ABSTRACT
Mangroves are an important part of coastal and estuarine ecosystems where they serve as nurseries for marine species and prevent coastal erosion. Here we report the genome of Sonneratia ovata, which is a true mangrove that grows in estuarine environments and can tolerate moderate salt exposure. We sequenced the S. ovata genome and assembled it into chromosome-level scaffolds through the use of Hi-C. The genome is 212.3 Mb and contains 12 chromosomes that range in size from 12.2 to 23.2 Mb. Annotation identified 29,829 genes with a BUSCO completeness of 95.9%. We identified salt genes and found copy number expansion of salt genes such as ADP-ribosylation factor 1, and elongation factor 1-alpha. Population analysis identified a low level of genetic variation and a lack of population structure within S. ovata.
Subject(s)
Genome, Plant , Molecular Sequence Annotation , Genetics, PopulationABSTRACT
A population of chromosome segment substitution lines was developed using KDML105 as the recurrent parent and one of DH212 (IR68586-F2-CA-143) or DH103 (IR68586-F2-CA-31) as the donor parent. The donor parents are part of a doubled haploid population from a cross between CT9993, an upland japonica accession, and IR62266, a lowland indica accession. Multiple QTL that are relevant to drought avoidance, drought tolerance and yield traits under drought stress were mapped in this doubled haploid population and the segments selected for the chromosome segment substitution lines were chosen to capture these QTL. The chromosome segment substitution line population was phenotyped under irrigated and mild drought stress conditions, which identified that many yield traits under drought stress had been introduced into the chromosome segment substitution lines.
Subject(s)
Droughts , Oryza , Chromosome Mapping , Oryza/genetics , Phenotype , Quantitative Trait LociABSTRACT
Rice is an important crop that is consumed by approximately half of the world's population on a regular basis. Plant height is an important characteristic with shorter rice often having higher lodging resistance and better soil nutrient utilization allowing for lower fertilizer use. We used a Chromosome Segment Substitution Line (CSSL) population generated by introgressing segments of CT9993 and IR62266 into KDML 105. We identified height QTLs on chromosomes 1 and 4. We performed whole genome sequencing of the parental lines and found that IR62266 has the deletion in Gibberellin 20-oxidase 2 corresponding to the semi-dwarf 1 locus. However, short height on chromosome 1 came from CT9993 with no mutation in Gibberellin 20-oxidase 2, or any known height genes. The height QTL on chromosome 4 contains mutations in Peroxisome biogenesis protein 6, which has been linked to a reduced growth phenotype in A. thaliana, making this a good candidate height gene.
Subject(s)
Oryza , Chromosome Mapping , Chromosomes, Plant/genetics , Oryza/genetics , Phenotype , Quantitative Trait LociABSTRACT
Mangroves are plants that live in tropical and subtropical coastal regions of the world, they are adapted to high salt environments and cyclic tidal flooding. Mangroves play important ecological roles, including acting as breeding grounds for many fish species and to prevent coastal erosion. The genomes of three mangrove species, Bruguiera gymnorhiza, Bruguiera cylindrica, and a hybrid of the two, Bruguiera hainesii were sequenced, assembled and annotated. The two progenitor species, B. gymnorhiza and B. cylindrica, were found to be highly similar to each other and sufficiently similar to B. parviflora to allow it to be used for reference based scaffolding to generate chromosome level scaffolds. The two subgenomes of B. hainesii were independently assembled and scaffolded. Analysis of B. hainesii confirms that it is a hybrid and the hybridisation event was estimated at 2.4 to 3.5 million years ago using a Bayesian Relaxed Molecular Clock approach.
