-specific body fat and anthropometric cut-offs to identify metabolic syndrome. PLoS One 2024; 19:e0298306. [PMID: 38394061 PMCID: PMC10889849 DOI: 10.1371/journal.pone.0298306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 01/23/2024] [Indexed: 02/25/2024] Open
Abstract
The prevalence of adolescent obesity in the Middle-East is considered among the highest in the world. Obesity in adolescents is associated with several cardiometabolic abnormalities, the constellation of which is referred to as the metabolic syndrome (MetS). This multi-country cross-sectional study aims to determine the optimal cut-off values for body fat (BF); body mass index (BMI) z-score; waist circumference (WC) percentile, and mid-upper arm circumference (MUAC) for the prediction of MetS among adolescents from Kingdom of Saudi-Arabia (KSA), Kuwait, Jordan, Lebanon and Syria. A secondary objective is to examine the validity of Bioelectrical Impendence Vector Analysis (BIVA) in estimating BF against the deuterium dilution technique (DDL). In each country, a sample of 210 adolescents will be recruited. Data collection will include demographics, socioeconomic, lifestyle and dietary data using a multi-component questionnaire; anthropometric measurements will be obtained and body composition will be assessed using the DDL and BIVA; blood pressure and biochemical assessment will be performed for the identification of the MetS. Receiver operating characteristic analyses will be undertaken to determine optimal cut-off values of BMI, WC, MUAC and BF in identifying those with MetS. Odds ratios (OR) and their respective 95% confidence interval (CI) for the association of the anthropometric measurements with MetS will be computed based on multiple logistic regression analysis models. The Bland and Altman approach will be adopted to compare BIVA against the reference DDL method for the determination of body composition parameters. This study responds to the need for ethnic-specific anthropometric cut-offs for the identification of excess adiposity and associated cardiometabolic risks in the adolescent population. The adoption of the generated cut-offs may assist policy makers, public health professionals and clinical practitioners in providing ethnic-specific preventive and curative strategies tailored to adolescents in the region.
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Discordance in exclusive breastfeeding between maternal recall and deuterium dose-to-mother technique during the first 6 months of infants: A multi-country study in Asia. Eur J Clin Nutr 2024; 78:135-140. [PMID: 37838807 DOI: 10.1038/s41430-023-01353-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 08/18/2023] [Accepted: 10/02/2023] [Indexed: 10/16/2023]
Abstract
PURPOSE This study aimed to assess the agreement in EBF between maternal recall and the dose-to-mother (DTM) technique. METHODS Indonesia, Malaysia, Mongolia, Pakistan, Sri Lanka, Thailand, and Vietnam participated in the study. A total of 207 and 118 mother-infant pairs were assessed at 3 and 6 months of child's age. Using a standardized questionnaire, mothers were asked to recall child feeding during the previous 24 h, at 3 and 6 months. Those recalled to be EBF proceeded to be assessed using DTM technique. Non-milk oral intake (NMOI) cutoff of 86.6 g/d was used to classify EBF. RESULTS According to DTM, 66% of infants were EBF at 3 months, while only 22% were EBF at 6 months. At 3 months, the overall % agreement between maternal recall and DTM method was 68%, kappa 0.06 (95% CI: 0.07-0.20), and at 6 months, the % agreement was only 21%, kappa -0.031 (95% CI -0.168 to 0.107). Human milk intakes were similar at 3 months and 6 months when expressed as g/d, but decreased when expressed as g/kg/d, with a large variation within and between countries; Pakistan being the lowest. CONCLUSION This study showed there were declining levels of EBF from 3 to 6 months in the participating countries from Asia and the agreement between maternal recall and DTM technique to classify EBF was low. To ensure that the DTM technique can be more widely used in evaluating breastfeeding promotion programs, consensus on the appropriate NMOI cutoff and simplification of the DTM protocol is necessary.
