ABSTRACT
Background: Maternally inherited chromosomal duplications in the region of 15q11.2q13.1 have been associated with neurodevelopmental disorders and other clinical manifestations. Prenatal diagnosis of such duplications is crucial for providing accurate genetic counseling and guiding clinical management decisions. Objective: This study aims to present the prenatal diagnosis and genetic counseling of a maternally inherited 15q11.2q13.1 duplication. Case Presentation: A 38-year-old gravida 1, para 0 woman underwent amniocentesis at 16 weeks of gestation due to advanced maternal age. Karyotype analysis was performed on cultured amniocytes, and chromosomal microarray analysis (CMA) was conducted on uncultured amniocytes. Results: The karyotype analysis of the cultured amniocytes revealed a normal karyotype of 46, XX. CMA identified a 4.21 Mb maternally inherited chromosomal duplication in the region of 15q11.2q13.1 (arr[GRCh37]15q11.2q13.1(23,894,550_28,107,154)x3). Conclusions: Copy number variants (CNVs) and unbalanced chromosomal abnormalities (UBCA) identified in prenatal cases require careful consideration and accurate interpretation to determine their potential harm or harmlessness compared to the norm. The combination of prenatal ultrasound, karyotype analysis, CMA, and genetic counseling proves helpful in the prenatal diagnosis of CNVs and UBCA.
Subject(s)
Chromosome Duplication , Genetic Counseling , Pregnancy , Female , Humans , Adult , East Asian People , Maternal Inheritance , Mosaicism , Prenatal Diagnosis , KaryotypeABSTRACT
Abstract Allium sativum L. is an herb of the Alliaceae family with a specific taste and aroma and medicinal and nutraceutical properties that are widely marketed in several countries. Brazil is one of the largest importers of garlic in the world, despite of its production is restricted and limited to internal consumption. Thus, explore the genetic diversity of commercial garlic conserved at germplasm banks is essential to generate additional genetic information about its economically important crop. A suitable tool for this purpose is the cytogenetic characterisation of these accessions. This study aimed to characterise the cytogenetic diversity among seven accessions of garlic from a Germplasm Bank in Brazil. The karyotypes were obtained by conventional staining and with chromomycin A3 (CMA) and 4,6-diamidino-2-phenylindole (DAPI) fluorochromes. All accessions analysed showed chromosome number 2n = 16, karyotype formula 6M+2SM, symmetrical karyotypes, reticulate interphase nuclei, and chromosomes with uniform chromatin condensation from prophase to metaphase. The fluorochromes staining showed differences in the amount and distribution of heterochromatin along the chromosomes and between accessions studied. Based on the distribution pattern of these small polymorphisms, it was possible to separate the seven accessions into three groups. It was also possible to differentiate some of the accessions individually. One of the results obtained showed a heteromorphic distension of the nucleolar organiser region observed on the chromosome pairs 6 or 7 with peculiar characteristics. It was suggested for example, that the heteromorphic block of heterochromatin (CMA+++/DAPI-) on chromosome 6 of the "Branco Mineiro Piauí" accession can be used as a marker to identify this genotype or may be associated with some character of economic interest.
Resumo Allium sativum L. é uma erva da família Alliaceae com sabor e aroma específicos e propriedades medicinais e nutracêuticas amplamente comercializada em diversos países. O Brasil é um dos maiores importadores de alho do mundo, apesar da sua produção ser restrita e limitada ao consumo interno. Assim, explorar a diversidade genética do alho comercial conservado em bancos de germoplasma é essencial para fornecer informações genéticas adicionais acerca dessa cultura economicamente importante. Uma ferramenta adequada para esse fim é a caracterização citogenética desses acessos. Este estudo teve como objetivo caracterizar a diversidade citogenética entre sete acessos de alho de um Banco de Germoplasma no Brasil. Os cariótipos foram obtidos por coloração convencional e com os fluorocromos de cromomicina A3 (CMA) e 4,6-diamidino-2-fenilindol (DAPI). Todos os acessos analisados apresentaram número cromossômico 2n = 16, fórmula cariotípica 6M + 2SM, cariótipos simétricos, núcleos reticulados em intérfase e cromossomos com condensação uniforme da cromatina da prófase para a metáfase. A coloração com fluorocromos mostrou diferenças na quantidade e distribuição de heterocromatina ao longo dos cromossomos e entre os acessos estudados. Com base no padrão de distribuição desses pequenos polimorfismos, foi possível separar os sete acessos em três grupos. Também foi possível diferenciar individualmente alguns dos acessos. Um dos resultados obtidos mostrou distensão heteromórfica da região organizadora nucleolar observada nos pares dos cromossomos 6 ou 7 com características peculiares. Foi sugerido, por exemplo, que o bloco heteromórfico de heterocromatina (CMA +++ / DAPI-) no cromossomo 6 do acesso "Branco Mineiro Piauí" pode ser usado como um marcador para identificar esse genótipo ou pode estar associado a algum caráter de interesse econômico.
