RESUMO
I-motifs (iMs) are four-stranded non-B DNA structures containing C-rich DNA sequences. The formation of iMs is sensitive to pH conditions and DNA methylation, although the extent of which is still unknown in both humans and plants. To investigate this, we here conducted iMab antibody-based immunoprecipitation and sequencing (iM-IP-seq) along with bisulfite sequencing using CK (original genomic DNA without methylation-related treatments) and hypermethylated or demethylated DNA at both pH 5.5 and 7.0 in rice, establishing a link between pH, DNA methylation and iM formation on a genome-wide scale. We found that iMs folded at pH 7.0 displayed higher methylation levels than those formed at pH 5.5. DNA demethylation and hypermethylation differently influenced iM formation at pH 7.0 and 5.5. Importantly, CG hypo-DMRs (differentially methylated regions) and CHH (H = A, C and T) hyper-DMRs alone or coordinated with CG/CHG hyper-DMRs may play determinant roles in the regulation of pH dependent iM formation. Thus, our study shows that the nature of DNA sequences alone or combined with their methylation status plays critical roles in determining pH-dependent formation of iMs. It therefore deepens the understanding of the pH and methylation dependent modulation of iM formation, which has important biological implications and practical applications.
Assuntos
Metilação de DNA , Oryza , Humanos , DNA/genética , Genoma , Concentração de Íons de Hidrogênio , Oryza/genéticaRESUMO
Single-stranded DNA (ssDNA) is essential for various DNA-templated processes in both eukaryotes and prokaryotes. However, comprehensive characterizations of ssDNA still lag in plants compared to nonplant systems. Here, we conducted in situ S1-sequencing, with starting gDNA ranging from 5 µg to 250 ng, followed by comprehensive characterizations of ssDNA in rice (Oryza sativa L.). We found that ssDNA loci were substantially associated with a subset of non-B DNA structures and functional genomic loci. Subtypes of ssDNA loci had distinct epigenetic features. Importantly, ssDNA may act alone or partly coordinate with non-B DNA structures, functional genomic loci, or epigenetic marks to actively or repressively modulate gene transcription, which is genomic region dependent and associated with the distinct accumulation of RNA Pol II. Moreover, distinct types of ssDNA had differential impacts on the activities and evolution of transposable elements (TEs) (especially common or conserved TEs) in the rice genome. Our study showcases an antibody-independent technique for characterizing non-B DNA structures or functional genomic loci in plants. It lays the groundwork and fills a crucial gap for further exploration of ssDNA, non-B DNA structures, or functional genomic loci, thereby advancing our understanding of their biology in plants.
Assuntos
DNA de Cadeia Simples , Genoma de Planta , Oryza , Oryza/genética , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , DNA de Plantas/genética , Elementos de DNA Transponíveis/genética , Epigênese GenéticaRESUMO
Seminal roots play a critical role in water and nutrient absorption, particularly in the early developmental stages of wheat. However, the genes responsible for controlling SRN in wheat remain largely unknown. Genetic mapping and functional analyses identified a candidate gene (TraesCS3D01G137200, TaSRN-3D) encoding a Ser/Thr kinase glycogen synthase kinase 3 (STKc_GSK3) that regulated SRN in wheat. Additionally, experiments involving hormone treatment, nitrate absorption and protein interaction were conducted to explore the regulatory mechanism of TaSRN-3D. Results showed that the TaSRN-3D4332 allele inhibited seminal roots initiation and development, while loss-of-function mutants showed significantly higher seminal root number (SRN). Exogenous application of epi-brassinolide could increase the SRN in a HS2-allelic background. Furthermore, chlorate sensitivity and 15N uptake assays revealed that a higher number of seminal roots promoted nitrate accumulation. TaBSR1 (BIN2-related SRN Regulator 1, orthologous to OsGRF4/GL2 in rice) acts as an interactor of TaSRN-3D and promotes TaBSR1 degradation to reduce SRN. This study provides valuable insights into understanding the genetic basis and regulatory network of SRN in wheat, highlighting their roles as potential targets for root-based improvement in wheat breeding.
