Natural rubber(NR)is an irreplaceable biopolymer of economic and strategic importance owing to its unique physical and chemical properties.The Parárubber tree(Hevea brasiliensis(Willd.ex A.Juss.)Müll.Arg.)is...Natural rubber(NR)is an irreplaceable biopolymer of economic and strategic importance owing to its unique physical and chemical properties.The Parárubber tree(Hevea brasiliensis(Willd.ex A.Juss.)Müll.Arg.)is currently the exclusive commercial source of NR,and it is primarily grown in plantations restricted to the tropical and subtropical areas of Southeast Asia.However,current Parárubber production barely meets the sharply increasing global industrial demand for rubber.Petroleum-based synthetic rubber(SR)has been used to supplement the shortage of NR but its industrial performance is not comparable to that of NR.Thus,there is an urgent need to develop new productive rubber crops with broader environmental adaptability.This review summarizes the current research progress on alternative rubberproducing plants,including horticultural plants(Taraxacum kok-saghyz Rodin and Lactuca L.species),woody plants(Parthenium argentatum A.Gray and Eucommia ulmoides Oliv.),and other plant species with potential for NR production.With an emphasis on the molecular basis of NR biosynthesis revealed by a multi-omics approach,we highlight new integrative strategies and biotechnologies for exploring the mechanism of NR biosynthesis with a broader scope,which may accelerate the breeding and improvement of new rubber crops.展开更多
Lipid remodeling is crucial for cold tolerance in plants.However,the precise alternations of lipidomics during cold responses remain elusive,especially in maize(Zea mays L.).In addition,the key genes responsible for c...Lipid remodeling is crucial for cold tolerance in plants.However,the precise alternations of lipidomics during cold responses remain elusive,especially in maize(Zea mays L.).In addition,the key genes responsible for cold tolerance in maize lipid metabolism have not been identified.Here,we integrate lipidomic,transcriptomic,and genetic analysis to determine the profile of lipid remodeling caused by cold stress.We find that the homeostasis of cellular lipid metabolism is essential for maintaining cold tolerance of maize.Also,we detect 210 lipid species belonging to 13 major classes,covering phospholipids,glycerides,glycolipids,and free fatty acids.Various lipid metabolites undergo specific and selective alterations in response to cold stress,especially mono-/di-unsaturated lysophosphatidic acid,lysophosphatidylcholine,phosphatidylcholine,and phosphatidylinositol,as well as polyunsaturated phosphatidic acid,monogalactosyldiacylglycerol,diacylglycerol,and triacylglycerol.In addition,we identify a subset of key enzymes,including ketoacyl-acyl-carrier protein synthase II(KAS II),acyl-carrier protein 2(ACP2),male sterility33(Ms33),and stearoyl-acyl-carrier protein desaturase 2(SAD2)involved in glycerolipid biosynthetic pathways are positive regulators of maize cold tolerance.These results reveal a comprehensive lipidomic profile during the cold response of maize and provide genetic resources for enhancing cold tolerance in crops.展开更多
Heat stress (HS) caused by rapidly warming climate has become a serious threat to global food security.Rice (Oryza sativa L.) is a staple food crop for over half of the world’s population,and its yield and quality ar...Heat stress (HS) caused by rapidly warming climate has become a serious threat to global food security.Rice (Oryza sativa L.) is a staple food crop for over half of the world’s population,and its yield and quality are often reduced by HS.There is an urgent need for breeding heat-tolerant rice cultivars.Rice plants show various morphological and physiological symptoms under HS.Precise analysis of the symptoms(phenotyping) is essential for the selection of elite germplasm and the identification of thermotolerance genes.In response to HS,rice plants trigger a cascade of events and activate complex transcriptional regulatory networks.Protein homeostasis under HS is especially important for rice thermotolerance,which is affected by protein quality control,effective elimination of toxic proteins,and translational regulation.Although some agronomic and genetic approaches for improving heat tolerance have been adopted in rice,the molecular mechanisms underlying rice response to HS are still elusive,and success in engineering rice thermotolerance in breeding has been limited.In this review,we summarize HS-caused symptoms in rice and progress in heat-stress sensing and signal cascade research,and propose approaches for improving rice thermotolerance in future.展开更多