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Body composition assessment in 6-month-old infants: A comparison of two- and three-compartment models using data from the Baby-bod study. Eur J Clin Nutr 2024:10.1038/s41430-023-01394-5. [PMID: 38233534 DOI: 10.1038/s41430-023-01394-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 12/07/2023] [Accepted: 12/12/2023] [Indexed: 01/19/2024]
Abstract
BACKGROUND/OBJECTIVES An appreciation of infant body composition is helpful to understand the 'quality' of growth in early life. Air displacement plethysmography (ADP) using PEA POD and the deuterium dilution (DD) technique are commonly used body composition approaches in infants. We evaluated the comparability of body composition assessed using both techniques with two-compartment (2C) and three-compartment (3C) models in 6-month-old infants. SUBJECTS/METHODS Infant fat mass (FM) and percent fat mass (%FM) obtained from a 2C model using PEA POD (2C-PP) and a 2C model using the deuterium dilution technique (2C-DD) were compared to those derived from a 3C model, and to each other, using Bland-Altman analysis and Deming regression. RESULTS Measurements were available from 68 infants (93% Caucasian, 53% male). The mean biases were not significant between any of the method comparisons. However, significant constant and proportional biases were identified in 2C-DD vs 3C and 2C-PP vs 2C-DD, but not in the 2C-PP vs 3C comparison. Furthermore, we observed significant associations between the mean differences and infants' percent total body water (%TBW). CONCLUSIONS While no significant between-method mean differences were found in body composition estimates, some comparisons revealed significant constant and proportional biases and notable associations between the mean differences and %TBW were observed. Our results emphasise the importance of method choice, ensuring methodological uniformity in long-term studies, and carefully considering and regulating multiple pre-analytical variables, such as the hydration status of the participants.
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Effect of a Probiotic Beverage Enriched with Cricket Proteins on the Gut Microbiota: Composition of Gut and Correlation with Nutritional Parameters. Foods 2024; 13:204. [PMID: 38254505 PMCID: PMC10814958 DOI: 10.3390/foods13020204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/19/2023] [Accepted: 12/25/2023] [Indexed: 01/24/2024] Open
Abstract
The health and balance of the gut microbiota are known to be linked to diet composition and source, with fermented products and dietary proteins potentially providing an exceptional advantage for the gut. The purpose of this study was to evaluate the effect of protein hydrolysis, using a probiotic beverage enriched with either cricket protein (CP) or cricket protein hydrolysates (CP.Hs), on the composition of the gut microbiota of rats. Taxonomic characterization of the gut microbiota in fecal samples was carried out after a 14-day nutritional study to identify modifications induced by a CP- and CP.H-enriched fermented probiotic product. The results showed no significant differences (p > 0.05) in the diversity and richness of the gut microbiota among the groups fed with casein (positive control), CP-enriched, and fermented CP.H-enriched probiotic beverages; however, the overall composition of the microbiota was altered, with significant modifications in the relative abundance of several bacterial families and genera. In addition, fermented CP.H-enriched probiotic beverages could be related to the decrease in the number of potential pathogens such as Enterococcaceae. The association of gut microbiota with the nutritional parameters was determined and the results showed that digestibility and the protein efficiency ratio (PER) were highly associated with the abundance of several taxa.
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Infant growth and body composition from birth to 24 months: are infants developing the same? Eur J Clin Nutr 2024:10.1038/s41430-023-01386-5. [PMID: 38172346 DOI: 10.1038/s41430-023-01386-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 11/18/2023] [Accepted: 12/01/2023] [Indexed: 01/05/2024]
Abstract
BACKGROUND Given the importance of infancy for establishing growth trajectories, with later-life health consequences, we investigated longitudinal body composition among infants from six economically and ethnically diverse countries. METHODS We recruited mother-infant dyads using the WHO Multicenter Growth Reference Study criteria. We measured fat-free mass (FFM) in 1393 (49% female) infants from birth to 6 months of age (Australia, India, and South Africa; n = 468), 3-24 months of age (Brazil, Pakistan, South Africa, and Sri Lanka; n = 925), and derived fat mass (FM), fat mass index (FMI), and fat-free mass index (FFMI). Height-for-age (HAZ), weight-for-age (WAZ), and weight-for-length (WHZ) Z-scores were computed. Sex differences were assessed using a t-test, and country differences using a one-way analysis of covariance. We further compared subsamples of children with average (-0.25 > HAZ < +0.25), below-average (≤-0.25) and above-average (≥+0.25) HAZ. RESULTS HAZ performed well between 0 and 6 months, but less so between 3 and 24 months. The stunting prevalence peaked at 10.3% for boys and 7.8% for girls, at 24 months. By 24 months, girls had greater FMI (10%) than boys. There were significant differences in FFM (both sexes in all countries) and FM (Brazilian boys, Pakistani and South African girls) by 24 months of age between infants with average, above-average, and below-average HAZ. CONCLUSION In a multi-country sample representing more ideal maternal conditions, body composition was heterogeneous even among infants who exhibited ideal length. Having a mean HAZ close to the median of the WHO standard for length reduced FFM between-country heterogeneity but not FM, suggesting that other factors may influence adiposity.