Assuntos
Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Raízes de Plantas , Triticum , Alelos , Brassinosteroides/metabolismo , Mapeamento Cromossômico , Genes de Plantas , Quinase 3 da Glicogênio Sintase/metabolismo , Quinase 3 da Glicogênio Sintase/genética , Mutação/genética , Nitratos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Triticum/genética , Triticum/metabolismoRESUMO
COLD is a major naturally occurring stress that usually causes complex symptoms and severe yield loss in crops. R-loops function in various cellular processes, including development and stress responses, in plants. However, how R-loops function in COLD responses is largely unknown in COLD susceptible crops like rice (Oryza sativa L.). We conducted DRIP-Seq along with other omics data (RNA-Seq, DNase-Seq and ChIP-Seq) in rice with or without COLD treatment. COLD treatment caused R-loop reprogramming across the genome. COLD-biased R-loops had higher GC content and novel motifs for the binding of distinct transcription factors (TFs). Moreover, R-loops can directly/indirectly modulate the transcription of a subset of COLD-responsive genes, which can be mediated by R-loop overlapping TF-centered or cis-regulatory element-related regulatory networks and lncRNAs, accounting for c. 60% of COLD-induced expression of differential genes in rice, which is different from the findings in Arabidopsis. We validated two R-loop loci with contrasting (negative/positive) roles in the regulation of two individual COLD-responsive gene expression, as potential targets for enhanced COLD resistance. Our study provides detailed evidence showing functions of R-loop reprogramming during COLD responses and provides some potential R-loop loci for genetic and epigenetic manipulation toward breeding of rice varieties with enhanced COLD tolerance.
Assuntos
Arabidopsis , Oryza , Oryza/metabolismo , Estruturas R-Loop , Proteínas de Plantas/metabolismo , Melhoramento Vegetal , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Temperatura BaixaRESUMO
Pseudorabies (PR) is a highly infectious disease caused by pseudorabies virus (PRV). This study aimed to detect and identify recent outbreaks of genotype â ¡ PRV, and further analysis it's etiological characteristics and pathogenicity. The brain tissues with suspected PRV infection were isolated and the main virulence-related genes of the isolated PRV strain were amplified and sequenced for phylogenetic analysis. In addition, the pathogenicity of the isolated PRV strain to 6-week-old mice and 9-days-old suckling piglets were evaluated. The results showed that a PRV strain was successfully isolated and named PRV TJbd2023 strain, which could proliferate in PK-15 cells and TCID50 of the 6th generation virus reached 107.57/0.1ml. Phylogenetic trees and amino acids analysis were constructed based on full-length gE sequences, which showed that PRV TJbd2023 strain was clustered into genetype â ¡ PRV variant with a characteristic 21-nucleotide insertion (encoding 63AASTPAA69) in gC gene, and some amino acid point mutations were also found in other virulence- related genes, including gB protein R223H and E836K, gD protein R320S, and gE protein T242A. Animal experiments showed that TJbd2023 could cause acute neurological symptoms with 103.41/mL LD50 on KM mice, and intranasal inoculation of suckling piglets with 2 ml of TJbd2023 strain(106.57/0.1ml) led to a mortality rate of 66.70%. Emerging genotype â ¡ PRV variant such as isolated in our research named TJbd2023 with high pathogenicity might be responsible for recent outbreaks of PRV and immunization failure of Bartha-K61 vaccine in Tianjin, China.
RESUMO
I-motifs (iMs) are non-canonical DNA secondary structures that fold from cytosine (C)-rich genomic DNA regions termed putative i-motif forming sequences (PiMFSs). The structure of iMs is stabilized by hemiprotonated C-C base pairs, and their functions are now suspected in key cellular processes in human cells such as genome stability and regulation of gene transcription. In plants, their biological relevance is still largely unknown. Here, we characterized PiMFSs with high potential for i-motif formation in the rice genome by developing and applying a protocol hinging on an iMab antibody-based immunoprecipitation (IP) coupled with high-throughput sequencing (seq), consequently termed iM-IP-seq. We found that PiMFSs had intrinsic subgenomic distributions, cis-regulatory functions and an intricate relationship with DNA methylation. We indeed found that the coordination of PiMFSs with DNA methylation may affect dynamics of transposable elements (TEs) among different cultivated Oryza subpopulations or during evolution of wild rice species. Collectively, our study provides first and unique insights into the biology of iMs in plants, with potential applications in plant biotechnology for improving important agronomic rice traits.