Rice grain yield is determined by three major"visible"morphological traits:grain weight,grain number per panicle,and effective tiller number,which are affected by a series of"invisible"physiologica...Rice grain yield is determined by three major"visible"morphological traits:grain weight,grain number per panicle,and effective tiller number,which are affected by a series of"invisible"physiological factors including nutrient use efficiency and photosynthetic efficiency.In the past few decades,substantial progress has been made on elucidating the molecular mechanisms underlying grain yield formation,laying a solid foundation for improving rice yield by molecular breeding.This review outlines our current understanding of the three morphological yield-determining components and summarizes major progress in decoding physiological traits such as nutrient use efficiency and photosynthetic efficiency.It also discusses the integration of current knowledge about yield formation and crop improvement strategies including genome editing with conventional and molecular breeding.展开更多
The wild rice species in the genus Oryza harbor a large amount of genetic diversity that has been untapped for rice improvement.Pan-genomics has revolutionized genomic research in plants.However,rice pan-genomic studi...The wild rice species in the genus Oryza harbor a large amount of genetic diversity that has been untapped for rice improvement.Pan-genomics has revolutionized genomic research in plants.However,rice pan-genomic studies so far have been limited mostly to cultivated accessions,with only a few close wild relatives.Advances in sequencing technologies have permitted the assembly of highquality rice genome sequences at low cost,making it possible to construct genus-level pan-genomes across all species.In this review,we summarize progress in current research on genetic and genomic resources in Oryza,and in sequencing and computational technologies used for rice genome and pangenome construction.For future work,we discuss the approaches and challenges in the construction of,and data access to,Oryza pan-genomes based on representative high-quality genome assemblies.The Oryza pan-genomes will provide a basis for the exploration and use of the extensive genetic diversity present in both cultivated and wild rice populations.展开更多
In order to obtain marker-free transgenic rice with improved disease resistance, the AP1 gene of Capsicum annuum and hygromycin-resistance gene (HPT) were cloned into the two separate T-DNA regions of the binary vec...In order to obtain marker-free transgenic rice with improved disease resistance, the AP1 gene of Capsicum annuum and hygromycin-resistance gene (HPT) were cloned into the two separate T-DNA regions of the binary vector pSB130, respectively, and introduced into the calli derived from the immature seeds of two elite japonica rice varieties, Guangling Xiangjing and Wuxiangjing 9, mediated by Agrobacterium-mediated transformation. Many cotransgenic rice lines containing both the AP1 gene and the marker gene were regenerated and the integration of both transgenes in the transgenic rice plants was confirmed by either PCR or Southern blotting technique. Several selectable marker-free transgenic rice plants were subsequently obtained from the progeny of the cotransformants, and confirmed by both PCR and Southern blotting analysis. These transgenic rice lines were tested in the field and their resistance to disease was carefully investigated, the results showed that after inoculation the resistance to either bacterial blight or sheath blight of the selected transgenic lines was improved when compared with those of wild type.展开更多
Phosphate deficiency is one of the leading causes of crop productivity loss.Phospholipid degradation liberates phosphate to cope with phosphate deficiency.Glycerophosphodiester phosphodiesterases(GPX-PDEs)hydrolyse th...Phosphate deficiency is one of the leading causes of crop productivity loss.Phospholipid degradation liberates phosphate to cope with phosphate deficiency.Glycerophosphodiester phosphodiesterases(GPX-PDEs)hydrolyse the intermediate products of phospholipid catabolism glycerophosphodiesters into glycerol-3-phosphate,a precursor of phosphate.However,the function of GPX-PDEs in phosphate remobilization in maize remains unclear.In the present study,we characterized two phosphate deficiency-inducible