Subject(s)
Garlic , Brazil , Heterochromatin/genetics , Chromosome Banding , Karyotype , KaryotypingABSTRACT
Natural isolates of the potato and tomato pathogen Phytophthora infestans exhibit substantial variation in virulence, chemical sensitivity, ploidy, and other traits. A chromosome-scale assembly was developed to expand genomic resources for this oomyceteous microbe, and used to explore the basis of variation. Using PacBio and Illumina data, a long-range linking library, and an optical map, an assembly was created and coalesced into 15 pseudochromosomes spanning 219 Mb using SNP-based genetic linkage data. De novo gene prediction combined with transcript evidence identified 19,981 protein-coding genes, plus about eight thousand tRNA genes. The chromosomes were comprised of a mosaic of gene-rich and gene-sparse regions plus very long centromeres. Genes exhibited a biased distribution across chromosomes, especially members of families encoding RXLR and CRN effectors which clustered on certain chromosomes. Strikingly, half of F1 progeny of diploid parents were polyploid or aneuploid. Substantial expression level polymorphisms between strains were identified, much of which could be attributed to differences in chromosome dosage, transposable element insertions, and adjacency to repetitive DNA. QTL analysis identified a locus on the right arm of chromosome 3 governing sensitivity to the crop protection chemical metalaxyl. Strains heterozygous for resistance often experienced megabase-sized deletions of that part of the chromosome when cultured on metalaxyl, increasing resistance due to loss of the sensitive allele. This study sheds light on diverse phenomena affecting variation in P. infestans and relatives, helps explain the prevalence of polyploidy in natural populations, and provides a new foundation for biologic and genetic investigations.
Subject(s)
Biological Products , Phytophthora infestans , Solanum tuberosum , Humans , Phytophthora infestans/genetics , DNA Transposable Elements , Solanum tuberosum/genetics , KaryotypeABSTRACT
MAIN CONCLUSION: Coffea karyotype organization and evolution has been uncovered by classical cytogenetics and cytogenomics. We revisit these discoveries and present new karyotype data. Coffea possesses ~ 124 species, including C. arabica and C. canephora responsible for commercial coffee production. We reviewed the Coffea cytogenetics, from the first chromosome counting, encompassing the karyotype characterization, chromosome DNA content, and mapping of chromosome portions and DNA sequences, until the integration with genomics. We also showed new data about Coffea karyotype. The 2n chromosome number evidenced the diploidy of almost all Coffea, and the C. arabica tetraploidy, as well as the polyploidy of other hybrids. Since then, other genomic similarities and divergences among the Coffea have been shown by karyotype morphology, nuclear and chromosomal C-value, AT and GC rich chromosome portions, and repetitive sequence and gene mapping. These cytogenomic data allowed us to know and understand the phylogenetic relations in Coffea, as well as their ploidy level and genomic origin, highlighting the relatively recent allopolyploidy. In addition to the euploidy, the role of the mobile elements in Coffea diversification is increasingly more evident, and the comparative analysis of their structure and distribution on the genome of different species is in the spotlight for future research. An integrative look at all these data is fundamental for a deeper understanding of Coffea karyotype evolution, including the key role of polyploidy in C. arabica origin. The 'Híbrido de Timor', a recent natural allotriploid, is also in the spotlight for its potential as a source of resistance genes and model for plant polyploidy research. Considering this, we also present some unprecedented results about the exciting evolutionary history of these polyploid Coffea.