Assuntos
Elementos de DNA Transponíveis , Oryza , Citosina , Metilação de DNA , Elementos de DNA Transponíveis/genética , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Oryza/genéticaRESUMO
Eukaryotic gene transcription is fine-tuned by precise spatiotemporal interactions between cis-regulatory elements (CREs) and trans-acting factors. However, how CREs individually or coordinated with epigenetic marks function in regulating homoeolog bias expression is still largely unknown in wheat. In this study, through comprehensively characterizing open chromatin coupled with DNA methylation in the seedling and spikelet of common wheat, we observed that differential chromatin openness occurred between the seedling and spikelet, which plays important roles in tissue development through regulating the expression of related genes or through the transcription factor (TF)-centered regulatory network. Moreover, we found that CHH methylation may act as a key determinant affecting the differential binding of TFs, thereby resulting in differential expression of target genes. In addition, we found that sequence variations in MNase hypersensitive sites (MHSs) result in the differential expression of key genes responsible for important agronomic traits. Thus, our study provides new insights into the roles of CREs in regulating tissue or homoeolog bias expression, and controlling important agronomic traits in common wheat. It also provides potential CREs for genetic and epigenetic manipulation toward improving desirable traits for wheat molecule breeding.
Assuntos
Cromatina , Metilação de DNA , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição , Triticum , Triticum/genética , Triticum/metabolismo , Cromatina/metabolismo , Cromatina/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Epigênese Genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plântula/genética , Plântula/metabolismo , Plântula/crescimento & desenvolvimento , Redes Reguladoras de GenesRESUMO
A DNA G-quadruplex (G4) is a non-canonical four-stranded nucleic acid structure involved in many biological processes in mammals. The current knowledge on plant DNA G4s, however, is limited; whether and how DNA G4s impact gene expression in plants is still largely unknown. Here, we applied a protocol referred to as BG4-DNA-IP-seq followed by a comprehensive characterization of DNA G4s in rice (Oryza sativa L.); we next integrated dG4s (experimentally detectable G4s) with existing omics data and found that dG4s exhibited differential DNA methylation between transposable element (TE) and non-TE genes. dG4 regions displayed genic-dependent enrichment of epigenomic signatures; finally, we showed that these sites displayed a positive association with expression of DNA G4-containing genes when located at promoters, and a negative association when located in the gene body, suggesting localization-dependent promotional/repressive roles of DNA G4s in regulating gene transcription. This study reveals interrelations between DNA G4s and epigenomic signatures, as well as implicates DNA G4s in modulating gene transcription in rice. Our study provides valuable resources for the functional characterization or bioengineering of some of key DNA G4s in rice.
Assuntos
Produtos Agrícolas/genética , DNA , Quadruplex G , Oryza/genética , Plantas Geneticamente Modificadas/genética , Transcrição Gênica , Epigenômica , Regulação da Expressão Gênica de Plantas , Genes de PlantasRESUMO
Six subspecies of hexaploid wheat (Triticum aestivum) have been identified, but the origin of Indian dwarf wheat (Triticum sphaerococcum), the only subspecies with round grains, is currently unknown. Here, we isolated the grain-shape gene Tasg-D1 in T sphaerococcum via positional cloning. Tasg-D1 encodes a Ser/Thr protein kinase glycogen synthase kinase3 (STKc_GSK3) that negatively regulates brassinosteroid signaling. Expression of TaSG-D1 and the mutant form Tasg-D1 in Arabidopsis (Arabidopsis thaliana) suggested that a single amino acid substitution in the Thr-283-Arg-284-Glu-285-Glu-286 domain of TaSG-D1 enhances protein stability in response to brassinosteroids, likely leading to formation of round grains in wheat. This gain-of-function mutation has pleiotropic effects on plant architecture and exhibits incomplete dominance. Haplotype analysis of 898 wheat accessions indicated that the origin of T sphaerococcum in ancient India involved at least two independent mutations of TaSG-D1 Our results demonstrate that modest genetic changes in a single gene can induce dramatic phenotypic changes.