GPX-PDE genes,ZmGPX-PDE1 and ZmGPX-PDE5,in maize leaves.ZmGPX-PDE1 and ZmGPX-PDE5 were transcriptionally regulated by ZmPHR1,a well-described phosphate starvation-responsive transcription factor of the MYB family.Complementation of the yeast GPX-PDE mutant gde1Δindicated that ZmGPX-PDE1 and ZmGPX-PDE5 functioned as GPX-PDEs,suggesting their roles in phosphate recycling from glycerophosphodiesters.In vitro enzyme assays showed that ZmGPX-PDE1 and ZmGPX-PDE5 catalysed glycerophosphodiester degradation with different substrate preferences for glycerophosphoinositol and glycerophosphocholine,respectively.ZmGPX-PDE1 was upregulated during leaf senescence,and more remarkably,loss of ZmGPXPDE1 inmaize compromised the remobilization of phosphorus fromsenescing leaves to young leaves,resulting in a stay-green phenotype under phosphate starvation.These results suggest that ZmGPX-PDE1 catalyses the degradation of glycerophosphodiesters in maize,promoting phosphate recycling from senescing leaves to new leaves.This mechanism is crucial for improving phosphorus utilization efficiency in crops.展开更多
The tomato encode four functional DCL families,of which DCL2 is poorly studied.Here,we generated loss-of-function mutants for a tomato DCL2 gene,dcl2b,and we identified its major role in defending against tomato mosai...The tomato encode four functional DCL families,of which DCL2 is poorly studied.Here,we generated loss-of-function mutants for a tomato DCL2 gene,dcl2b,and we identified its major role in defending against tomato mosaic virus in relation to both natural and manual infections.Genome-wide small RNA expression profiling revealed that DCL2b was required for the processing 22-nt small RNAs,including a few species of miRNAs.Interestingly,these DCL2b-dependent 22-nt miRNAs functioned similarly to the DCL1-produced 22-nt miRNAs in Arabidopsis and could serve as triggers to generate a class of secondary siRNAs.In particular,the majority of secondary siRNAs were derived from plant defense genes when the plants were challenged with viruses.We also examined differentially expressed genes in dcl2b through RNA-seq and observed that numerous genes were associated with mitochondrial metabolism and hormone signaling under virus-free conditions.Notably,when the loss-of-function dcl2b mutant was challenged with tomato mosaic virus,a group of defense response genes was activated,whereas the genes related to lipid metabolism were suppressed.Together,our findings provided new insights into the roles of tomato DCL2b in small RNA biogenesis and in antiviral defense.展开更多
CRISPR-Cas12a offers a convenient tool for multiplex genome editing in rice. However, the CRISPR-Cas12a system displays variable editing efficiency across genomic loci, with marked influence by CRISPR RNAs(crRNAs). To...CRISPR-Cas12a offers a convenient tool for multiplex genome editing in rice. However, the CRISPR-Cas12a system displays variable editing efficiency across genomic loci, with marked influence by CRISPR RNAs(crRNAs). To improve the efficiency of the CRISPR-Cas12a system for multiplex genome editing, we identified various architectures and expression strategies for crRNAs. Transformation of binary vectors loaded with engineered CRISPR-Cas12a systems into rice calli and subsequent sequencing revealed that a modified tRNA-crRNA array not only efficiently achieved rice multiplex genome editing, but also successfully edited target sites that were not edited by the crRNA array. This improvement contributes to the application of the CRISPR-Cas12a system in plant genome editing, especially for genomic loci that have hitherto been difficult to edit.展开更多
Objective Unbiased next generation sequencing(NGS) is susceptible to interference from host or environmental sequences. Consequently, background depletion and virome enrichment techniques are usually needed for clin...Objective Unbiased next generation sequencing(NGS) is susceptible to interference from host or environmental sequences. Consequently, background depletion and virome enrichment techniques are usually needed for clinical samples where viral load is much lower than background sequences. Methods A viral Sequence Independent Targeted Amplification(VSITA) approach using a set of non-ribosomal and virus-enriched octamers(V8) was developed and compared with traditionally used random hexamers(N6). Forty-five archived clinical samples of different types were used in parallel to compare the V8 and N6 enrichment performance of viral sequences and removal performance of