Subject(s)
Coffea , Coffea/genetics , Coffee , Genomics , Karyotype , Phylogeny , PolyploidyABSTRACT
BACKGROUND: Artemisia selengensis is traditional Chinese medicine and phytochemical analysis indicated that A. selengensis contains essential oils, fatty acids and phenolic acids. The lack of reference genomic information may lead to tardiness in molecular biology research of A. selengensis. METHOD AND RESULTS: Karyotype analysis, genome survey, and genome assembly was employed to acquire information on the genome structure of A. selengensis. The chromosome number is 2n = 2x = 36, karyotype formula is 28 m + 8Sm, karyotype asymmetry coefficient is 58.8%, and karyotypes were symmetric to Stebbins' type 2A. Besides, the flow cytometry findings reported that the mean peak value of fluorescent intensity is 1,170,677, 2C DNA content is 12 pg and the genome size was estimated to be approximately 5.87 Gb. Furthermore, the genome survey generates 341,478,078 clean reads, unfortunately, after K-mer analysis, no significant peak can be observed, the heterozygosity, repetitive rate and genome size was unable to estimated. It is speculated that this phenomenon might be due to the complexity of genome structure. 37,266 contigs are preliminary assembled with Oxford Nanopore Technology (ONT) sequencing, totaling 804 Mb and GC content was 34.08%. The total length is 804,475,881 bp, N50 is 29,624 bp, and the largest contig length is 239,792 bp. CONCLUSION: This study reveals the preliminary information of genome size of A. selengensis. These findings may provide supportive information for sequencing and assembly of whole-genome sequencing and encourage the progress of functional gene discovery, genetic improvement, evolutionary study, and structural studies of A. selengensis.
Subject(s)
Artemisia/genetics , Base Composition/genetics , Genome Size/genetics , Genomics/methods , High-Throughput Nucleotide Sequencing/methods , Karyotype , Karyotyping/methods , Molecular Sequence Annotation/methods , Phylogeny , Sequence Analysis, DNA/methods , Whole Genome SequencingABSTRACT
The genus Dracaena is the main source of dragon's blood, which is a plant resin and has been used as traditional medicine since ancient times in different civilizations. However, the chromosome numbers and karyotypes present in this genus remain poorly understood. In this study, fluorescence in situ hybridization (FISH) using oligonucleotide probes for ribosomal DNAs (5S and 45S rDNA) and telomeric repeats (TTTAGGG)3 was applied to analyze 4 related species: Dracaena terniflora Roxb., Dracaena cambodiana Pierre ex Gagnep., Aizong (Dracaena sp.), and Dracaena cochinchinensis (Lour.) S.C. Chen. In all 4 species, both 5S and 45S rDNA showed hybridization signals in the paracentromeric region of a pair of chromosomes; the sizes of the 45S rDNA signals were larger than those of the 5S rDNA. Importantly, the telomeric repeat signals were located in the telomeric regions of almost all chromosomes. The results indicated that the chromosome number of all 4 Dracaena species is 2n = 40, and the lengths of the mitotic metaphase chromosomes range from 0.99 to 2.98 µm. Our results provide useful cytogenetic information, which will be beneficial to future studies in genome structure of the genus Dracaena.
Subject(s)
Chromosome Mapping/methods , Chromosomes, Plant/chemistry , Dracaena/genetics , Karyotype , Centromere , China , Dracaena/classification , In Situ Hybridization, Fluorescence/methods , Karyotyping/methods , Phylogeography , RNA, Ribosomal/genetics , RNA, Ribosomal, 5S/genetics , TelomereABSTRACT
Allium sativum L. is an herb of the Alliaceae family with a specific taste and aroma and medicinal and nutraceutical properties that are widely marketed in several countries. Brazil is one of the largest importers of garlic in the world, despite of its production is restricted and limited to internal consumption. Thus, explore the genetic diversity of commercial garlic conserved at germplasm banks is essential to generate additional genetic information about its economically important crop. A suitable tool for this purpose is the cytogenetic characterisation of these accessions. This study aimed to characterise the cytogenetic diversity among seven accessions of garlic from a Germplasm Bank in Brazil. The karyotypes were obtained by conventional staining and with chromomycin A3 (CMA) and 4,6-diamidino-2-phenylindole (DAPI) fluorochromes. All accessions analysed showed chromosome number 2n = 16, karyotype formula 6M+2SM, symmetrical karyotypes, reticulate interphase nuclei, and chromosomes with uniform chromatin condensation from prophase to metaphase. The fluorochromes staining showed differences in the amount and distribution of heterochromatin along the chromosomes and between accessions studied. Based on the distribution pattern of these small polymorphisms, it was possible to separate the seven accessions into three groups. It was also possible to differentiate some of the accessions individually. One of the results obtained showed a heteromorphic distension of the nucleolar organiser region observed on the chromosome pairs 6 or 7 with peculiar characteristics. It was suggested for example, that the heteromorphic block of heterochromatin (CMA+++/DAPI-) on chromosome 6 of the "Branco Mineiro Piauí" accession can be used as a marker to identify this genotype or may be associated with some character of economic interest.