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Preparation, Radiolabeling with 68Ga/ 177Lu and Preclinical Evaluation of Novel Angiotensin Peptide Analog: A New Class of Peptides for Breast Cancer Targeting. Pharmaceuticals (Basel) 2023; 16:1550. [PMID: 38004416 PMCID: PMC10675340 DOI: 10.3390/ph16111550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 09/17/2023] [Accepted: 09/22/2023] [Indexed: 11/26/2023] Open
Abstract
AIM Angiotensin II (AngII) is known to play a significant part in the development of breast cancer by triggering cell propagation of breast cancer, tumor angiogenesis, and regulating tumor invasion and cell migration. AngII arbitrates its action via two G-protein-coupled receptors, AngII type 1 receptor (AT1) and AngII type 2 receptor (AT2). Overexpression of the AT1 receptor in breast cancer cells seems to promote tumor growth and angiogenesis, thus targeting the AT1 receptor using AngII peptide would facilitate the detection of breast carcinoma. We developed an AngII peptide intending to assess whether the peptide of the renin-angiotensin system holds the ability to target AT1 receptor-overexpressing breast cancer in vivo. METHODS DOTA-coupled AngII peptide was synthesized by conventional solid-phase peptide synthesis according to Fmoc/HATU chemistry. 68Ga/177Lu labeled AngII peptide was evaluated for its binding with TNBC MDA-MB-231 and ER+ MCF7 cell lines. Pharmacokinetics was studied in healthy balb/c mice and in vivo tumor targeting in nude mice with MDA-MB-231 tumors xenografts. RESULTS DOTA-AngII peptide was labeled efficiently with 68Ga/177Lu with high labeling efficiency (≥90%). The stability of the radiopeptide in human plasma was found to be high. The AngII peptide analog showed nanomolar (<40 nM) AT1 receptor-specific binding affinity. The radioactivity internalized into MDA-MBA-231 and MCF7 cells were 14.97% and 11.75%, respectively. In vivo, biodistribution in balb/c mice exhibited efficient clearance of 68Ga/177Lu-DOTA-AngII peptide from the blood and elimination predominantly by the renal system due to its hydrophilic nature. A low amount of radioactivity was seen in the major organs including lungs, liver, stomach, spleen, and intestines (<3% ID/g) except the kidneys. A high renal-urinary excretion was observed for the radiotracer. In the TNBC MDA-MB-231 xenografts model, radiolabeled AngII peptide exhibited specific and effective AT1-based targeting in vivo. A rapid and efficient tumor targeting (2.18% ID/g at 45 min p.i.) together with fast renal excretion (~67% ID) highlights the tumor-targeting potential of the radiotracer. The AT1 receptor specificity of the radiotracer was validated by blocking assays. Furthermore, PET imaging provided sufficient visualization of MDA-MB-231 tumors in nude mice. CONCLUSION Our findings suggest that 68Ga/177Lu-DOTA-AngII peptide can be useful for the theranostic application of breast carcinomas. This study suggests the potential of this innovative class of peptides for rapid and efficient targeting of tumors and warrants further evaluation.