ribosomal sequences in the step of reverse transcription followed by quantitative PCR(qP CR). Ten sera samples from patients with fever of unknown origin and 10 feces samples from patients with diarrhea of unknown origin were used in comparison of V8 and N6 enrichment performance following NGS analysis. Results A minimum 30 hexamers matching to viral reference sequences(sense and antisense) were selected from a dataset of random 4,096(4~6) hexamers(N6). Two random nucleotides were added to the 5' end of the selected hexamers, and 480(30 × 4~2) octamers(V8) were obtained. In general, VSITA approach showed higher enrichment of virus-targeted c DNA and enhanced ability to remove unwanted ribosomal sequences in the majorities of 45 predefined clinical samples. Moreover, VSITA combined with NGS enabled to detect not only more viruses but also achieve more viral reads hit and higher viral genome coverage in 20 clinical samples with diarrhea or fever of unknown origin. Conclusion The VSITA approach designed in this study is demonstrated to possess higher sensitivity and broader genome coverage than traditionally used random hexamers in the NGS-based identification of viral pathogens directly from clinical samples.展开更多
A mutant of panicle differentiation in rice called non-panicle (nop) was discovered in the progeny of a cross between 93-11 and Nipponbare. The mutant exhibits normal plant morphology but has apparently few tillers....A mutant of panicle differentiation in rice called non-panicle (nop) was discovered in the progeny of a cross between 93-11 and Nipponbare. The mutant exhibits normal plant morphology but has apparently few tillers. The most striking change in nop is that its panicle differentiation is blocked, with masses of fluffy bract nodes generate from the positions where rachis branches normally develop in wild-type plants. Genetic analysis suggests that nop is controlled by a single recessive gene, which is temporarily named Nop(t). Based on its mutant phenotype, Nop(t) represents a key gene controlling the initiation of inflorescence differentiation, By using simple sequence repeat markers and sequence tagged site markers, Nop(t) gene was fine mapped in a 102-kb interval on the long arm of chromosome 6. These results will facilitate the positional cloning and functional studies of the gene.展开更多
Background:Cotton somatic embryogenesis is difficult or rarely frequent to present,which has limited gene function identification and biotechnological utility.Here,we employed a rice key somatic embryogenesis-related ...Background:Cotton somatic embryogenesis is difficult or rarely frequent to present,which has limited gene function identification and biotechnological utility.Here,we employed a rice key somatic embryogenesis-related gene,rice lesion simulating disease 1-like gene(OsLOL1),to develop transgenic cotton callus for evaluating its function in ectopic plants.Results:Overexpressing OsLOL1 can promote cotton callus to form embryogenic callus,not only shortening time but also increasing transition of somatic callus cells to embryogenic callus cells.And the regenerating plantlets per transgenic OsLOL1 embryogenic callus were significantly higher than those in the control transformed with empty vector.Analysis of physiological and biochemical showed that OsLOL1 can repress cotton superoxide dismutase 1 gene(GhSOD1)expression,possibly resulting in reactive oxidant species(ROS)accumulation in transgenic callus cells.And OsLOL1-overexpressed embryogenic callus exhibited higherα-amylase activity compared with the control,resulting from the promotion of OsLOL1 to cotton amylase 7 gene(GhAmy7)and GhAmy8 expression.Conclusion:The data showed that OsLOL1 could be used as a candidate gene to transform cotton to increase its somatic embryogenesis capacity,facilitating gene function analysis and molecular breeding in cotton.展开更多
基金We thank Dr Gary Loake (University of Edinburgh, UK) for providing gsnor1-3 seeds. We are grateful to Drs Chuanyou Li, Shuhua Yang and Yiqin Wang for critically reading the manuscript. This study was supported by grants from the National Natural Science Foundation of China (30330360), the Ministry of Science and Technology of China (2006AA 10A 112) and the Chinese Academy of Sciences (KSCX2-YW-N-015).
基金This work was supported by the National Key Research and Development Program of China(2019YFD1002701-02)the National Natural Science Foundation of China(32170371)the Strategic Priority Research Program of Chinese Academy of Sciences(XDA24030503).