Subject(s)
Garlic , Brazil , Chromosome Banding , Heterochromatin/genetics , Karyotype , KaryotypingABSTRACT
A 46-year-old woman was diagnosed with acute promyelocytic leukemia (APL). The patient was given remission induction therapy with all-trans retinoic acid, and complete remission was achieved. Despite consolidation therapies with arsenic trioxide, daunorubicin and cytosine arabinoside (AraC), and gemtuzumab ozogamicin as well as maintenance therapy with tamibarotene, the patient experienced a relapse 6 months after the start of maintenance therapy. She was then given re-induction therapy with idarubicin+AraC and high-dose AraC, but remission was not achieved. Since the coordination of the unrelated donor had been completed at this time, she then underwent bone marrow transplantation with pre-conditioning of 4 Gy total body irradiation, fludarabine, and busulfan. However, on the 12th day after the transplantation, APL cells appeared in the peripheral blood and the disease progressed rapidly leading to the patient's death on the 15th day after the transplantation. APL usually has a good prognosis, and relapsed cases are often cured by autologous stem cell transplantation. However, this case was highly refractory to treatment and the patient deteriorated rapidly after the transplantation, suggesting a different pathogenesis from the usual from of APL.
Subject(s)
Antineoplastic Agents , Arsenicals , Hematopoietic Stem Cell Transplantation , Leukemia, Promyelocytic, Acute , Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Arsenicals/therapeutic use , Female , Humans , Karyotype , Leukemia, Promyelocytic, Acute/drug therapy , Leukemia, Promyelocytic, Acute/genetics , Middle Aged , Oxides/therapeutic use , Transplantation, Autologous , Treatment Outcome , Tretinoin/therapeutic useABSTRACT
Plant fertility is highly sensitive to elevated temperature. Here, we report that hot spells induce the formation of dyads and triads by disrupting the biogenesis or stability of the radial microtubule arrays (RMAs) at telophase II. Heat-induced meiotic restitution in Arabidopsis is predominantly SDR-type (Second Division Restitution) indicating specific interference with RMAs formed between separated sister chromatids. In addition, elevated temperatures caused distinct deviations in cross-over formation in male meiosis. Synapsis at pachytene was impaired and the obligate cross-over per chromosome was discarded, resulting in partial univalency in meiosis I (MI). At diakinesis, interconnections between non-homologous chromosomes tied separate bivalents together, suggesting heat induces ectopic events of non-homologous recombination. Summarized, heat interferes with male meiotic cross-over designation and cell wall formation, providing a mechanistic basis for plant karyotype change and genome evolution under high temperature conditions.
Subject(s)
Arabidopsis/growth & development , Chromosomes, Plant , Crossing Over, Genetic , DNA End-Joining Repair , Heat-Shock Response , Hot Temperature , Meiosis , Plants, Genetically Modified/growth & development , Arabidopsis/genetics , Arabidopsis/metabolism , Cell Wall/genetics , Cell Wall/metabolism , Evolution, Molecular , Gene Expression Regulation, Plant , Karyotype , Plants, Genetically Modified/genetics , Plants, Genetically Modified/metabolism , Pollen/genetics , Pollen/metabolismABSTRACT
Humans are inevitably exposed to bisphenol A (BPA) via multiple exposure ways. Thus, attention should be raised to the possible adverse effects related to low doses of BPA. Epidemiological studies have outlined BPA exposure and the increased risk of cardiovascular diseases (such as cardiac hypertrophy), which has been confirmed to be sex-specific in rodent animals and present in few in vitro studies, although the molecular mechanism is still unclear. However, whether BPA at low doses equivalent to human internal exposure level could induce cardiac hypertrophy via the calcineurin-DRP1 signaling pathway by disrupting calcium homeostasis is unknown. To address this, human embryonic stem cell (H1, XY karyotype and H9, XX karyotype)-derived cardiomyocytes (CM) were purified and applied to study the low-dose effects of BPA on cardiomyocyte hypertrophy. In our study, when H1- and H9-CM were exposed to noncytotoxic BPA (8 ng/ml), markedly elevated hypertrophic-related mRNA expression levels (such as NPPA and NPPB), enhanced cellular area and reduced ATP supplementation, demonstrated the hypertrophic cardiomyocyte phenotype in vitro. The excessive fission produced by BPA was promoted by CnAß-mediated dephosphorylation of DRP1. At the molecular level, the increase in cytosolic Ca2+ levels by low doses of BPA could discriminate between H1- and H9-CM, which may suggest a potential sex-specific hypertrophic risk in cardiomyocytes in terms of abnormal mitochondrial fission and ATP production by impairing CnAß-DRP1 signaling. In CnAß-knockdown cardiomyocytes, these changes were highly presented in XX-karyotyped cells, rather than in XY-karyotyped cells.
