Pyrus pyrifolia,commonly known as sand pear,is a key economic fruit tree in temperate regions that possesses highly diverse germplasm resources for pear quality improvement.However,research on the relationship between...Pyrus pyrifolia,commonly known as sand pear,is a key economic fruit tree in temperate regions that possesses highly diverse germplasm resources for pear quality improvement.However,research on the relationship between resistance and fruit quality traits in the breeding of fruit species like pear is limited.Pan-transcriptomes effectively capture genetic information from coding regions and reflect variations in gene expression between individuals.Here,we constructed a pan-transcriptome based on 506 samples from different tissues of sand pear,and explored the intrinsic relationships among phenotypes and the selection for disease resistance during improvement based on expression presence/absence variations(eP AVs).The pan-transcriptome in this study contains 156,744 transcripts,among which the novel transcripts showed significant enrichment in the defense response.Interestingly,disease resistance genes are highly expressed in landraces of pear but have been selected against during the improvement of this perennial tree species.We found that the genetically diverse landraces can be divided into two subgroups and inferred that they have undergone different dispersal processes.Through co-expression network analysis,we confirmed that the formation of stone cells in pears,the synthesis of fruit anthocyanins,and the ability to resist stress are interrelated.They are jointly regulated by several modules,and the expression of regulatory genes has significant correlations with these three processes.Moreover,we identified candidate genes such as HKL1 that may affect sugar content and are missing from the reference genome.This study provides insights into the associations between complex fruit traits,while providing a database resource for pear disease resistance and fruit quality breeding.展开更多
BACKGROUND: Medulloblastoma is a primitive neuro-ectodermal tumor. It is common in childhood, but rarely seen at adult age, comprising only 1% of primary brain tumors.METHODS: We treated a 31-year-old man presented to...BACKGROUND: Medulloblastoma is a primitive neuro-ectodermal tumor. It is common in childhood, but rarely seen at adult age, comprising only 1% of primary brain tumors.METHODS: We treated a 31-year-old man presented to the emergency department(ED) with a chief complaint of nausea and vomiting for one week duration. Immediate frozen section revealed a grade IV medulloblastoma. During the hospital course, the patient was given craniospinal irradiation with chemotherapy.RESULTS: The patient was eventually discharged from the hospital to an assisted living facility after an uneventful 15-day course with the aid of social work.CONCLUSIONS: Despite intracranial tumors generally being slow growing masses, this patient demonstrates how quickly one can decompensate, and how important it is to recognize these clinical signs and symptoms of an intracranial lesion. Although these symptoms(i.e. Cushing response) are extremely rare, the ED physician should be aware and appreciate their clinical signifi cance.展开更多
The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully el...The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully elucidated.So the taxonomic status and system evolution of the three taxa G.courtoisi,G.galbanus and G.c.simaoensis need to be reclarified.Two gene sequences myoglobin(MYO)and the mitochondrial cytochrome coxidase subunit I(COI)were combined to investigate the phylogenetic relationships among courtoisi,simaoensis and galbanus,genetic data,combining with morphological,ecological and acoustic data were used to comb out the classification status and divergence level of the three taxa.Significant genetic and morphological differentiations(body size and plumage coloration)were detected between courtoisi and galbanus.However,no notable and reliable differences between the courtoisi and simaoensis were detected.The courtoisi,simaoensis and galbanus are clearly isolated in geographical distribution as a result of differing altitudes,climate conditions and habitats.The courtoisi has characteristic preference for nest location compared with galbanus.In addition,the results of song analysis also indicated that there are differences in maximum frequency between courtoisi and galbanus.G.courtoisi was confirmed to be an independent species based on genetic,morphological,geographical,ecological and vocal characteristics,and the validity of simaoensis as a subspecies still need more evidence.This study further confirmed the high conservation value of Blue-crowned Laughingthrush.In addition,due to the genetic differences between Simao and Wuyuan populations,this should be fully considered in future protection strategies.展开更多