文摘Natural rubber(NR)is an irreplaceable biopolymer of economic and strategic importance owing to its unique physical and chemical properties.The Parárubber tree(Hevea brasiliensis(Willd.ex A.Juss.)Müll.Arg.)is currently the exclusive commercial source of NR,and it is primarily grown in plantations restricted to the tropical and subtropical areas of Southeast Asia.However,current Parárubber production barely meets the sharply increasing global industrial demand for rubber.Petroleum-based synthetic rubber(SR)has been used to supplement the shortage of NR but its industrial performance is not comparable to that of NR.Thus,there is an urgent need to develop new productive rubber crops with broader environmental adaptability.This review summarizes the current research progress on alternative rubberproducing plants,including horticultural plants(Taraxacum kok-saghyz Rodin and Lactuca L.species),woody plants(Parthenium argentatum A.Gray and Eucommia ulmoides Oliv.),and other plant species with potential for NR production.With an emphasis on the molecular basis of NR biosynthesis revealed by a multi-omics approach,we highlight new integrative strategies and biotechnologies for exploring the mechanism of NR biosynthesis with a broader scope,which may accelerate the breeding and improvement of new rubber crops.
基金supported by grants from the State Key Project of Research and Development Plan(2022YFF1001603)the National Natural Science Foundation of China(32022008,32272025,and 31921001)the Chinese Universities Scientific Fund(2022TC137 and 2023TC019).
文摘Lipid remodeling is crucial for cold tolerance in plants.However,the precise alternations of lipidomics during cold responses remain elusive,especially in maize(Zea mays L.).In addition,the key genes responsible for cold tolerance in maize lipid metabolism have not been identified.Here,we integrate lipidomic,transcriptomic,and genetic analysis to determine the profile of lipid remodeling caused by cold stress.We find that the homeostasis of cellular lipid metabolism is essential for maintaining cold tolerance of maize.Also,we detect 210 lipid species belonging to 13 major classes,covering phospholipids,glycerides,glycolipids,and free fatty acids.Various lipid metabolites undergo specific and selective alterations in response to cold stress,especially mono-/di-unsaturated lysophosphatidic acid,lysophosphatidylcholine,phosphatidylcholine,and phosphatidylinositol,as well as polyunsaturated phosphatidic acid,monogalactosyldiacylglycerol,diacylglycerol,and triacylglycerol.In addition,we identify a subset of key enzymes,including ketoacyl-acyl-carrier protein synthase II(KAS II),acyl-carrier protein 2(ACP2),male sterility33(Ms33),and stearoyl-acyl-carrier protein desaturase 2(SAD2)involved in glycerolipid biosynthetic pathways are positive regulators of maize cold tolerance.These results reveal a comprehensive lipidomic profile during the cold response of maize and provide genetic resources for enhancing cold tolerance in crops.
基金We would like to thank Dr Nam-Hai Chua (Rockefeller Univer- sity) for kindly providing the pBA002Myc vector and the Arabi- dopsis Biological Resource Center (ABRC), Ohio State University for providing ToDNA insertion lines. This work was supported by grants from National Natural Science Foundation of China (No. 30530400/90717006/30670195) to Q Xie and Y Wu, the Chinese Academy of Science (KSCX2-YW-N-010 and CXTD-S2005-2), and the (iuangdong Natural Science Foundation, China (No. 5300648) to Z Deng.
基金Acknowledgments We are grateful to Dr Xinnian Dong (Duke University, Durham, NC, USA) for critical reading of the manuscript and valuable suggestions. We thank Dr Jianmin Zhou (National Institute of Biological Sciences, Beijing, China) for providing the fungus strain Botrytis cinerea, Dr Salome Prat (Institut de Biologia Molecular de Barcelona, Barcelona, Spain) for providing homozygous atmyc2-2 (T-DNA insertion line SALK_083483) seeds and Dr Daoxin Xie (Tsinghua University, Beijing, China) for providing the coil-I seeds. This work was supported by grants from The National Natural Science Foundation of China (30530440), The Ministry of Science and Technology of China (2006CB 102004, 2006AA10A 116), and The Chinese Academy of Sciences (KSCX2-YW-N-045).
基金supported by the National Key Research and Development Program of China (2016YFD0101801)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA24030201)the State Key Laboratory of Plant Genomics。
文摘Heat stress (HS) caused by rapidly warming climate has become a serious threat to global food security.Rice (Oryza sativa L.) is a staple food crop for over half of the world’s population,and its yield and quality are often reduced by HS.There is an urgent need for breeding heat-tolerant rice cultivars.Rice plants show various morphological and physiological symptoms under HS.Precise analysis of the symptoms(phenotyping) is essential for the selection of elite germplasm and the identification of thermotolerance genes.In response to HS,rice plants trigger a cascade of events and activate complex transcriptional regulatory networks.Protein homeostasis under HS is especially important for rice thermotolerance,which is affected by protein quality control,effective elimination of toxic proteins,and translational regulation.Although some agronomic and genetic approaches for improving heat tolerance have been adopted in rice,the molecular mechanisms underlying rice response to HS are still elusive,and success in engineering rice thermotolerance in breeding has been limited.In this review,we summarize HS-caused symptoms in rice and progress in heat-stress sensing and signal cascade research,and propose approaches for improving rice thermotolerance in future.