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Sequencing 4.3 million mutations in wheat promoters to understand and modify gene expression. Proc Natl Acad Sci U S A 2023; 120:e2306494120. [PMID: 37703281 PMCID: PMC10515147 DOI: 10.1073/pnas.2306494120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 08/03/2023] [Indexed: 09/15/2023] Open
Abstract
Wheat is an important contributor to global food security, and further improvements are required to feed a growing human population. Functional genetics and genomics tools can help us to understand the function of different genes and to engineer beneficial changes. In this study, we used a promoter capture assay to sequence 2-kb regions upstream of all high-confidence annotated genes from 1,513 mutagenized plants from the tetraploid wheat variety Kronos. We identified 4.3 million induced mutations with an accuracy of 99.8%, resulting in a mutation density of 41.9 mutations per kb. We also remapped Kronos exome capture reads to Chinese Spring RefSeq v1.1, identified 4.7 million mutations, and predicted their effects on annotated genes. Using these predictions, we identified 59% more nonsynonymous substitutions and 49% more truncation mutations than in the original study. To show the biological value of the promoter dataset, we selected two mutations within the promoter of the VRN-A1 vernalization gene. Both mutations, located within transcription factor binding sites, significantly altered VRN-A1 expression, and one reduced the number of spikelets per spike. These publicly available sequenced mutant datasets provide rapid and inexpensive access to induced variation in the promoters and coding regions of most wheat genes. These mutations can be used to understand and modulate gene expression and phenotypes for both basic and commercial applications, where limited governmental regulations can facilitate deployment. These mutant collections, together with gene editing, provide valuable tools to accelerate functional genetic studies in this economically important crop.
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Infant body composition at 6 and 24 months: what are the driving factors? Eur J Clin Nutr 2023:10.1038/s41430-023-01321-8. [PMID: 37563230 DOI: 10.1038/s41430-023-01321-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 07/17/2023] [Accepted: 07/24/2023] [Indexed: 08/12/2023]
Abstract
BACKGROUND/OBJECTIVE Available evidence on infant body composition is limited. This study aimed to investigate factors associated with body composition at 6 and 24 months. SUBJECTS/METHODS Multicenter study with data from a 0 to 6-mo cohort (Australia, India and South Africa) and a 3 to 24-mo cohort (Brazil, Pakistan, South Africa, and Sri Lanka). For the 0-6-mo cohort, body composition was assessed by air-displacement plethysmography (ADP) and for the 3-24-month cohort by the deuterium dilution (DD) technique. Fat mass (FM), fat-free mass (FFM), FM index (FMI), and FFM index (FFMI) were calculated. Independent variables comprised the Gini index of the country, maternal and infant characteristics, and breastfeeding pattern at 3 months. For the 3-24-mo cohort, breastfeeding, and minimum dietary diversity (MDD) at 12 months were also included. Crude and adjusted analyses stratified by sex were conducted by multilevel modelling using mixed models. RESULTS At 6 months, every 1 kg increase in birth weight was associated with an increase of 0.716 kg in FFM and 0.582 kg/m2 in FFMI in girls, whereas in boys, the increase was of 0.277 kg in FFM. At 24 months, compared to those weaned before 12 months, girls still breastfed at 12 months presented a decrease of 0.225 kg in FM, 0.645 kg in FFM and 0.459 kg/m2 in FFMI, and in boys the decreases were of 0.467 kg in FM, 0.603 kg in FFM and 0.628 kg/m2 in FFMI. CONCLUSION Birth weight and breastfeeding are independent predictors of body composition in early life, irrespective of sex.