Subject(s)
Rhizophoraceae , Animals , Rhizophoraceae/genetics , Bayes Theorem , Plant BreedingABSTRACT
Importance: Hereditary hemochromatosis is predominantly caused by the HFE p.C282Y homozygous pathogenic variant. Liver carcinoma and mortality risks are increased in individuals with clinically diagnosed hereditary hemochromatosis, but risks are unclear in mostly undiagnosed p.C282Y homozygotes identified in community genotyping. Objective: To estimate the incidence of primary hepatic carcinoma and death by HFE variant status. Design, Setting, and Participants: Cohort study of 451â¯186 UK Biobank participants of European ancestry (aged 40-70 years), followed up from baseline assessment (2006-2010) until January 2018. Exposures: Men and women with HFE p.C282Y and p.H63D genotypes compared with those with neither HFE variants. Main Outcomes and Measures: Two linked co-primary outcomes (incident primary liver carcinoma and death from any cause) were ascertained from follow-up via hospital inpatient records, national cancer registry, and death certificate records, and from primary care data among a subset of participants for whom data were available. Associations between genotype and outcomes were tested using Cox regression adjusted for age, assessment center, genotyping array, and population genetics substructure. Kaplan-Meier lifetable probabilities of incident diagnoses were estimated from age 40 to 75 years by HFE genotype and sex. Results: A total of 451â¯186 participants (mean [SD] age, 56.8 [8.0] years; 54.3% women) were followed up for a median (interquartile range) of 8.9 (8.3-9.5) years. Among the 1294 male p.C282Y homozygotes, there were 21 incident hepatic malignancies, 10 of which were in participants without a diagnosis of hemochromatosis at baseline. p.C282Y homozygous men had a higher risk of hepatic malignancies (hazard ratio [HR], 10.5 [95% CI, 6.6-16.7]; P < .001) and all-cause mortality (n = 88; HR, 1.2 [95% CI, 1.0-1.5]; P = .046) compared with men with neither HFE variant. In lifetables projections for male p.C282Y homozygotes to age 75 years, the risk of primary hepatic malignancy was 7.2% (95% CI, 3.9%-13.1%), compared with 0.6% (95% CI, 0.4%-0.7%) for men with neither variant, and the risk of death was 19.5% (95% CI, 15.8%-24.0%), compared with 15.1% (95% CI, 14.7%-15.5%) among men with neither variant. Among female p.C282Y homozygotes (n = 1596), there were 3 incident hepatic malignancies and 60 deaths, but the associations between homozygosity and hepatic malignancy (HR, 2.1 [95% CI, 0.7-6.5]; P = .22) and death (HR, 1.2 [95% CI, 0.9-1.5]; P = .20) were not statistically significant. Conclusions and Relevance: Among men with HFE p.C282Y homozygosity, there was a significantly increased risk of incident primary hepatic malignancy and death compared with men without p.C282Y or p.H63D variants; there was not a significant association for women. Further research is needed to understand the effects of early diagnosis and treatment.
Subject(s)
Hemochromatosis Protein/genetics , Hemochromatosis/genetics , Homozygote , Liver Neoplasms/etiology , Mutation , Adult , Aged , Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Biological Specimen Banks , Cohort Studies , Female , Genotyping Techniques , Hemochromatosis/blood , Hemochromatosis/complications , Hemochromatosis/mortality , Humans , Male , Middle Aged , Polycythemia/etiology , Sex FactorsABSTRACT
Advances in genome technology have facilitated a new understanding of the historical and genetic processes crucial to rapid phenotypic evolution under domestication. To understand the process of dog diversification better, we conducted an extensive genome-wide survey of more than 48,000 single nucleotide polymorphisms in dogs and their wild progenitor, the grey wolf. Here we show that dog breeds share a higher proportion of multi-locus haplotypes unique to grey wolves from the Middle East, indicating that they are a dominant source of genetic diversity for dogs rather than wolves from east Asia, as suggested by mitochondrial DNA sequence data. Furthermore, we find a surprising correspondence between genetic and phenotypic/functional breed groupings but there are exceptions that suggest phenotypic diversification depended in part on the repeated crossing of individuals with novel phenotypes. Our results show that Middle Eastern wolves were a critical source of genome diversity, although interbreeding with local wolf populations clearly occurred elsewhere in the early history of specific lineages. More recently, the evolution of modern dog breeds seems to have been an iterative process that drew on a limited genetic toolkit to create remarkable phenotypic diversity.