基金We thank Prof Joanne Chory (The Salk Institute for Biological Studies, USA) for providing the Arabidopsis bril-101 mutant seeds. This work was supported by grants from the National Natural Science Foundation of China (grant numbers: 30070074, 30330040 and 30570161).
基金We thank Dr Ottoline Leyser (University of York, UK) for providing axrl-3 and Dr Mark Estelle (UC, San Diego, USA) for providing tirlafb2afb3 triple mutant seeds. This work was supported by a grant from the National Natural Science Foundation of China (30830009).
基金supported by the National Natural Science Foundation of China(31901520)Top Talent Foundation of Sichuan Academy of Agricultural Sciences(2020BJRC008)。
文摘Rice grain yield is determined by three major"visible"morphological traits:grain weight,grain number per panicle,and effective tiller number,which are affected by a series of"invisible"physiological factors including nutrient use efficiency and photosynthetic efficiency.In the past few decades,substantial progress has been made on elucidating the molecular mechanisms underlying grain yield formation,laying a solid foundation for improving rice yield by molecular breeding.This review outlines our current understanding of the three morphological yield-determining components and summarizes major progress in decoding physiological traits such as nutrient use efficiency and photosynthetic efficiency.It also discusses the integration of current knowledge about yield formation and crop improvement strategies including genome editing with conventional and molecular breeding.
基金supported by Chinese Academy of Sciences"Strategic Priority Research Program"(XDA24040201)National Key Research and Development Program of China(2020YFE0202300)State Key Laboratory of Plant Genomics。
文摘The wild rice species in the genus Oryza harbor a large amount of genetic diversity that has been untapped for rice improvement.Pan-genomics has revolutionized genomic research in plants.However,rice pan-genomic studies so far have been limited mostly to cultivated accessions,with only a few close wild relatives.Advances in sequencing technologies have permitted the assembly of highquality rice genome sequences at low cost,making it possible to construct genus-level pan-genomes across all species.In this review,we summarize progress in current research on genetic and genomic resources in Oryza,and in sequencing and computational technologies used for rice genome and pangenome construction.For future work,we discuss the approaches and challenges in the construction of,and data access to,Oryza pan-genomes based on representative high-quality genome assemblies.The Oryza pan-genomes will provide a basis for the exploration and use of the extensive genetic diversity present in both cultivated and wild rice populations.
基金This paper is translated from its Chinese version in Scientia Agricultura Sinica.This study was supported by the Government of Jiangsu Province,China(BG2002301 and JH02-106)National Transgenic Plant R&D Project(JY03-B-10)+1 种基金National Natural Science Foundation of China(30170567)Department of Education of Jiangsu Goverment,China(K05015).
文摘In order to obtain marker-free transgenic rice with improved disease resistance, the AP1 gene of Capsicum annuum and hygromycin-resistance gene (HPT) were cloned into the two separate T-DNA regions of the binary vector pSB130, respectively, and introduced into the calli derived from the immature seeds of two elite japonica rice varieties, Guangling Xiangjing and Wuxiangjing 9, mediated by Agrobacterium-mediated transformation. Many cotransgenic rice lines containing both the AP1 gene and the marker gene were regenerated and the integration of both transgenes in the transgenic rice plants was confirmed by either PCR or Southern blotting technique. Several selectable marker-free transgenic rice plants were subsequently obtained from the progeny of the cotransformants, and confirmed by both PCR and Southern blotting analysis. These transgenic rice lines were tested in the field and their resistance to disease was carefully investigated, the results showed that after inoculation the resistance to either bacterial blight or sheath blight of the selected transgenic lines was improved when compared with those of wild type.