Advances in DNA sequencing technology have sparked a genomics revolution,driving breakthroughs in plant genetics and crop breeding.Recently,the focus has shifted from cataloging genetic diversity in plants to explorin...Advances in DNA sequencing technology have sparked a genomics revolution,driving breakthroughs in plant genetics and crop breeding.Recently,the focus has shifted from cataloging genetic diversity in plants to exploring their functional significance and delivering beneficial alleles for crop improvement.This transformation has been facilitated by the increasing adoption of whole-genome resequencing.In this review,we summarize the current progress of population-based genome resequencing studies and how these studies affect crop breeding.A total of 187 land plants from 163 countries have been resequenced,comprising 54413 accessions.As part of resequencing efforts 367 traits have been surveyed and 86 genome-wide association studies have been conducted.Economically important crops,particularly cereals,vegetables,and legumes,have dominated the resequencing efforts,leaving a gap in 49 orders,including Lycopodiales,Liliales,Acorales,Austrobaileyales,and Commelinales.The resequenced germplasm is distributed across diverse geographic locations,providing a global perspective on plant genomics.We highlight genes that have been selected during domestication,or associated with agronomic traits,and form a repository of candidate genes for future research and application.Despite the opportunities for cross-species comparative genomics,many population genomic datasets are not accessible,impeding secondary analyses.We call for a more open and collaborative approach to population genomics that promotes data sharing and encourages contribution-based credit policy.The number of plant genome resequencing studies will continue to rise with the decreasing DNA sequencing costs,coupled with advances in analysis and computational technologies.This expansion,in terms of both scale and quality,holds promise for deeper insights into plant trait genetics and breeding design.展开更多
THE IMPORTANCE OF POLYPLOIDS Polyploids are typically classified as either autopolyploids or allo-polyploids(Figure 1).Autopolyploids result from whole-genome duplication within the same species,while allopolyploids d...THE IMPORTANCE OF POLYPLOIDS Polyploids are typically classified as either autopolyploids or allo-polyploids(Figure 1).Autopolyploids result from whole-genome duplication within the same species,while allopolyploids derive from the hybridization of different species followed by chromo-some doubling.Taxonomically,plant allopolyploids are thought to be the most common polyploids,although autopolyploid plants and allopolyploid plants might be at parity in numbers(Barker et al.,2016).During speciation,polyploidization allows plants to adapt to different environments(Soltis et al.,2009).Mutation and hybridization increase the heterozygosity of the genome,while genome rearrangements during polyploidization lead to the formation of new chromosomes and new chromosome rearrangements,which complicate polyploid genomes and the following studies.展开更多
The realization of a mixed-phase microstructure in strained BiFeO_(3)(BFO)thin films has led to numerous novel effects derived from the coexistence of the tetragonal-like monoclinic phase(T phase)and rhombohedral-like...The realization of a mixed-phase microstructure in strained BiFeO_(3)(BFO)thin films has led to numerous novel effects derived from the coexistence of the tetragonal-like monoclinic phase(T phase)and rhombohedral-like monoclinic phase(R phase).Strong strain and polarization diiferences between the phases should result in a high level of transformation plasticity,which enables the continuous alteration of the relative proportion of R and T states in response to external forces.Although the potential for utilizing such plasticity to control mixed-phase populations under external stimuli is evident,direct experi・mental evidence backed by equilibrium predictions has not yet been fully demonstrated.Here we demonstrate deterministic control of mixed-phase populations in an epitaxially strained BFO thin film through the application of localized stresses and electric fields in a reversible manne匚The results illustrate and rationalize deterministic control of mixed phases in strained BFO films,which could be crucial in tuning their functional properties.The findings also highlight a new multiparametric technique in the scanning probe lithography toolbox based on tip-assisted electric and strain field manipulation of functional properties that might find application beyond the ferroelectric domain and structural phase lithography.展开更多
基金supported by the National Science Foundation of China(32230097)the National Key Research and Development Program of China(2022YFD1200503)+2 种基金the earmarked fund for China Agriculture Research System(CARS-28)the earmarked fund for Jiangsu Agricultural Industry Technology System(JATS[2023]412)the Natural Science Foundation of Jiangsu Province for Young Scholar,China(BK20221010)。