Subject(s)
Animals, Domestic/genetics , Dogs/genetics , Genome/genetics , Haplotypes/genetics , Polymorphism, Single Nucleotide/genetics , Animals , Animals, Domestic/classification , Animals, Wild/classification , Animals, Wild/genetics , Breeding , Computational Biology , Dogs/classification , Evolution, Molecular , Asia, Eastern/ethnology , Middle East/ethnology , Phenotype , Phylogeny , Wolves/classification , Wolves/geneticsABSTRACT
BACKGROUND: Uptake and adherence to cardiac rehabilitation (CR) are low, and a contributing factor to this may be the practical difficulties of providing a tailored CR environment suited to individual preferences and needs. OBJECTIVE: The aim of this study was to develop and test a short questionnaire that CR practitioners can use to understand individual patient need and tailor support accordingly. METHODS: A conceptual framework of engagement in CR was derived from a comprehensive literature review and the content analysis of semistructured interviews with 15 CR patients. The conceptual framework was used to construct the first version of the Cardiac Rehabilitation Inventory (CRI), which comprised 42 items. Responses on the CRI were measured using a 5-point Likert scale. The CRI was administered to 380 phase III and IV CR patients, and factor analysis (FA) was used to identify salient CR engagement factors. RESULTS: The simplest structure found using FA was three 6-item subscales that all had good levels of internal consistency (Cronbach's α) and were labeled (a) outcome anxiety, α = .726; (2) process anxiety, α = .724; and (3) autonomy, α = .653. The 3-factor CRI model was verified using confirmatory FA (CMin/df = 3.2, root-mean-square error of approximation = 0.073). Attenders were found to have higher levels of outcome anxiety than nonattenders (P < .001), and precontemplator nonattenders were found to have lower autonomy compared with attenders (P < .001). Standard multiple regression analysis indicated outcome anxiety was a strong predictor of CR intentions (r = 0.716), followed by autonomy (r = 0.110) and process anxiety (r = 0.031). CONCLUSIONS: The CRI is a reliable method of measuring CR outcome anxiety, process anxiety, and autonomy. These CRI measurements provide rehabilitation practitioners with valuable information that can help provide individual tailored support.
Subject(s)
Attitude to Health , Heart Diseases/psychology , Heart Diseases/rehabilitation , Patient Compliance/psychology , Self Efficacy , Exercise Therapy/psychology , Female , Humans , Male , Needs Assessment , Patient Education as Topic , Patient Satisfaction , Quality of Life/psychology , Surveys and QuestionnairesABSTRACT
Oil palm has become one of the most important oil crops in the world. Marker-assisted selections have played a pivotal role in oil palm breeding programs. Here, we report the use of genotyping-by-sequencing (GBS) approach for a large-scale SNP discovery and genotyping of a mapping population. Reduced representation libraries of 108 F2 progeny were sequenced and a total of 524 million reads were obtained. We detected 21,471 single nucleotide substitutions, most of which (62.6%) represented transition events. Of 3417 fully informative SNP markers, we were able to place 1085 on a linkage map, which spanned 1429.6 cM and had an average of one marker every 1.26 cM. Three QTL affecting trunk height were detected on LG 10, 14 and 15, whereas a single QTL associated with fruit bunch weight was identified on LG 3. The use of GBS approach proved to be rapid, cost-effective and highly reproducible in this species.
Subject(s)
Genome, Plant , Genotype , Plant Oils/economics , Polymorphism, Single Nucleotide , Quantitative Trait Loci , Trees/genetics , Molecular Sequence Data , Palm OilABSTRACT
The aim of this study was to investigate whether playing rugby at altitude or after travel (domestic and international) disadvantaged teams. In a retrospective longitudinal study, all matches (N = 125) played in the 2012 Super Rugby Competition were analyzed for key performance indicators (KPI) from coded game data provided by OPTA sports data company. Matches were played in a home-away format in New Zealand, South Africa, and Australia. Teams based at sea level but playing at altitude (1,271-1,753 m) were more likely to miss tackles (mean ± 90% confidence interval, 1.4 ± 1.7) and score fewer points in the first half compared with games at sea level. In the second half of games, sea level teams at altitude were very likely to make fewer gain lines (-4.0 ± 2.7) compared with the second half of games at sea level. The decreased ability to break the defensive line, which may be the result of altitude-induced fatigue, could reduce the likelihood of scoring points and winning a game. Travel also had an effect on KPI, where international travel resulted in more missed tackles (1.7 ± 1.3) and less frequent gain lines (-3.0 ± 1.9) in the first half relative to matches at home; overall, away teams (domestic and international) scored 4 less points in the second half compared with home teams. In conclusion, playing away from home in another country, particularly at altitude, can have a detrimental effect on KPI, which may affect the overall performance and the chances of winning matches.