Assuntos
Substituição de Aminoácidos/genética , Quinase 3 da Glicogênio Sintase/genética , Sementes/anatomia & histologia , Triticum/anatomia & histologia , Triticum/genética , Sequência de Bases , Brassinosteroides/metabolismo , Clonagem Molecular , Haplótipos/genética , Fenótipo , Mutação Puntual/genética , Transdução de Sinais , Triticum/crescimento & desenvolvimentoRESUMO
With the implementation of China's one-child policy and the increasing living costs, a large number of young people are expected to postpone reaching adulthood. However, little research has explored the patterns of Chinese young people's transition to adulthood. Using a person-centred approach, the current study examined the commonly accepted markers of adulthood status endorsed and attained by 1203 Chinese emerging adults aged 18-29 years. We further compared the distinct adulthood statuses with regard to perceptions of stress and well-being. Latent profile analysis identified four adulthood status profiles: diffused (16.0%), moratorium (45.3%), transitional (23.3%) and achieved (15.4%). Females, those who had no job or came from low family socioeconomics, were more likely to be in the moratorium status. Compared to the other two profiles, participants in diffused and moratorium profiles reported higher levels of perceived stress and lower well-being. These results suggest that there are distinct profiles of Chinese emerging adults on the transition path to adulthood, with a large proportion of them not yet reaching adulthood, and that different statuses of adulthood may be associated with different psychological outcomes.
Assuntos
Bem-Estar Psicológico , Estresse Psicológico , Adolescente , Adulto , Feminino , Humanos , População do Leste Asiático , Fatores Socioeconômicos , Adulto Jovem , Masculino , Fatores EtáriosRESUMO
BACKGROUND: Cold is one of the main abiotic stresses that severely affect plant growth and development, and crop productivity as well. Transcriptional changes during cold stress have already been intensively studied in various plant species. However, the gene networks involved in the regulation of differential cold tolerance between tobacco varieties with contrasting cold resistance are quite limited. RESULTS: Here, we conducted multiple time-point transcriptomic analyses using Tai tobacco (TT, cold susceptibility) and Yan tobacco (YT, cold resistance) with contrasting cold responses. We identified similar DEGs in both cultivars after comparing with the corresponding control (without cold treatment), which were mainly involved in response to abiotic stimuli, metabolic processes, kinase activities. Through comparison of the two cultivars at each time point, in contrast to TT, YT had higher expression levels of the genes responsible for environmental stresses. By applying Weighted Gene Co-Expression Network Analysis (WGCNA), we identified two main modules: the pink module was similar while the brown module was distinct between the two cultivars. Moreover, we obtained 100 hub genes, including 11 important transcription factors (TFs) potentially involved in cold stress, 3 key TFs in the brown module and 8 key TFs in the pink module. More importantly, according to the genetic regulatory networks (GRNs) between TFs and other genes or TFs by using GENIE3, we identified 3 TFs (ABI3/VP1, ARR-B and WRKY) mainly functioning in differential cold responses between two cultivars, and 3 key TFs (GRAS, AP2-EREBP and C2H2) primarily involved in cold responses. CONCLUSION: Collectively, our study provides valuable resources for transcriptome- based gene network studies of cold responses in tobacco. It helps to reveal how key cold responsive TFs or other genes are regulated through network. It also helps to identify the potential key cold responsive genes for the genetic manipulation of tobacco cultivars with enhanced cold tolerance in the future.