Subject(s)
Benzhydryl Compounds/toxicity , Cardiomyopathy, Hypertrophic/pathology , Estrogens, Non-Steroidal/toxicity , Mitochondria/drug effects , Myocytes, Cardiac/pathology , Phenols/toxicity , Calcineurin/genetics , Calcineurin/metabolism , Cardiomyopathy, Hypertrophic/chemically induced , Cell Differentiation , Dose-Response Relationship, Drug , Dynamins/metabolism , Gene Knockdown Techniques , Human Embryonic Stem Cells/physiology , Humans , Karyotype , Membrane Potential, Mitochondrial/drug effects , Mitochondria/pathology , Mitochondrial Dynamics/drug effects , Myocytes, Cardiac/cytology , Myocytes, Cardiac/drug effects , RNA, Small Interfering/metabolism , Sex Factors , Signal Transduction/drug effects , Signal Transduction/geneticsABSTRACT
The phenotypic, biochemical and genetic variability was studied in M2-M5 generations of ethyl methansulfonat (EMS, 0.2%) mutagenized rapeseed lines generated from canola, '00', B. napus cv. Vikros. EMS mutagenesis induced extensive diversity in morphological and agronomic traits among mutant progeny resulted in selection of EMS populations of B. napus- and B. rapa-morphotypes. The seeds of the obtained mutant lines were high-protein, low in oil and stabilized in contents of main fatty acids which make them useful for feed production. Despite the increased level of various meiotic abnormalities revealed in EMS populations, comparative karyotype analysis and FISH-based visualization of 45S and 5S rDNA indicated a high level of karyotypic stability in M2-M5 plants, and therefore, the obtained mutant lines could be useful in further rapeseed improvement. The revealed structural chromosomal reorganizations in karyotypes of several plants of B. rapa-type indicate that rapeseed breeding by chemical mutagenesis can result in cytogenetic instability in the mutant progeny, and therefore, it should include the karyotype examination. Our findings demonstrate that EMS at low concentrations has great potential in rapeseed improvement.
Subject(s)
Brassica napus/genetics , Genetic Variation , Genome, Plant , Mutagenesis/genetics , Mutation/genetics , Alleles , Brassica napus/anatomy & histology , Chromosomes, Plant/genetics , DNA, Ribosomal/genetics , Fatty Acids/analysis , Karyotype , Meiosis , Phenotype , Pollen/cytology , Pollen/ultrastructure , Seeds/metabolismABSTRACT
OBJECTIVE: To investigate the relation of blood arsenic concentration (BAC) with clinical effect and safety of arsenic-containing Qinghuang Powder (, QHP) in patients with myelodysplastic syndrome (MDS). METHODS: Totally 163 patients with MDS were orally treated with QHP for 2 courses of treatment, 3 months as 1 course. The BACs of patients were detected by atomic fluorescence spectrophotometry at 1, 3, and 6 months during the treatment, and the effective rate, hematological improvement and safety in patients after treatment with QHP were analyzed. RESULTS: After 2 courses of treatment, the total effective rate was 89.6% (146/163), with 31.3% (51/163) of hematological improvement and 58.3% (95/163) of stable disease. The hemoglobin increased from 73.48 ± 19.30 g/L to 80.39 ± 26.56 g/L (P<0.05), the absolute neutrophil count increased from 0.81 ± 0.48 × 109/L to 1.08 ± 0.62 × 109/L (P<0.05), and no significant changes were observed in platelet counts (P>0.05). Among 46 patients previously depended on blood transfusion, 28.3% (13/46) completely got rid of blood transfusion and 21.7% (10/46) reduced the volume of blood transfusion by more than 50% after treatment. The BACs were significantly increased in patients treated for 1 month with 32.17 ± 18.04 µ g/L (P<0.05), 3 months with 33.56 ± 15.28 µ g/L (P<0.05), and 6 months with 36.78 ± 11.92 µ g/L (P<0.05), respectively, as compared with those before treatment (4.08 ± 2.11 µ g/L). There were no significant differences of BACs among the patients treated for 1, 3 and 6 months (P>0.05). The adverse reactions of digestive tract during the treatment were mild abdominal pain and diarrhea in 14 cases (8.6%), and no patients discontinued the treatment. The BACs of patients with gastrointestinal adverse reactions were significantly lower than those without gastrointestinal adverse reactions (22.39 ± 10.38 vs. 37.89 ± 11.84, µ g/L, P<0.05). The BACs of patients with clinical effect were significantly higher than those failed to treatment (40.41 ± 11.69 vs. 23.84 ± 12.03, µ g/L, P<0.05). CONCLUSION: QHP was effective and safe in the treatment of patients with MDS and the effect was associated with BACs of patients.