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Body composition from birth to 2 years. Eur J Clin Nutr 2023:10.1038/s41430-023-01322-7. [PMID: 37563231 DOI: 10.1038/s41430-023-01322-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/08/2023] [Accepted: 07/25/2023] [Indexed: 08/12/2023]
Abstract
Providing all infants with the best start to life is a universal but challenging goal for the global community. Historically, the size and shape of infants, quantified by anthropometry and commencing with birthweight, has been the common yardstick for physical growth and development. Anthropometry has long been considered a proxy for nutritional status during infancy when, under ideal circumstances, changes in size and shape are most rapid. Developed from data collected in the Multicentre Growth Reference Study (MGRS), WHO Child Growth Standards for healthy infants and children have been widely accepted and progressively adopted. In contrast, and somewhat surprisingly, much less is understood about the 'quality' of growth as reflected by body composition during infancy. Recent advances in body composition assessment, including the more widespread use of air displacement plethysmography (ADP) across the first months of life, have contributed to a progressive increase in our knowledge and understanding of growth and development. Along with stable isotope approaches, most commonly the deuterium dilution (DD) technique, the criterion measure of total body water (TBW), our ability to quantify lean and fat tissue using a two-compartment model, has been greatly enhanced. However, until now, global reference charts for the body composition of healthy infants have been lacking. This paper details some of the historical challenges associated with the assessment of body composition across the first two years of life, and references the logical next steps in growth assessments, including reference charts.
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Using Gamma Irradiation to Predict Sperm Competition Mechanism in Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae): Insights for a Future Management Strategy. INSECTS 2023; 14:681. [PMID: 37623391 PMCID: PMC10455075 DOI: 10.3390/insects14080681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 07/21/2023] [Accepted: 07/26/2023] [Indexed: 08/26/2023]
Abstract
The stink bug, Bagrada hilaris, is a pest of mainly Brassicaceae crops. It is native to Africa and Asia and was recently reported as invasive in the southwestern part of the USA and in South America. There are no mitigation programs in place that do not involve pesticides. Therefore, much attention has recently been paid to the study of this species in order to identify sustainable and effective control strategies, such as the Sterile Insect Technique (SIT). In order to evaluate the suitability of the SIT on this pest, the mechanism of post-copulatory sperm competition was investigated. This is a polyandrous species, and it is thus important to understand whether irradiated males are able to compete with wild, e.g., non-irradiated, males for sperm competition after matings. Sperm competition was studied by sequentially mating a healthy virgin female first with a non-irradiated male, and then with a γ-irradiated (Co-60) one, and again in the opposite order. Males were irradiated at three different doses: 60, 80, and 100 Gy. The fecundity and fertility of the females, in the two orders of mating, were scored in order to perform an initial assessment of the success of sperm competition with a P2 index. Sperm from the non-irradiated male were utilized at the lowest irradiation doses (60 and 80 Gy), whereas the irradiated sperm were preferentially utilized at the highest dose (100 Gy). Bagrada hilaris exhibited high variability in P2 indexes, indicating a sperm-mixing mechanism.
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Green Assessment of Phenolic Acid Composition and Antioxidant Capacity of Advanced Potato Mutant Lines through UPLC-qTOF-MS/MS Quantification. Foods 2023; 12:2616. [PMID: 37444356 DOI: 10.3390/foods12132616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 06/28/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
Potatoes are one of the most consumed crops worldwide. They contain a high amount of bioactive compounds such as phenolic compounds and vitamins with important antioxidant activities, which makes this crop of high biological value for human health. The goal of this research was to biochemically evaluate polyphenol levels and antioxidant capacities in parent and control genotypes compared to advanced mutant potato lines in the M1V8 generation. This will reveal the genetic changes that result from induced mutagenesis. The quantified compounds and the evaluated antioxidant activity boost the health benefits of consuming the improved mutant potatoes. In the present study, the phenolic composition and antioxidant activity of eighteen mutant and initial potato genotypes were analyzed by UPLC-qTOF-MS/MS and the ORAC method, respectively. In each of the hybrid combinations, mutant lines with an improved phenolic compound profile were observed. Representative samples from the third hybrid combination had notable increases in phenolic compound concentrations, as well as the presence of metabolites not found in the parental lines. With one exception, the remaining nine mutants showed significantly higher antioxidant capacities. The results will be used in future potato breeding programs, with participation of the valuable mutant lines containing new phenolic substances not present in the initial genotypes.