文摘Pyrus pyrifolia,commonly known as sand pear,is a key economic fruit tree in temperate regions that possesses highly diverse germplasm resources for pear quality improvement.However,research on the relationship between resistance and fruit quality traits in the breeding of fruit species like pear is limited.Pan-transcriptomes effectively capture genetic information from coding regions and reflect variations in gene expression between individuals.Here,we constructed a pan-transcriptome based on 506 samples from different tissues of sand pear,and explored the intrinsic relationships among phenotypes and the selection for disease resistance during improvement based on expression presence/absence variations(eP AVs).The pan-transcriptome in this study contains 156,744 transcripts,among which the novel transcripts showed significant enrichment in the defense response.Interestingly,disease resistance genes are highly expressed in landraces of pear but have been selected against during the improvement of this perennial tree species.We found that the genetically diverse landraces can be divided into two subgroups and inferred that they have undergone different dispersal processes.Through co-expression network analysis,we confirmed that the formation of stone cells in pears,the synthesis of fruit anthocyanins,and the ability to resist stress are interrelated.They are jointly regulated by several modules,and the expression of regulatory genes has significant correlations with these three processes.Moreover,we identified candidate genes such as HKL1 that may affect sugar content and are missing from the reference genome.This study provides insights into the associations between complex fruit traits,while providing a database resource for pear disease resistance and fruit quality breeding.
文摘BACKGROUND: Medulloblastoma is a primitive neuro-ectodermal tumor. It is common in childhood, but rarely seen at adult age, comprising only 1% of primary brain tumors.METHODS: We treated a 31-year-old man presented to the emergency department(ED) with a chief complaint of nausea and vomiting for one week duration. Immediate frozen section revealed a grade IV medulloblastoma. During the hospital course, the patient was given craniospinal irradiation with chemotherapy.RESULTS: The patient was eventually discharged from the hospital to an assisted living facility after an uneventful 15-day course with the aid of social work.CONCLUSIONS: Despite intracranial tumors generally being slow growing masses, this patient demonstrates how quickly one can decompensate, and how important it is to recognize these clinical signs and symptoms of an intracranial lesion. Although these symptoms(i.e. Cushing response) are extremely rare, the ED physician should be aware and appreciate their clinical signifi cance.
基金supported by the National Natural Science Foundation of China(No.31660608,31360521)。
文摘The taxonomy of the Blue-crowned Laughingthrush(Garrulax courtoisi)and its relationship with the Yellowthroated Laughingthrush(G.galbanus)and G.c.simaoensis,a range-restricted subspecies in China,has not been fully elucidated.So the taxonomic status and system evolution of the three taxa G.courtoisi,G.galbanus and G.c.simaoensis need to be reclarified.Two gene sequences myoglobin(MYO)and the mitochondrial cytochrome coxidase subunit I(COI)were combined to investigate the phylogenetic relationships among courtoisi,simaoensis and galbanus,genetic data,combining with morphological,ecological and acoustic data were used to comb out the classification status and divergence level of the three taxa.Significant genetic and morphological differentiations(body size and plumage coloration)were detected between courtoisi and galbanus.However,no notable and reliable differences between the courtoisi and simaoensis were detected.The courtoisi,simaoensis and galbanus are clearly isolated in geographical distribution as a result of differing altitudes,climate conditions and habitats.The courtoisi has characteristic preference for nest location compared with galbanus.In addition,the results of song analysis also indicated that there are differences in maximum frequency between courtoisi and galbanus.G.courtoisi was confirmed to be an independent species based on genetic,morphological,geographical,ecological and vocal characteristics,and the validity of simaoensis as a subspecies still need more evidence.This study further confirmed the high conservation value of Blue-crowned Laughingthrush.In addition,due to the genetic differences between Simao and Wuyuan populations,this should be fully considered in future protection strategies.
基金supported by the National Key Research and Development Program of China(2020YFE0202300)Science and Technology Major Project of Guangxi(GuiKeAA20108005-2)+1 种基金Guangdong Innovation Research Team Fund(grant number:2014ZT05S078)National Key Research and Development Program of China(2019YFA0707000).No conflict of interest declared.