Subject(s)
Arsenic/blood , Arsenicals/adverse effects , Arsenicals/therapeutic use , Drugs, Chinese Herbal/adverse effects , Drugs, Chinese Herbal/therapeutic use , Myelodysplastic Syndromes/blood , Myelodysplastic Syndromes/drug therapy , Blood Cell Count , Blood Transfusion , Humans , Karyotype , Powders , Risk FactorsABSTRACT
Cynodon dactylon is characterized by taxonomic and systematic complexity, and polyploidy is one of the factors responsible for its genetic and morphological diversity. The aim of the present study was to compare karyotypes of C. dactylon cytotypes based on fluorescent banding and nuclear DNA content. The nine C. dactylon accessions evaluated were obtained from the Active Germplasm Bank (BAG) of the United States Department of Agriculture (USDA). Roots were pretreated with cycloheximide, fixed in Carnoy's solution and subjected to enzymatic digestion. Slides were prepared by the dissociation and air-drying technique. The fluorescent banding pattern was obtained using chromomycin A3 (CMA)/4,6-dimidino-2-phenylindole (DAPI) staining and DNA content was estimated by flow cytometry. The chromosome number of the accessions ranged from 2n = 2x = 18 to 2n = 5x = 45. Chromosomal polymorphism was observed based on the distribution and number of heterochromatic bands, with CMA+ bands located in the pericentromeric position and DAPI+ bands mainly in the terminal position. PI477004-26 (2n = 3x = 27) and PI291966-27 (2n = 4x = 36) had the highest and lowest number of DAPI+ bands, respectively. The number of CMA+ bands was stable, as only PI477004-26, PI291966-27 and PI289750-10 (2n = 5x = 45) showed variation. There was no direct correlation between an increase in the ploidy level and an increase in the percentage of heterochromatic regions, mainly in relation to A-T-rich blocks. The chromosomal banding variation found reinforces the notion of allopolyploidy occurrence in C. dactylon and demonstrates the genomic complexity of this species regard to repetitive DNA content.
Subject(s)
Cynodon/classification , Cynodon/genetics , Karyotype , Chromosome Banding , Chromosomes, Plant , Karyotyping , PloidiesABSTRACT
The morphological, meiotic and chromosomal variability were studied in two cultivars of Calendula officinalis L. and their mutant lines obtained though chemical mutagenesis using diethyl sulphate (DES) (0.04%, 0.08%) and dimethyl sulphate (DMS) (0.025%, 0.05%). The studied cultivars displayed different sensitivity to DMS and DES mutagens. More M1 plants with morphological changes were observed in C. officinalis cv. 'Zolotoe more' than in cv. 'Rajskij sad'. DMS and DES at low concentrations had positive effects on main agro-metrical traits in both cultivars including plant height, inflorescence diameter and number of inflorescences per plant. Dose-dependent increase in number of various meiotic abnormalities was revealed in both mutant lines. Comparative karyotype analysis and FISH-based visualization of 45S and 5S rDNA indicated a high level of karyotype stability in M1 and M2 plants. Seed treatments with DMS and DES at certain concentrations resulted in higher yields of inflorescences in M1 plants compared to the control. In M2 generation, dose-dependent reduction in the yields of inflorescences was observed. Our findings demonstrate that DMS and DES at low concentrations have great potential in calendula mutation breeding.