基金supported by the National Key Research and Development Program of China(2017YFD0200204)the National Natural Science Foundation of China(31972496,31572190)+1 种基金the Deutsche Forschungsgemeinschaft(328017493/GRK2366)the National Institutes of Health Grant(R15 GM 104876)to Jana Patton-Vogt。
文摘Phosphate deficiency is one of the leading causes of crop productivity loss.Phospholipid degradation liberates phosphate to cope with phosphate deficiency.Glycerophosphodiester phosphodiesterases(GPX-PDEs)hydrolyse the intermediate products of phospholipid catabolism glycerophosphodiesters into glycerol-3-phosphate,a precursor of phosphate.However,the function of GPX-PDEs in phosphate remobilization in maize remains unclear.In the present study,we characterized two phosphate deficiency-inducible GPX-PDE genes,ZmGPX-PDE1 and ZmGPX-PDE5,in maize leaves.ZmGPX-PDE1 and ZmGPX-PDE5 were transcriptionally regulated by ZmPHR1,a well-described phosphate starvation-responsive transcription factor of the MYB family.Complementation of the yeast GPX-PDE mutant gde1Δindicated that ZmGPX-PDE1 and ZmGPX-PDE5 functioned as GPX-PDEs,suggesting their roles in phosphate recycling from glycerophosphodiesters.In vitro enzyme assays showed that ZmGPX-PDE1 and ZmGPX-PDE5 catalysed glycerophosphodiester degradation with different substrate preferences for glycerophosphoinositol and glycerophosphocholine,respectively.ZmGPX-PDE1 was upregulated during leaf senescence,and more remarkably,loss of ZmGPXPDE1 inmaize compromised the remobilization of phosphorus fromsenescing leaves to young leaves,resulting in a stay-green phenotype under phosphate starvation.These results suggest that ZmGPX-PDE1 catalyses the degradation of glycerophosphodiesters in maize,promoting phosphate recycling from senescing leaves to new leaves.This mechanism is crucial for improving phosphorus utilization efficiency in crops.
基金This research was supported by grants from the National Natural Science Foundation of China(31471921,91540118,31622050,and 31672208)to H.ZT.W.was supported by a fellowship from the Chinese Scholarship Council.
文摘The tomato encode four functional DCL families,of which DCL2 is poorly studied.Here,we generated loss-of-function mutants for a tomato DCL2 gene,dcl2b,and we identified its major role in defending against tomato mosaic virus in relation to both natural and manual infections.Genome-wide small RNA expression profiling revealed that DCL2b was required for the processing 22-nt small RNAs,including a few species of miRNAs.Interestingly,these DCL2b-dependent 22-nt miRNAs functioned similarly to the DCL1-produced 22-nt miRNAs in Arabidopsis and could serve as triggers to generate a class of secondary siRNAs.In particular,the majority of secondary siRNAs were derived from plant defense genes when the plants were challenged with viruses.We also examined differentially expressed genes in dcl2b through RNA-seq and observed that numerous genes were associated with mitochondrial metabolism and hormone signaling under virus-free conditions.Notably,when the loss-of-function dcl2b mutant was challenged with tomato mosaic virus,a group of defense response genes was activated,whereas the genes related to lipid metabolism were suppressed.Together,our findings provided new insights into the roles of tomato DCL2b in small RNA biogenesis and in antiviral defense.
基金funded by the National Key Research and Development Program of China(2016YFD0101800)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciencesthe National GMO New Variety Breeding Program of China(2016ZX08011-001)。
文摘CRISPR-Cas12a offers a convenient tool for multiplex genome editing in rice. However, the CRISPR-Cas12a system displays variable editing efficiency across genomic loci, with marked influence by CRISPR RNAs(crRNAs). To improve the efficiency of the CRISPR-Cas12a system for multiplex genome editing, we identified various architectures and expression strategies for crRNAs. Transformation of binary vectors loaded with engineered CRISPR-Cas12a systems into rice calli and subsequent sequencing revealed that a modified tRNA-crRNA array not only efficiently achieved rice multiplex genome editing, but also successfully edited target sites that were not edited by the crRNA array. This improvement contributes to the application of the CRISPR-Cas12a system in plant genome editing, especially for genomic loci that have hitherto been difficult to edit.