Assuntos
Redes Reguladoras de Genes , Nicotiana , Resposta ao Choque Frio/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Nicotiana/genética , TranscriptomaRESUMO
The spikelet number and heading date are two crucial and correlated traits for yield in wheat. Here, a quantitative trait locus (QTL) analysis was conducted in F8 recombinant inbred lines (RILs) derived from crossing two common wheats with different spikelet numbers. A total of 15 stable QTL influencing total spikelet number (TSN) and heading date (HD) were detected. Notably, FT-D1, a well-known flowering time gene in wheat, was located within the finely mapped interval of a major QTL on 7DS (QTsn/Hd.cau-7D). A causal indel of one G in the third exon of FT-D1 was significantly associated with total spikelet number and heading date. Consistently, CRISPR/Cas9 mutant lines with homozygous mutations in FT-D1 displayed an increase in total spikelet number and heading date when compared with wild type. Moreover, one simple and robust marker developed according to the polymorphic site of FT-D1 revealed that this one G indel had been preferentially selected to adapt to different environments. Collectively, these data provide further insights into the genetic basis of spikelet number and heading date, and the diagnostic marker of FT-D1 will be useful for marker-assisted pyramiding in wheat breeding.
Assuntos
Melhoramento Vegetal , Triticum , Éxons/genética , Nucleotídeos , Locos de Características Quantitativas/genética , Triticum/genéticaRESUMO
DNA G-quadruplexes (G4s) are non-canonical four-stranded DNA structures involved in various biological processes in eukaryotes. Molecularly crowded solutions and monovalent cations have been reported to stabilize in vitro and in vivo G4 formation. However, how K+ and Na+ affect G4 formation genome-wide is still unclear in plants. Here, we conducted BG4-DNA-IP-seq, DNA immunoprecipitation with anti-BG4 antibody coupled with sequencing, under K+ and Na+ + PEG conditions in vitro. We found that K+-specific IP-G4s had a longer peak size, more GC and PQS content, and distinct AT and GC skews compared to Na+-specific IP-G4s. Moreover, K+- and Na+-specific IP-G4s exhibited differential subgenomic enrichment and distinct putative functional motifs for the binding of certain trans-factors. More importantly, we found that K+-specific IP-G4s were more associated with active marks, such as active histone marks, and low DNA methylation levels, as compared to Na+-specific IP-G4s; thus, K+-specific IP-G4s in combination with active chromatin features facilitate the expression of overlapping genes. In addition, K+- and Na+-specific IP-G4 overlapping genes exhibited differential GO (gene ontology) terms, suggesting they may have distinct biological relevance in rice. Thus, our study, for the first time, explores the effects of K+ and Na+ on global G4 formation in vitro, thereby providing valuable resources for functional G4 studies in rice. It will provide certain G4 loci for the biotechnological engineering of rice in the future.
Assuntos
Quadruplex G , Oryza , DNA/química , Epigenômica , Código das Histonas , Oryza/genéticaRESUMO
KEY MESSAGE: Thirty environmentally stable QTL controlling grain size and/or plant height were identified, among which QTgw.cau-7D was delimited into the physical interval of approximately 4.4 Mb. Grain size and plant height (PHT) are important agronomic traits in wheat breeding. To dissect the genetic basis of these traits, we conducted a quantitative trait locus (QTL) analysis using recombinant inbred lines (RILs). In total, 30 environmentally stable QTL for thousand grain weight (TGW), grain length (GL), grain width (GW) and PHT were detected. Notably, one major pleiotropic QTL on chromosome arm 3DS explained the highest phenotypic variance for TGW, GL and PHT, and two stable QTL (QGw.cau-4B and QGw.cau-7D) on chromosome arms 4BS and 7DS contributed greater effects for GW. Furthermore, the stable QTL controlling grain size (QTgw.cau-7D and QGw.cau-7D) were delimited into the physical interval of approximately 4.4 Mb harboring 56 annotated genes. The elite NILs of QTgw.cau-7D increased TGW by 12.79-21.75% and GW by 4.10-8.47% across all three environments. Collectively, these results provide further insight into the genetic basis of TGW, GL, GW and PHT, and the fine-mapped QTgw.cau-7D will be an attractive target for positional cloning and marker-assisted selection in wheat breeding programs.