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Abstract
Fascioliasis is a plant- and waterborne zoonotic parasitic disease caused by two trematode species: (i) Fasciola hepatica in Europe, Asia, Africa, the Americas, and Oceania and (ii) F. gigantica, which is restricted to Africa and Asia. Fasciolid liver flukes infect mainly herbivores as ruminants, equids, and camelids but also omnivore mammals as humans and swine and are transmitted by freshwater Lymnaeidae snail vectors. Two phases may be distinguished in fasciolid evolution. The long predomestication period includes the F. gigantica origin in east-southern Africa around the mid-Miocene, the F. hepatica origin in the Near-Middle East of Asia around the latest Miocene to Early Pliocene, and their subsequent local spread. The short postdomestication period includes the worldwide spread by human-guided movements of animals in the last 12,000 years and the more recent transoceanic anthropogenic introductions of F. hepatica into the Americas and Oceania and of F. gigantica into several large islands of the Pacific with ships transporting livestock in the last 500 years. The routes and chronology of the spreading waves followed by both fasciolids into the five continents are redefined on the basis of recently generated knowledge of human-guided movements of domesticated hosts. No local, zonal, or regional situation showing disagreement with historical records was found, although in a few world zones the available knowledge is still insufficient. The anthropogenically accelerated evolution of fasciolids allows us to call them "peridomestic endoparasites." The multidisciplinary implications for crucial aspects of the disease should therefore lead the present baseline update to be taken into account in future research studies.
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Symbionts do not affect the mating incompatibility between the Brazilian-1 and Peruvian morphotypes of the Anastrepha fraterculus cryptic species complex. Sci Rep 2019; 9:18319. [PMID: 31797888 PMCID: PMC6893037 DOI: 10.1038/s41598-019-54704-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/14/2019] [Indexed: 11/11/2022] Open
Abstract
The South American fruit fly, Anastrepha fraterculus, is clearly undergoing a speciation process. Among others, two of their morphotypes, the Brazilian-1 and Peruvian, have accumulated differences in pre- and post-zygotic mechanisms resulting in a degree of reproductive isolation. Both harbor a different strain of Wolbachia, which is a widespread endosymbiotic bacterium among many invertebrates producing a range of reproductive effects. In this paper, we studied the role of this bacterium as one of the factors involved in such isolation process. Infected and cured laboratory colonies were used to test pre- and post-zygotic effects, with special emphasis in uni- and bi-directional cytoplasmic incompatibility (CI). We showed that Wolbachia is the only known reproductive symbiont present in these morphotypes. Wolbachia reduced the ability for embryonic development in crosses involving cured females and infected males within each morphotype (uni-directional CI). This inhibition showed to be more effective in the Peruvian morphotype. Bi-directional CI was not evidenced, suggesting the presence of compatible Wolbachia strains. We conclude that Wolbachia is not directly involved in the speciation process of these morphotypes. Other mechanisms rather than CI should be explored in order to explain the reduced mating compatibility between the Brazilian-1 and Peruvian morphotypes.
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The rpl23 gene and pseudogene are hotspots of illegitimate recombination in barley chloroplast mutator seedlings. Sci Rep 2019; 9:9960. [PMID: 31292475 PMCID: PMC6620283 DOI: 10.1038/s41598-019-46321-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 06/26/2019] [Indexed: 11/23/2022] Open
Abstract
Previously, through a TILLING (Targeting Induced Local Lesions in Genomes) approach applied on barley chloroplast mutator (cpm) seedlings a high frequency of polymorphisms in the rpl23 gene was detected. All the polymorphisms corresponded to five differences already known to exist in nature between the rpl23 gene located in the inverted repeats (IRs) and the rpl23 pseudogene located in the large single copy region (LSC). In this investigation, polymorphisms in the rpl23 gene were verified and besides, a similar situation was found for the pseudogene in cpm seedlings. On the other hand, no polymorphisms were found in any of those loci in 40 wild type barley seedlings. Those facts and the independent occurrence of polymorphisms in the gene and pseudogene in individual seedlings suggest that the detected polymorphisms initially arose from gene conversion between gene and pseudogene. Moreover, an additional recombination process involving small recombinant segments seems to occur between the two gene copies as a consequence of their location in the IRs. These and previous results support the hypothesis that the CPM protein is a component of the plastome mismatch repair (MMR) system, whose failure of the anti-recombination activity results in increased illegitimate recombination between the rpl23 gene and pseudogene.
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