Recently, engineered minichromosomes have been produced using a telomere-mediated truncation technique in some plants. However, the study on transferring genes to minichromosomes is very limited.Here, telomere-mediate...Recently, engineered minichromosomes have been produced using a telomere-mediated truncation technique in some plants. However, the study on transferring genes to minichromosomes is very limited.Here, telomere-mediated truncation was successfully performed in common wheat（Triticum aestivum）to generate stable truncated chromosomes accompanied by a relatively high frequency of chromosomal rearrangements. After the cross between transgenic parents, a promoter-less DsRed gene in a chromosome from one parent was transferred to another chromosome from the other parent at the site behind a maize ubiquitin promoter via the Cre/lox system. DsRed transcripts and red fluorescent proteins were detected in the recombinant plants. In one such seedling, transgenic signals were detected at the centric terminus of chromosome 4D and the distal terminus of chromosome 3A. Clear translocations could be detected at the transgenic loci of these two chromosomes. Intriguingly, signals of centric-specific sequences were co-localized with the translocated D-group chromosomal segment in the terminal region of chromosome 3A. Our results indicate that the Cre/lox system induces the gene swapping to the target chromosome and non-homologous chromosomal recombination simultaneously. These approaches could offer a platform to transfer large DNA fragments or even terminal chromosomal segments to other chromosomes of the natural genome.展开更多
The Triticum-Aegilops complex groups demonstrated high cross-affinity with each other to overcome the barriers of distant hybridization(Loureiro et al.,2023).Distant hybridization involves two distinct yet closely rel...The Triticum-Aegilops complex groups demonstrated high cross-affinity with each other to overcome the barriers of distant hybridization(Loureiro et al.,2023).Distant hybridization involves two distinct yet closely related events:hybridization and genome doubling.Previous studies have indicated that bursts of transposable elements(TEs)can occur as a consequence or concomitant to hybridization or genome duplication(Parisod et al.,2010).This raises an important scientific question regarding how the TEs-rich centromere region copes with genomic shock(McClintock,1984).The Triticum-Aegilops species complexes,particularly in the F1,So,and subsequent early generations resulting from successive selfcrossing,offer an opportunity to investigate whether the centromere environment undergoes reconstruction and the associated mechanisms that maintain genomic stability.展开更多
Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated o...Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated over 400 fully resolved centromeres from 17 diploid angiosperms spanning 180 million years of divergence,along with 1,000+pan-genomic assemblies,resequencing datasets,and congeneric wholegenome sequences.We showed that angiosperm centromere organization is determined by lineagespecific combinations of satellite repeats and transposable elements(TEs),which,in turn,shape distinct epigenetic landscapes and evolutionary trajectories within centromeres.In particular,TE insertion patterns were found to be key drivers of structural diversification and positional shift of centromeres in angiosperms.Intriguingly,population-level analyses revealed considerable plasticity in centromere sequences across species,with satellite repeats serving as focal points of evolutionary change and exhibiting species-specific heterogeneity patterns.Temporal reconstructions across congeneric species revealed the emergence and subsequent differentiation of centromeric repeats,outlining a dynamic continuum from gradual sequence diversification to complete turnover during speciation,often accompanied by karyotype reorganization.By integrating intra-and inter-species comparisons,we propose a unifying framework in which centromere innovation is governed by a delicate interplay between genome evolution,chromosomal shuffling,and selection constraints,resulting in phylogenomic signatures of centromeredriven speciation.展开更多
Spike architecture influences both grain weight and grain number per spike,which are the two major components of grain yield in bread wheat(Triticum aestivum L.).However,the complex wheat genome and the influence of var...Spike architecture influences both grain weight and grain number per spike,which are the two major components of grain yield in bread wheat(Triticum aestivum L.).However,the complex wheat genome and the influence of various environmental factors pose challenges in mapping the causal genes that affect spike traits.Here,we systematically identified genes involved in spike trait formation by integrating information on genomic variation and gene regulatory networks controlling young spike development in wheat.We identified 170 loci that are responsible for variations in spike length,spikelet number per spike,and grain number per spike through genome-wide association study and meta-QTL analyses.We constructed gene regulatory networks for young inflorescences at the double ridge stage and thefloret primordium stage,in which the spikelet meristem and thefloret meristem are predominant,respec-tively,by integrating transcriptome,histone modification,chromatin accessibility,eQTL,and protein–pro-tein interactome data.From these networks,we identified 169 hub genes located in 76 of the 170 QTL regions whose polymorphisms are significantly associated with variation in spike traits.The functions of TaZF-B1,VRT-B2,and TaSPL15-A/D in establishment of wheat spike architecture were verified.This study provides valuable molecular resources for understanding spike traits and demonstrates that combining genetic analysis and developmental regulatory networks is a robust approach for dissection of complex traits.展开更多