Assuntos
Mapeamento Físico do Cromossomo , Locos de Características Quantitativas/genética , Sementes/anatomia & histologia , Sementes/genética , Triticum/anatomia & histologia , Triticum/genética , Ligação Genética , Endogamia , Tamanho do Órgão , FenótipoRESUMO
KEY MESSAGE: Three pleiotropic QTL regions associated with spikelet number and heading date were identified, with FT-A1 considered the candidate gene for QTspn/Hd.cau-7A. Spikelet number traits and heading date (HD) play key roles in yield improvement of wheat and its wide adaptation to different environments. Here, we used a Recombinant Inbred Lines population derived from a cross between Yi5029 (5029) and Nongda4332 (4332) to construct a high-density genetic linkage map and identify quantitative trait loci (QTL) associated with total spikelet number per spike (TSPN), fertile spikelet number per spike (FSPN), sterile spikelet number per spike (SSPN) and HD. A total of 22 environmentally stable QTL for TSPN, FSPN, SSPN and HD were identified. Notably, three pleiotropic QTL regions for TSPN and HD were detected on chromosomes 2A, 7A and 7D. The QTL associated with TSPN and HD on chromosome 7AS was designated QTspn/Hd.cau-7A. Furthermore, the candidate gene FT-A1 located in the region of QTspn/Hd.cau-7A had a single-nucleotide polymorphism (T-G) within the third exon, which might be the cause of diversity in spikelet number and HD between the two parents. Additionally, we developed a semi-thermal asymmetric reverse PCR (STARP) marker to analyze the geographical distribution and evolution of FT-A1 (T or G) alleles. This study contributes to our understanding of the molecular mechanisms of the four traits (TSPN, FSPN, SSPN and HD) and provides further insights into the genetic relationship between spikelet number traits and HD in wheat.
Assuntos
Cromossomos de Plantas , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Triticum/crescimento & desenvolvimento , Triticum/genética , Alelos , Mapeamento Cromossômico , Genes de Plantas , Ligação Genética , Haplótipos , Fenótipo , Característica Quantitativa HerdávelRESUMO
This cross-cultural study of Finnish and Chinese students set out to compare the levels of achievement motivation (AM) in order to investigate whether the differences in them might be explained by the different cultural response styles and whether these response styles could be controlled for with a method which includes response style variables as covariates in ANCOVA. This study also scrutinizes relationships between perceived teaching-learning environments (TLE) and AM within each cultural group. The survey sample consisted of 3,035 Finnish and 2,309 mainland Chinese university students. Finnish students were found to rate the level of AM markedly higher than do Chinese students. It was determined that the method applied for response style controlling is not suitable for cross-cultural studies, even though it is recommended for this use. A modification of the method, which is based on robust statistical tools, was found not to change this conclusion, but it can nevertheless be used to obtain useful information about the effects of response style differences. The results also show that similar relationships between AM and TLE could be identified in the data of both groups. However, for the Finnish group AM is related to perceived suitable workload, whereas for the Chinese group it is related to teacher encouragement.
Assuntos
Sucesso Acadêmico , Comparação Transcultural , Motivação , Estudantes/psicologia , China , Feminino , Finlândia , Humanos , Masculino , Meio Social , Inquéritos e Questionários , Universidades , Carga de TrabalhoRESUMO
KEY MESSAGE: Two QTL with pleiotropic effects on plant height and spike length linked in coupling phase on chromosome 2DS were dissected, and diagnostic marker for each QTL was developed. Plant height (PHT) is a crucial trait related to plant architecture and yield potential, and dissection of its underlying genetic basis would help to improve the efficiency of designed breeding in wheat. Here, two quantitative trait loci (QTL) linked in coupling phase on the short arm of chromosome 2D with pleiotropic effects on PHT and spike length, QPht/Sl.cau-2D.1 and QPht/Sl.cau-2D.2, were separated and characterized. QPht/Sl.cau-2D.1 is a novel QTL located between SNP makers BS00022234_51 and BobWhite_rep_c63957_1472. QPht/Sl.cau-2D.2 is mapped between two SSR markers, SSR-2062 and Xgwm484, which are located on the same genomic interval as Rht8. Moreover, the diagnostic marker tightly linked with each QTL was developed for the haplotype analysis using diverse panels of wheat accessions. The frequency of the height-reduced allele of QPht/Sl.cau-2D.1 is much lower than that of QPht/Sl.cau-2D.2, suggesting that this novel QTL may be an attractive target for genetic improvement. Consistent with a previous study of Rht8, a significant difference in cell length was observed between the NILs of QPht/Sl.cau-2D.2. By contrast, there was no difference in cell length between NILs of QPht/Sl.cau-2D.1, indicating that the underlying molecular mechanism for these two QTL may be different. Collectively, these data provide a new example of QTL dissection, and the developed diagnostic markers will be useful in marker-assisted pyramiding of QPht/Sl.cau-2D.1 and/or QPht/Sl.cau-2D.2 with the other genes in wheat breeding.