Subject(s)
Calendula/cytology , Calendula/genetics , Mutagenesis/drug effects , Mutation , Phenotype , Calendula/drug effects , Cytogenetic Analysis , In Situ Hybridization, Fluorescence , Karyotype , Meiosis/geneticsABSTRACT
We present draft genome assemblies of Beta patula, a critically endangered wild beet endemic to the Madeira archipelago, and of the closely related Beta vulgaris ssp. maritima (sea beet). Evidence-based reference gene sets for B. patula and sea beet were generated, consisting of 25 127 and 27 662 genes, respectively. The genomes and gene sets of the two wild beets were compared with their cultivated sister taxon B. vulgaris ssp. vulgaris (sugar beet). Large syntenic regions were identified, and a display tool for automatic genome-wide synteny image generation was developed. Phylogenetic analysis based on 9861 genes showing 1:1:1 orthology supported the close relationship of B. patula to sea beet and sugar beet. A comparative analysis of the Rz2 locus, responsible for rhizomania resistance, suggested that the sequenced B. patula accession was rhizomania susceptible. Reference karyotypes for the two wild beets were established, and genomic rearrangements were detected. We consider our data as highly valuable and comprehensive resources for wild beet studies, B. patula conservation management, and sugar beet breeding research.
Subject(s)
Beta vulgaris/genetics , Genome, Plant , Plant Diseases/genetics , Beta vulgaris/virology , Chromosomes/genetics , Crops, Agricultural/genetics , Genetic Variation , Genomics , High-Throughput Nucleotide Sequencing , In Situ Hybridization, Fluorescence , Karyotype , Phylogeny , Plant Diseases/virology , Synteny/geneticsABSTRACT
Interspecific crossing is a promising approach for introgression of valuable traits to develop cultivars with improved characteristics. Allium fistulosum L. possesses numerous pest resistances that are lacking in the bulb onion (Allium cepa L.), including resistance to Stemphylium leaf blight (SLB). Advanced generations were produced by selfing and backcrossing to bulb onions of interspecific hybrids between A. cepa and A. fistulosum that showed resistance to SLB. Molecular classification of the cytoplasm established that all generations possessed normal (N) male-fertile cytoplasm of bulb onions. Genomic in situ hybridization (GISH) was used to study the chromosomal composition of the advanced generations and showed that most plants were allotetraploids possessing the complete diploid sets of both parental species. Because artificial doubling of chromosomes of the interspecific hybrids was not used, spontaneous polyploidization likely resulted from restitution gametes or somatic doubling. Recombinant chromosomes between A. cepa and A. fistulosum were identified, revealing that introgression of disease resistances to bulb onion should be possible.
Subject(s)
Chromosomes, Plant/genetics , Disease Resistance , In Situ Hybridization/methods , Onions/microbiology , Cytoplasm , Genetic Introgression , Genomics , Karyotype , Onions/genetics , Plant Breeding , Saccharomycetales/pathogenicity , TetraploidyABSTRACT
OBJECTIVES: To investigate the relationship between gene mutations and response to Compound Qinghuang Powder (, CQHP) in patients with myelodysplastic syndrome (MDS). METHODS: Forty-three MDS patients were genotyped by ultra-deep targeted sequencing and the clinical data of patients were collected and the relationship between them was analyzed. RESULTS: Up to 41.86% of patients harbored genet mutations, in most cases with more than one mutation. The most common mutations were in SF3B1, U2AF1, ASXL1, and DNMT3A. After treatment with CQHP, about 88.00% of patients no longer required blood transfusion, or needed half of prior transfusions. CONCLUSIONS: CQHP is an effective treatment for patients with MDS, especially those with gene mutations in SF3B1, DNMT3A, U2AF1, and/or ASXL1.
Subject(s)
Arsenic/therapeutic use , Arsenicals/therapeutic use , Drugs, Chinese Herbal/therapeutic use , Genetic Association Studies , Mutation/genetics , Myelodysplastic Syndromes/drug therapy , Myelodysplastic Syndromes/genetics , Adult , Blood Transfusion , Female , Humans , Karyotype , Male , Middle Aged , Treatment OutcomeABSTRACT
Understanding how cells acquire genetic mutations is a fundamental biological question with implications for many different areas of biomedical research, ranging from tumor evolution to drug resistance. While karyotypic heterogeneity is a hallmark of cancer cells, few mutations causing chromosome instability have been identified in cancer genomes, suggesting a nongenetic origin of this phenomenon. We found that in vitro exposure of karyotypically stable human colorectal cancer cell lines to environmental stress conditions triggered a wide variety of chromosomal changes and karyotypic heterogeneity. At the molecular level, hyperthermia induced polyploidization by perturbing centrosome function, preventing chromosome segregation, and attenuating the spindle assembly checkpoint. The combination of these effects resulted in mitotic exit without chromosome segregation. Finally, heat-induced tetraploid cells were on the average more resistant to chemotherapeutic agents. Our studies suggest that environmental perturbations promote karyotypic heterogeneity and could contribute to the emergence of drug resistance.