The widely recognized pleiotropic adult plant resistance gene Lr34 encodes an ATP-binding cassette transporter and plays an important role in breeding wheat for enhanced resistance to multiple fungal diseases. Despite...The widely recognized pleiotropic adult plant resistance gene Lr34 encodes an ATP-binding cassette transporter and plays an important role in breeding wheat for enhanced resistance to multiple fungal diseases. Despite its significance, the mechanisms underlying Lr34-mediated pathogen defense remain largely unknown. Our study demonstrates that wheat lines carrying the Lr34res allele exhibit thicker cell walls and enhanced resistance to fungal penetration compared to those without Lr34res. Transcriptome and metabolite profiling revealed that the lignin biosynthetic pathway is suppressed in lr34 mutants, indicating a disruption in cell wall lignification. Additionally, we discovered that lr34 mutant lines are hypersensitive to sinapyl alcohol, a major monolignol crucial for cell wall lignification. Yeast accumulation and efflux assays confirmed that the LR34 protein functions as a sinapyl alcohol transporter. Both genetic and virus-induced gene silencing experiments demonstrated that the disease resistance conferred by Lr34 can be enhanced by incorporating the TaCOMT-3B gene, which is responsible for the biosynthesis of sinapyl alcohol. Collectively, our findings provide novel insights into the role of Lr34 in disease resistance through mediating sinapyl alcohol transport and cell wall deposition, and highlight the synergistic effect of TaCOMT-3B and Lr34 against multiple fungal pathogens by mediating cell wall lignification in adult wheat plants.展开更多
基金supported by the National Key Research and Development Program of China(2016YFD0102003)the Ministry of Science and Technology(MOST)Project(2016ZX08010002 and 2014ZX0801006B)
文摘Recently, engineered minichromosomes have been produced using a telomere-mediated truncation technique in some plants. However, the study on transferring genes to minichromosomes is very limited.Here, telomere-mediated truncation was successfully performed in common wheat（Triticum aestivum）to generate stable truncated chromosomes accompanied by a relatively high frequency of chromosomal rearrangements. After the cross between transgenic parents, a promoter-less DsRed gene in a chromosome from one parent was transferred to another chromosome from the other parent at the site behind a maize ubiquitin promoter via the Cre/lox system. DsRed transcripts and red fluorescent proteins were detected in the recombinant plants. In one such seedling, transgenic signals were detected at the centric terminus of chromosome 4D and the distal terminus of chromosome 3A. Clear translocations could be detected at the transgenic loci of these two chromosomes. Intriguingly, signals of centric-specific sequences were co-localized with the translocated D-group chromosomal segment in the terminal region of chromosome 3A. Our results indicate that the Cre/lox system induces the gene swapping to the target chromosome and non-homologous chromosomal recombination simultaneously. These approaches could offer a platform to transfer large DNA fragments or even terminal chromosomal segments to other chromosomes of the natural genome.
基金the National Natural Science Foundation of China(31991212)the National Key Research and Development Program of China(2022YFF1003303).
文摘The Triticum-Aegilops complex groups demonstrated high cross-affinity with each other to overcome the barriers of distant hybridization(Loureiro et al.,2023).Distant hybridization involves two distinct yet closely related events:hybridization and genome doubling.Previous studies have indicated that bursts of transposable elements(TEs)can occur as a consequence or concomitant to hybridization or genome duplication(Parisod et al.,2010).This raises an important scientific question regarding how the TEs-rich centromere region copes with genomic shock(McClintock,1984).The Triticum-Aegilops species complexes,particularly in the F1,So,and subsequent early generations resulting from successive selfcrossing,offer an opportunity to investigate whether the centromere environment undergoes reconstruction and the associated mechanisms that maintain genomic stability.
基金supported by the National Natural Science Foundation of China(32170571 and 32400451)Hubei Provincial Technological Innovation Plan Project(2025BBB014)+2 种基金the project TowArdsNextGENeration Crops(no.CZ.02.01.01/00/22_008/0004581)of the ERDF Programme Johannes Amos ComeniusProject 2662024JC010 was supported by the Fundamental Research Funds for the Central UniversitiesAdditional funding was provided by the Young Top-notch Talent Cultivation Program of Hubei Province and the Natural Science Foundation of Hubei Province of China(2024AFB116).