Assuntos
Cromossomos de Plantas/genética , Marcadores Genéticos , Melhoramento Vegetal , Proteínas de Plantas/genética , Locos de Características Quantitativas , Sementes/genética , Triticum/genética , Mapeamento Cromossômico/métodos , Ligação Genética , Haplótipos , Repetições de Microssatélites , Fenótipo , Proteínas de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimentoRESUMO
Theoretical and Applied Genetics.
RESUMO
KEY MESSAGE: Two QTL with pleiotropic effects on plant height and spike length linked in coupling phase on chromosome 2DS were dissected, and diagnostic marker for each QTL was developed. Plant height (PHT) is a crucial trait related to plant architecture and yield potential, and dissection of its underlying genetic basis would help to improve the efficiency of designed breeding in wheat. Here, two quantitative trait loci (QTL) linked in coupling phase on the short arm of chromosome 2D with pleiotropic effects on PHT and spike length, QPht/Sl.cau-2D.1 and QPht/Sl.cau-2D.2, were separated and characterized. QPht/Sl.cau-2D.1 is a novel QTL located between SNP makers BS00022234_51 and BobWhite_rep_c63957_1472. QPht/Sl.cau-2D.2 is mapped between two SSR markers, SSR-2062 and Xgwm484, which are located on the same genomic interval as Rht8. Moreover, the diagnostic marker tightly linked with each QTL was developed for the haplotype analysis using diverse panels of wheat accessions. The frequency of the height-reduced allele of QPht/Sl.cau-2D.1 is much lower than that of QPht/Sl.cau-2D.2, suggesting that this novel QTL may be an attractive target for genetic improvement. Consistent with a previous study of Rht8, a significant difference in cell length was observed between the NILs of QPht/Sl.cau-2D.2. By contrast, there was no difference in cell length between NILs of QPht/Sl.cau-2D.1, indicating that the underlying molecular mechanism for these two QTL may be different. Collectively, these data provide a new example of QTL dissection, and the developed diagnostic markers will be useful in marker-assisted pyramiding of QPht/Sl.cau-2D.1 and/or QPht/Sl.cau-2D.2 with the other genes in wheat breeding.
Assuntos
Locos de Características Quantitativas , Triticum/crescimento & desenvolvimento , Triticum/genética , Mapeamento Cromossômico , Genes de Plantas , Marcadores Genéticos , Haplótipos , Repetições de Microssatélites , Fenótipo , Melhoramento VegetalRESUMO
In this study the levels of experienced burnout of Finnish and Chinese university students are compared using School Burnout Inventory (SBI). This study is motivated by earlier studies, which suggest that the level of student burnout is different in the culturally distinct Finnish and Chinese university systems, but which are based on different research instruments for the two groups. The sample studied consisted of 3,035 Finnish students and 2,309 Chinese students. Because of the cross-cultural nature of this study the level of structural equivalence of SBI between the cultural groups was examined and the effect of different response styles on the results was taken into account. Both standard and robust statistical methods were used for the analyses. The results showed that SBI with two extracted components is suitable for cross-cultural analysis between Finnish and Chinese university students. Virtually no difference was found in experienced overall burnout between the Finnish and Chinese students, which means that both university systems contain factors causing similar levels of student burnout. This study also verified that controlling for the response styles is important in cross-cultural studies as it was found to have a distinct effect on the results obtained from mean-level comparisons.