Subject(s)
Altitude , Athletic Performance/physiology , Football/physiology , Travel , Fatigue/physiopathology , Humans , Longitudinal Studies , Male , Retrospective StudiesABSTRACT
BACKGROUND: The rubber tree, Hevea brasiliensis, is an important plant species that is commercially grown to produce latex rubber in many countries. The rubber tree variety BPM 24 exhibits cytoplasmic male sterility, inherited from the variety GT 1. RESULTS: We constructed the rubber tree mitochondrial genome of a cytoplasmic male sterile variety, BPM 24, using 454 sequencing, including 8 kb paired-end libraries, plus Illumina paired-end sequencing. We annotated this mitochondrial genome with the aid of Illumina RNA-seq data and performed comparative analysis. We then compared the sequence of BPM 24 to the contigs of the published rubber tree, variety RRIM 600, and identified a rearrangement that is unique to BPM 24 resulting in a novel transcript containing a portion of atp9. CONCLUSIONS: The novel transcript is consistent with changes that cause cytoplasmic male sterility through a slight reduction to ATP production efficiency. The exhaustive nature of the search rules out alternative causes and supports previous findings of novel transcripts causing cytoplasmic male sterility.
Subject(s)
Genome, Mitochondrial/genetics , Hevea/genetics , Adenosine Triphosphate , Gene Expression Regulation, Plant , Hevea/metabolism , Hevea/physiology , Plant Proteins/genetics , Plant Proteins/metabolismABSTRACT
Elaeis guineensis (oil palm) accounts for a large and increasing proportion of the world's cooking oil production. Cloning via somatic embryogenesis results in a somaclonal variant known as mantled which produce fruit with little to no oil yield. The mantled phenotype is believed to be epigenetic in nature. We performed RNA-Seq on developing flower and fruit samples of normal and mantled oil palm to characterize their transcriptomes. We present expression data for all transcripts in normal and mantled flower and fruit samples. Many genes are differentially expressed, including several from pathways that may be the cause of the mantled phenotype if disrupted, such as genes involved in primary hormone responses, DNA replication and repair, chromatin remodeling and a gene involved in RNA mediated DNA methylation. In addition, the gene expression data for developing flower and fruit will serve as a valuable resource for oil palm genetics and genomic studies.
Subject(s)
Arecaceae/metabolism , Flowers/metabolism , Fruit/metabolism , Plant Proteins/genetics , Transcriptome , Arecaceae/genetics , Flowers/genetics , Fruit/genetics , Gene Expression Profiling , Gene Expression Regulation, Plant , Molecular Sequence Annotation , Phenotype , Plant Proteins/metabolismABSTRACT
OBJECTIVES: HFE haemochromatosis genetic variants have an uncertain clinical penetrance, especially to older ages and in undiagnosed groups. We estimated p.C282Y and p.H63D variant cumulative incidence of multiple clinical outcomes in a large community cohort. DESIGN: Prospective cohort study. SETTING: 22 assessment centres across England, Scotland, and Wales in the UK Biobank (2006-2010). PARTICIPANTS: 451 270 participants genetically similar to the 1000 Genomes European reference population, with a mean of 13.3-year follow-up through hospital inpatient, cancer registries and death certificate data. MAIN OUTCOME MEASURES: Cox proportional HRs of incident clinical outcomes and mortality in those with HFE p.C282Y/p.H63D mutations compared with those with no variants, stratified by sex and adjusted for age, assessment centre and genetic stratification. Cumulative incidences were estimated from age 40 years to 80 years. RESULTS: 12.1% of p.C282Y+/+ males had baseline (mean age 57 years) haemochromatosis diagnoses, with a cumulative incidence of 56.4% at age 80 years. 