文摘Centromeres are indispensable for accurate chromosome segregation,but are subject to rapid sequence turnover while maintaining conserved functions--a paradox in genome evolution.To unravel this paradox,we integrated over 400 fully resolved centromeres from 17 diploid angiosperms spanning 180 million years of divergence,along with 1,000+pan-genomic assemblies,resequencing datasets,and congeneric wholegenome sequences.We showed that angiosperm centromere organization is determined by lineagespecific combinations of satellite repeats and transposable elements(TEs),which,in turn,shape distinct epigenetic landscapes and evolutionary trajectories within centromeres.In particular,TE insertion patterns were found to be key drivers of structural diversification and positional shift of centromeres in angiosperms.Intriguingly,population-level analyses revealed considerable plasticity in centromere sequences across species,with satellite repeats serving as focal points of evolutionary change and exhibiting species-specific heterogeneity patterns.Temporal reconstructions across congeneric species revealed the emergence and subsequent differentiation of centromeric repeats,outlining a dynamic continuum from gradual sequence diversification to complete turnover during speciation,often accompanied by karyotype reorganization.By integrating intra-and inter-species comparisons,we propose a unifying framework in which centromere innovation is governed by a delicate interplay between genome evolution,chromosomal shuffling,and selection constraints,resulting in phylogenomic signatures of centromeredriven speciation.
基金supported by STI2030-Major Projects (2023ZD0406802)the Fundamental Research Funds for the Central Universities (2662020ZKPY002)+1 种基金the National Key Laboratory of Crop Genetic Improvement Self-Research Program (ZW19A0201)the HZAUAGIS Cooperation Fund 869 (SZYJY2021006).
文摘Spike architecture influences both grain weight and grain number per spike,which are the two major components of grain yield in bread wheat(Triticum aestivum L.).However,the complex wheat genome and the influence of various environmental factors pose challenges in mapping the causal genes that affect spike traits.Here,we systematically identified genes involved in spike trait formation by integrating information on genomic variation and gene regulatory networks controlling young spike development in wheat.We identified 170 loci that are responsible for variations in spike length,spikelet number per spike,and grain number per spike through genome-wide association study and meta-QTL analyses.We constructed gene regulatory networks for young inflorescences at the double ridge stage and thefloret primordium stage,in which the spikelet meristem and thefloret meristem are predominant,respec-tively,by integrating transcriptome,histone modification,chromatin accessibility,eQTL,and protein–pro-tein interactome data.From these networks,we identified 169 hub genes located in 76 of the 170 QTL regions whose polymorphisms are significantly associated with variation in spike traits.The functions of TaZF-B1,VRT-B2,and TaSPL15-A/D in establishment of wheat spike architecture were verified.This study provides valuable molecular resources for understanding spike traits and demonstrates that combining genetic analysis and developmental regulatory networks is a robust approach for dissection of complex traits.
基金National Natural Science Foundation of China(grant nos.31861143010 and 32372173)National Key Research and Development Program of China(grants 2022YFD1201300 and 2022YFD1201500)+1 种基金Fundamental Research Funds for the Central Universities(2662020ZKPY005)Hubei Hongshan Laboratory(2022hspy001,2021hskf008,and 2022hspy010).
文摘The widely recognized pleiotropic adult plant resistance gene Lr34 encodes an ATP-binding cassette transporter and plays an important role in breeding wheat for enhanced resistance to multiple fungal diseases. Despite its significance, the mechanisms underlying Lr34-mediated pathogen defense remain largely unknown. Our study demonstrates that wheat lines carrying the Lr34res allele exhibit thicker cell walls and enhanced resistance to fungal penetration compared to those without Lr34res. Transcriptome and metabolite profiling revealed that the lignin biosynthetic pathway is suppressed in lr34 mutants, indicating a disruption in cell wall lignification. Additionally, we discovered that lr34 mutant lines are hypersensitive to sinapyl alcohol, a major monolignol crucial for cell wall lignification. Yeast accumulation and efflux assays confirmed that the LR34 protein functions as a sinapyl alcohol transporter. Both genetic and virus-induced gene silencing experiments demonstrated that the disease resistance conferred by Lr34 can be enhanced by incorporating the TaCOMT-3B gene, which is responsible for the biosynthesis of sinapyl alcohol. Collectively, our findings provide novel insights into the role of Lr34 in disease resistance through mediating sinapyl alcohol transport and cell wall deposition, and highlight the synergistic effect of TaCOMT-3B and Lr34 against multiple fungal pathogens by mediating cell wall lignification in adult wheat plants.