Subject(s)
Colorectal Neoplasms/genetics , Environment , Karyotype , Stress, Physiological , Cell Hypoxia , Cell Line, Tumor , Centrosome/metabolism , Chromosome Segregation , Chromosomes, Human/genetics , Culture Media, Serum-Free , Drug Resistance, Neoplasm , Humans , Hyperthermia, Induced , M Phase Cell Cycle Checkpoints , Metaphase , Mitosis , PolyploidyABSTRACT
This study used cytology, cytochemistry, and non-targeted metabolomics to investigate the distribution characteristic of polysaccharides, lipids, and all the metabolites present during five wheat (Triticum aestivum L.) anther developmental stages to provide insights into wheat anther development. Anthers were collected from the tetrad through trinucleate stages, and 1.5% (w/v) acetocarmine and 4',6-diamidino-2-phenylindole staining were used to confirm the developmental stage and visualize the nuclei, respectively. Polysaccharides and lipids were detected by staining with periodic acid-Schiff and Sudan Black B, respectively. The integrated optical density of the tapetum and microspores were calculated using IPP6.0 software. Furthermore, the metabolites were identified by gas chromatograph system coupled with a Pegasus HT time-of-flight mass spectrometer (GC-TOF-MS). The results indicated that the interior and exterior surface cells of anthers are orderly. Pollen was rich in numerous nutrient substances (e.g., lipids, insoluble carbohydrates, and others), and formed a normal sperm cell that contained three nuclei, i.e., one vegetative nuclei and two reproductive nuclei in the mature pollen. Semi-thin sectioning indicated that the tapetum cells degraded progressively from the tetrad to late uninucleate stage and disappeared from the bi-to trinucleate stages. Moreover, nutrient substances (lipids and insoluble carbohydrates) accumulated, were synthesized in the pollen, and gradually increased from the tetrad to trinucleate stages. Finally, the metabolomics results identified that 146 metabolites were present throughout the wheat anther developmental stages. Principal component analysis, hierarchical cluster analysis, and metabolite-metabolite correlation revealed distinct dynamic changes in metabolites. The metabolism of organic acids, amino acids, sugars, fatty acids, amines, polyols, and nucleotides were interrelated and involved in the tricarboxylic acid (TCA) cycle and glycolysis. Furthermore, their interactions were revealed using an integrated metabolic map, which indicated that the TCA cycle and glycolysis were very active during anther development to provide the required energy for anther and pollen development. Our study provides valuable insights into the mechanisms of substance metabolism in wheat anthers and can be used for possible application by metabolic engineers for the improvement of cell characteristics or creating new compounds and molecular breeders in improving pollen fertility or creating the ideal male sterile line, to improve wheat yield per unit area to address global food security.
Subject(s)
Metabolome , Pollen/growth & development , Pollen/metabolism , Triticum/metabolism , Triticum/physiology , Cluster Analysis , Karyotype , Lipids/analysis , Metabolic Networks and Pathways , Metabolomics , Pollen/cytology , Pollen/ultrastructure , Polysaccharides/analysis , Principal Component Analysis , Triticum/cytology , Triticum/ultrastructureABSTRACT
B chromosomes have been reported in about 15% of eukaryotes, but long-term dynamics of B chromosomes in a single natural population has rarely been analyzed. Prospero autumnale plants collected in 1981 and 1983 at Cuesta de La Palma population had shown the presence of B chromosomes. We analyze here seven additional samples collected between 1987 and 2015, and show that B frequency increased significantly during the 1980s and showed minor fluctuations between 2005 and 2015. A mother-offspring analysis of B chromosome transmission, at population level, showed significant drive on the male side (kB = 0.65) and significant drag on the female side (kB = 0.33), with average B transmission rate being very close to the Mendelian rate (0.5). No significant effects of B chromosomes were observed on a number of vigor and fertility-related traits. Within a parasite/host framework, these results suggest that B chromosomes' drive on the male side is the main pathway for B chromosome invasion, whereas B chromosome drag on the female side might be the main manifestation of host genome resistance in this species. Prospero autumnale thus illuminates a novel evolutionary pathway for B chromosome neutralization by means of a decrease in B transmission through the nondriving sex.