33.1% died vs 25.4% without HFE variants (HR 1.29, 95% CI: 1.12 to 1.48, p=4.7×10-4); 27.9% vs 17.1% had joint replacements, 20.3% vs 8.3% had liver disease, and there were excess delirium, dementia, and Parkinson's disease but not depression. Associations, including excess mortality, were similar in the group undiagnosed with haemochromatosis. 3.4% of women with p.C282Y+/+ had baseline haemochromatosis diagnoses, with a cumulative incidence of 40.5% at age 80 years. There were excess incident liver disease (8.9% vs 6.8%; HR 1.62, 95% CI: 1.27 to 2.05, p=7.8×10-5), joint replacements and delirium, with similar results in the undiagnosed. p.C282Y/p.H63D and p.H63D+/+ men or women had no statistically significant excess fatigue or depression at baseline and no excess incident outcomes. CONCLUSIONS: Male and female p.C282Y homozygotes experienced greater excess morbidity than previously documented, including those undiagnosed with haemochromatosis in the community. As haemochromatosis diagnosis rates were low at baseline despite treatment being considered effective, trials of screening to identify people with p.C282Y homozygosity early appear justified.
Subject(s)
Delirium , Hemochromatosis , Liver Diseases , Adult , Aged, 80 and over , Female , Humans , Male , Middle Aged , Biological Specimen Banks , Delirium/complications , Genotype , Hemochromatosis/diagnosis , Hemochromatosis/epidemiology , Hemochromatosis/genetics , Hemochromatosis Protein/genetics , Histocompatibility Antigens Class I/genetics , Homozygote , Liver Diseases/complications , Mutation , Prospective Studies , UK Biobank , AgedABSTRACT
The aim was to investigate the effects of low-load resistant training combined with vascular occlusion or normobaric hypoxic exposure, on neuromuscular function. In a randomised controlled trial, well-trained athletes took part in a 5-week training of knee flexor/extensor muscles in which low-load resistant exercise (20% of one repetition maximum, 1-RM) was combined with either (1) an occlusion pressure of approximately 230 mmHg (KT, n = 10), (2) hypoxic air to generate an arterial blood oxygen saturation of ~80% (HT, n = 10), or (3) with no additional stimulus (CT, n = 10). Before and after training, participants completed the following tests: 3-s maximal voluntary contraction (MVC3), 30-s MVC, and an endurance test (maximal number of repetitions at 20% 1-RM, Reps20). Electromyographic activity (root mean square, RMS) was measured during tests and the cross-sectional area (CSA) of the quadriceps and hamstrings was measured pre- and post-training. Relative to CT, KT, and HT showed likely increases in MVC3 (11.0 ± 11.9 and 15.0 ± 13.1%, mean ± 90% confidence interval), MVC30 (10.2 ± 9.0 and 18.3 ± 17.4%), and Reps20 (28.9 ± 23.7 and 23.3 ± 24.0%). Compared to the CT group, CSA increased in the KT (7.6 ± 5.8) and HT groups (5.3 ± 3.0). KT had a large effect on RMS during MVC3, compared to CT (effect size 0.8) and HT (effect size 0.8). We suspect hypoxic conditions created within the muscles during vascular occlusion and hypoxic training may play a key role in these performance enhancements.