文摘Advances in DNA sequencing technology have sparked a genomics revolution,driving breakthroughs in plant genetics and crop breeding.Recently,the focus has shifted from cataloging genetic diversity in plants to exploring their functional significance and delivering beneficial alleles for crop improvement.This transformation has been facilitated by the increasing adoption of whole-genome resequencing.In this review,we summarize the current progress of population-based genome resequencing studies and how these studies affect crop breeding.A total of 187 land plants from 163 countries have been resequenced,comprising 54413 accessions.As part of resequencing efforts 367 traits have been surveyed and 86 genome-wide association studies have been conducted.Economically important crops,particularly cereals,vegetables,and legumes,have dominated the resequencing efforts,leaving a gap in 49 orders,including Lycopodiales,Liliales,Acorales,Austrobaileyales,and Commelinales.The resequenced germplasm is distributed across diverse geographic locations,providing a global perspective on plant genomics.We highlight genes that have been selected during domestication,or associated with agronomic traits,and form a repository of candidate genes for future research and application.Despite the opportunities for cross-species comparative genomics,many population genomic datasets are not accessible,impeding secondary analyses.We call for a more open and collaborative approach to population genomics that promotes data sharing and encourages contribution-based credit policy.The number of plant genome resequencing studies will continue to rise with the decreasing DNA sequencing costs,coupled with advances in analysis and computational technologies.This expansion,in terms of both scale and quality,holds promise for deeper insights into plant trait genetics and breeding design.
基金supported by the Hong Kong Research Grants Council Area of Excellence Scheme(AoE/M-403/16)Collaborative Research Fund(C4057-18EF)+3 种基金CUHK Group Research Scheme 3110135the Innovation and Technology CommissionHong Kong Special Administrative Region Government to the State Key Laboratory of Agrobiotechnology(CUHK)supported by NSF grant IOS-1822330.
文摘THE IMPORTANCE OF POLYPLOIDS Polyploids are typically classified as either autopolyploids or allo-polyploids(Figure 1).Autopolyploids result from whole-genome duplication within the same species,while allopolyploids derive from the hybridization of different species followed by chromo-some doubling.Taxonomically,plant allopolyploids are thought to be the most common polyploids,although autopolyploid plants and allopolyploid plants might be at parity in numbers(Barker et al.,2016).During speciation,polyploidization allows plants to adapt to different environments(Soltis et al.,2009).Mutation and hybridization increase the heterozygosity of the genome,while genome rearrangements during polyploidization lead to the formation of new chromosomes and new chromosome rearrangements,which complicate polyploid genomes and the following studies.
基金UK Research and Innovation,MR/T043172/1Raymond G.P.McQuaid+4 种基金Department for Employment and Learning,Northern Ireland,USI-082Amit KumarEngineering and Physical Sciences Research Council,EP/S037179/1Amit KumarEP/LO15323/01,Nathan Black.
文摘The realization of a mixed-phase microstructure in strained BiFeO_(3)(BFO)thin films has led to numerous novel effects derived from the coexistence of the tetragonal-like monoclinic phase(T phase)and rhombohedral-like monoclinic phase(R phase).Strong strain and polarization diiferences between the phases should result in a high level of transformation plasticity,which enables the continuous alteration of the relative proportion of R and T states in response to external forces.Although the potential for utilizing such plasticity to control mixed-phase populations under external stimuli is evident,direct experi・mental evidence backed by equilibrium predictions has not yet been fully demonstrated.Here we demonstrate deterministic control of mixed-phase populations in an epitaxially strained BFO thin film through the application of localized stresses and electric fields in a reversible manne匚The results illustrate and rationalize deterministic control of mixed phases in strained BFO films,which could be crucial in tuning their functional properties.The findings also highlight a new multiparametric technique in the scanning probe lithography toolbox based on tip-assisted electric and strain field manipulation of functional properties that might find application beyond the ferroelectric domain and structural phase lithography.