基金supported by grants from the National key research and development plan of China[2016TFC1202700,2016YFC1200903,and 2017YFC1200503]China Mega-Project for Infectious Disease[2017ZX10302301-004,2017ZX100101,and 2017ZX10104001]
文摘Objective Unbiased next generation sequencing(NGS) is susceptible to interference from host or environmental sequences. Consequently, background depletion and virome enrichment techniques are usually needed for clinical samples where viral load is much lower than background sequences. Methods A viral Sequence Independent Targeted Amplification(VSITA) approach using a set of non-ribosomal and virus-enriched octamers(V8) was developed and compared with traditionally used random hexamers(N6). Forty-five archived clinical samples of different types were used in parallel to compare the V8 and N6 enrichment performance of viral sequences and removal performance of ribosomal sequences in the step of reverse transcription followed by quantitative PCR(qP CR). Ten sera samples from patients with fever of unknown origin and 10 feces samples from patients with diarrhea of unknown origin were used in comparison of V8 and N6 enrichment performance following NGS analysis. Results A minimum 30 hexamers matching to viral reference sequences(sense and antisense) were selected from a dataset of random 4,096(4~6) hexamers(N6). Two random nucleotides were added to the 5' end of the selected hexamers, and 480(30 × 4~2) octamers(V8) were obtained. In general, VSITA approach showed higher enrichment of virus-targeted c DNA and enhanced ability to remove unwanted ribosomal sequences in the majorities of 45 predefined clinical samples. Moreover, VSITA combined with NGS enabled to detect not only more viruses but also achieve more viral reads hit and higher viral genome coverage in 20 clinical samples with diarrhea or fever of unknown origin. Conclusion The VSITA approach designed in this study is demonstrated to possess higher sensitivity and broader genome coverage than traditionally used random hexamers in the NGS-based identification of viral pathogens directly from clinical samples.
基金supported by the grants from the National Natural Science Foundation of China (Grant No.30300196 and No. 30771160)the State Key Basic Research Program of China (Grant No.2007CB10920203)the Research Program of Zhejiang Province,China
文摘A mutant of panicle differentiation in rice called non-panicle (nop) was discovered in the progeny of a cross between 93-11 and Nipponbare. The mutant exhibits normal plant morphology but has apparently few tillers. The most striking change in nop is that its panicle differentiation is blocked, with masses of fluffy bract nodes generate from the positions where rachis branches normally develop in wild-type plants. Genetic analysis suggests that nop is controlled by a single recessive gene, which is temporarily named Nop(t). Based on its mutant phenotype, Nop(t) represents a key gene controlling the initiation of inflorescence differentiation, By using simple sequence repeat markers and sequence tagged site markers, Nop(t) gene was fine mapped in a 102-kb interval on the long arm of chromosome 6. These results will facilitate the positional cloning and functional studies of the gene.
基金the Natural Science Foundation of China(31971905 and 31771848)the State Key Laboratory of Cotton Biology Open Fund(CB2019B02).
文摘Background:Cotton somatic embryogenesis is difficult or rarely frequent to present,which has limited gene function identification and biotechnological utility.Here,we employed a rice key somatic embryogenesis-related gene,rice lesion simulating disease 1-like gene(OsLOL1),to develop transgenic cotton callus for evaluating its function in ectopic plants.Results:Overexpressing OsLOL1 can promote cotton callus to form embryogenic callus,not only shortening time but also increasing transition of somatic callus cells to embryogenic callus cells.And the regenerating plantlets per transgenic OsLOL1 embryogenic callus were significantly higher than those in the control transformed with empty vector.Analysis of physiological and biochemical showed that OsLOL1 can repress cotton superoxide dismutase 1 gene(GhSOD1)expression,possibly resulting in reactive oxidant species(ROS)accumulation in transgenic callus cells.And OsLOL1-overexpressed embryogenic callus exhibited higherα-amylase activity compared with the control,resulting from the promotion of OsLOL1 to cotton amylase 7 gene(GhAmy7)and GhAmy8 expression.Conclusion:The data showed that OsLOL1 could be used as a candidate gene to transform cotton to increase its somatic embryogenesis capacity,facilitating gene function analysis and molecular breeding in cotton.