Subject(s)
Hypoxia/physiopathology , Muscle Contraction , Muscle, Skeletal/physiology , Oxygen Consumption , Resistance Training , Athletes , Case-Control Studies , Female , Humans , Muscle, Skeletal/blood supply , Muscle, Skeletal/innervation , Oxygen/blood , Physical Endurance , Regional Blood Flow , Young AdultABSTRACT
The aim of this study was to investigate whether wearing compression garments during recovery improved subsequent repeated sprint and 3-km run performance. In a randomized single-blind crossover study, 22 well-trained male rugby union players (mean ± SD: age 20.1 ± 2.1 years, body mass 88.4 ± 8.8 kg) were given a full-leg length compressive garment (76% Meryl Elastane, 24% Lycra) or a similar-looking noncompressive placebo garment (92% Polyamide, 8% Lycra) to wear continuously for 24 hours after performing a series of circuits developed to simulate a rugby game. After the 24-hour recovery, garments were removed and a 40-m repeated sprint test (10 sprints at 30-second intervals), followed 10 minutes later by a 3-km run, was completed. One week later, the groups were reversed and testing repeated. Relative to the placebo, wearing the compressive garment decreased time to complete the 3 km by 2.0% ± 1.9% (mean ± 90% confidence interval). Additionally, average sprint times improved (1.2% ± 1.5%) and fatigue was diminished (-15.8% ± 26.1%) during the repeated sprint test in the compression group compared with the placebo group. Delayed onset muscle soreness was substantially lower in the compression group compared with the placebo group, 48 hours after testing. Wearing compressive garments during recovery is likely to be worthwhile, and very unlikely to be harmful for well-trained rugby union players.
Subject(s)
Athletic Performance/physiology , Clothing , Football/physiology , Running/physiology , Sports Equipment , Adolescent , Adult , Creatine Kinase/blood , Cross-Over Studies , Humans , Male , Muscle Fatigue , Muscle, Skeletal/physiology , Musculoskeletal Pain/etiology , Pressure , Single-Blind Method , Young AdultABSTRACT
Sugarcane accounts for a large portion of the worlds sugar production. Modern commercial cultivars are complex hybrids of S. officinarum, S. spontaneum, and several other Saccharum species, resulting in an auto-allopolyploid with 8-12 copies of each chromosome. The current genome assembly gold standard is to generate a long read assembly followed by chromatin conformation capture sequencing to scaffold. We used the PacBio RSII and chromatin conformation capture sequencing to sequence and assemble the genome of a South East Asian commercial sugarcane cultivar, known as Khon Kaen 3. The Khon Kaen 3 genome assembled into 104,477 contigs totalling 7 Gb, which scaffolded into 56 pseudochromosomes containing 5.2 Gb of sequence. Genome annotation produced 242,406 genes from 30,927 orthogroups. Aligning the Khon Kaen 3 genome sequence to S. officinarum and S. spontaneum revealed a high level of apparent recombination, indicating a chimeric assembly. This assembly error is explained by high nucleotide identity between S. officinarum and S. spontaneum, where 91.8% of S. spontaneum aligns to S. officinarum at 94% identity. Thus, the subgenomes of commercial sugarcane are so similar that using short reads to correct long PacBio reads produced chimeric long reads. Future attempts to sequence sugarcane must take this information into account.
Subject(s)
Saccharum , Saccharum/genetics , Thailand , Chromatin , Edible Grain , Sequence Analysis, DNAABSTRACT
BACKGROUND: Trapped Neutrophil Syndrome (TNS) is a common autosomal recessive neutropenia in Border collie dogs. RESULTS: We used a candidate gene approach and linkage analysis to show that the causative gene for TNS is VPS13B. We chose VPS13B as a candidate because of similarities in clinical signs between TNS and Cohen syndrome, in human, such as neutropenia and a typical facial dysmorphism. Linkage analysis using microsatellites close to VPS13B showed positive linkage of the region to TNS. We sequenced each of the 63 exons of VPS13B in affected and control dogs and found that the causative mutation in Border collies is a 4 bp deletion in exon 19 of the largest transcript that results in premature truncation of the protein. Cohen syndrome patients present with mental retardation in 99% of cases, but learning disabilities featured in less than half of TNS affected dogs. It has been implied that loss of the alternate transcript of VPS13B in the human brain utilising an alternate exon, 28, may cause mental retardation. Mice cannot be used to test this hypothesis as they do not express the alternate exon. We show that dogs do express alternate transcripts in the brain utilising an alternate exon homologous to human exon 28. CONCLUSION: Dogs can be used as a model organism to explore the function of the alternately spliced transcript of VPS13B in the brain. TNS in Border collies is the first animal model for Cohen syndrome and can be used to study the disease aetiology.
Subject(s)
Disease Models, Animal , Intellectual Disability/genetics , Microcephaly/genetics , Muscle Hypotonia/genetics , Myopia/genetics , Neutropenia/genetics , Obesity/genetics , Amino Acid Sequence , Animals , Base Sequence , Developmental Disabilities/genetics , Developmental Disabilities/physiopathology , Dog Diseases/genetics , Dog Diseases/physiopathology , Dogs , Exons/genetics , Fingers/abnormalities , Fingers/physiopathology , Genetic Linkage , Genotype , Humans , Intellectual Disability/physiopathology , Mice , Microcephaly/physiopathology , Molecular Sequence Data , Muscle Hypotonia/physiopathology , Myopia/physiopathology , Neutropenia/physiopathology , Neutropenia/veterinary , Obesity/physiopathology , Retinal Degeneration , Sequence Analysis , Syndrome , Vesicular Transport Proteins/chemistry , Vesicular Transport Proteins/geneticsABSTRACT
BACKGROUND: Thailand is a country with large diversity in rice varieties due to its rich and diverse ecology. In this paper, 300 rice accessions from all across Thailand were sequenced to identify SNP variants allowing for the population structure to be explored. RESULTS: The result of inferred population structure from admixture and clustering analysis illustrated strong evidence of substructure in each geographical region. The results of phylogenetic tree, PCA analysis, and machine learning on population identifying SNPs also supported the inferred population structure. CONCLUSION: The population structure inferred in this study contains five subpopulations that tend to group individuals based on location. So, each subpopulation has unique genetic patterns, agronomic traits, as well as different environmental conditions. This study can serve as a reference point of the nation-wide population structure for supporting breeders and researchers who are interested in Thai rice.
ABSTRACT
Bruguiera is a genus of true mangroves that are mostly distributed in the Indo-West Pacific region. However, the number of published whole chloroplast genome sequences of Bruguiera species are limited. Here, the complete chloroplast sequences of five Bruguiera species were sequenced and assembled using Illumina data. The chloroplast genomes of B. gymnorhiza, B. hainesii, B. cylindrica, B. parviflora and B. sexangula were assembled into 161,195, 164,295, 164,297, 163,228 and 164,170 bp, respectively. All chloroplast genomes contain 37 tRNA and eight rRNA genes, with either 84 or 85 protein-coding genes. A comparative analysis of these genomes revealed high similarity in gene structure, gene order and boundary position of the LSC, SSC and two IR regions. Interestingly, B. gymnorhiza lost a rpl32 gene in the SSC region. In addition, a ndhF gene in B. parviflora straddles both the SSC and IRB boundary regions. These genes reveal differences in chloroplast evolution among Bruguiera species. Repeats and SSRs in the chloroplast genome sequences were found to be highly conserved between B. cylindrica and B. hainesii as well as B. gymnorhiza and B. sexangula indicating close genetic relationships based on maternal inheritance. Notably, B. hainesii, which is considered a hybrid between B. gymnorhiza and B. cylindrica, appears to have inherited the chloroplast from B. cylindrica. Investigating the effects of selection events on shared protein-coding genes showed a positive selection in rps7 and rpl36 genes in all species compared to land-plant species. A phylogenetic analysis, based on 59 conserved chloroplast protein-coding genes, showed strong support that all Bruguiera species are in the clade Rhizophoraceae. This study provides valuable genetic information for the study of evolutionary relationships and population genetics in Bruguiera and other mangrove species.
ABSTRACT
We have assembled the complete sequence of the Durio zibethinus chloroplast genome using long PacBio reads. Durian is a valuable commercial tree that produces durian fruit, which is popular in Southeast Asia. The chloroplast genome assembled into a single 143 kb cyclic contig that contained 111 genes. There were 46 short direct repeats (45 to 586 bp) and five short inverted repeats (63 to 169 bp). The long reads that were used for the assembly span the entire chloroplast with > 10 kb overlaps and multiple long reads join the start of the contig to the end of the contig. The durian chloroplast was found to lack the large inverted repeat that is common in chloroplast genomes. An additional 24 durian varieties were sequenced and compared to the assembly and found to also lack the large inverted repeat. There were nine SNPs among the varieties.