Although several pentatricopeptide repeat(PPR) proteins are involved in post-transcriptional processing of mitochondrial RNA, it is unclear which specific protein is involved in the RNA editing of ccmC in maize(Zea ma...Although several pentatricopeptide repeat(PPR) proteins are involved in post-transcriptional processing of mitochondrial RNA, it is unclear which specific protein is involved in the RNA editing of ccmC in maize(Zea mays). Here we report the identification of the maize empty pericarp 601(emp601) mutant and the map-based cloning of the Emp601 gene, which encodes an E2-type PPR protein that is targeted to mitochondria. A single-nucleotide deletion in the emp601 mutant caused a frameshift and introduced a premature stop codon into the predicted EMP601. This mutation was associated with reduced accumulation of mitochondrial complex Ⅲ as well as with inhibition of growth and differentiation of basal endosperm transfer layer cells, leading to final degeneration of the embryo and endosperm. We determine that loss of EMP601 function prevents the C-to-U RNA editing of the mitochondrial transcript ccmC at position 358.EMP601 binds to the ccmC transcript and directly interacts with Multiple organellar RNA editing factor 8and may be a component of the plant mitochondrial editosome. We conclude that EMP601 functions in RNA editing of mitochondrial ccmC transcripts and influences mitochondrial function and seed development.展开更多
Zinc(Zn) is an essential mineral element for plant growth and development. Zn deficiency in crops frequently occurs in many types of soils. It is therefore crucial to identify genetic resources linking Zn acquisition ...Zinc(Zn) is an essential mineral element for plant growth and development. Zn deficiency in crops frequently occurs in many types of soils. It is therefore crucial to identify genetic resources linking Zn acquisition traits and development of crops with improved Zn-use efficiency for sustainable crop production. In this study, we functionally identified a rice uncharacterized ABCG(ATP-binding cassette G-subfamily) gene encoding a PDR20(pleiotropic drug resistance 20) metal transporter for mediation of rice growth, seed development and Zn accumulation. OsPDR20 was localized to the plasma membrane, but it was not transcriptionally induced under Zn deficiency, rather was sufficiently up-regulated under high level of Zn stress. Yeast(Saccharomyces cerevisiae) transformed with OsPDR20 displayed a relatively lower Zn accumulation with attenuated cellular growth, suggesting that OsPDR20 had an activity for Zn transport. Knocking-down OsPDR20 by RNA interference(RNAi) compromised rice growth with shorter plant height and decreased biomass in rice plantlets grown under hydroponic media. Zn concentration in the roots of OsPDR20 knocked-down rice lines declined under Zn deficiency, while they remained unchanged compared with the wild type under normal Zn supply. A rice lifelong field trial demonstrated that OsPDR20 mutation impaired the capacity of seed development, with shortened panicle and seed length, compromised spikelet fertility, and reduced grain number per plant or grain weight per unit area. Interestingly, OsPDR20 mutation elevated the accumulation of Zn in husk and brown rice over the wild type. Overall, this study pointed out that OsPDR20 is fundamentally required for rice growth and seed development through Zn transport and homeostasis.展开更多
The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelo...The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelon, a valued and nutritious fruit, remain largely unknown and their functions have not been characterized. In the present study, 22 ClNF-Y genes in watermelon, 29 CsNF-Y genes in cucumber, and 24CmNF-Y genes in melon were identified based on the whole-genome investigation and their protein properties, gene location, gene structure, motif composition, conserved domain, and evolutionary relationship were investigated. ClNF-YB9 from watermelon and its homologs in cucumber and melon were expressed specifically in seeds. Its expression remained low in the early stages of watermelon seed development,increased at 20 days after pollination(DAP), and peaked at 45–50 DAP. Moreover, the knockout mutant Clnf-yb9 exhibited abnormal leafy cotyledon phenotype, implying its critical role during seed formation.Finally, protein interaction assays showed that ClNF-YB9 interacts with all ClNF-YCs and the ClNF-YB9-YC4 heterodimer was able to recruit a ClNF-YA7 subunit to assemble a complete NF-Y complex, which may function in seed development. This study revealed the structure and evolutionary relationships of the NF-Y gene family in Cucurbitaceae and the novel function of ClNF-YB9 in regulating seed development in watermelon.展开更多
ABA is one of the 5 phytohormones in higher plants, which is also the most important hormone that regulates higher plants in response to environmental stress, by ABA signal transduction. Understanding ABA signal trans...ABA is one of the 5 phytohormones in higher plants, which is also the most important hormone that regulates higher plants in response to environmental stress, by ABA signal transduction. Understanding ABA signal transduction at the molecular level is crucial to biology and ecology, and rational breeding complied with corresponding eco-environmental changes. Great advancements have taken place over the past 10 years by application of the Arabidopsis experimental system. Many components involved in ABA signal transduction have been isolated and identified and a clear overall picture of gene expression and control for this transduction has become an accepted fact. On the basis of the work in our laboratory, in conjunction with the data available at the moment, the authors have attempted to integrate ABA signal transduction pathways into a common one and give some insights into the relationship between ABA signal transduction and other hormone signal transduction pathways, with an emphasis upon the ABA signal transduction during higher plant seed development. A future challenge in this field is that different experimental systems are applied and various receptors and genes need to be characterized through the utilization of microarray chips.展开更多
The B3 transcription factors(TFs)in plants play vital roles in numerous biological processes.Although B3 genes have been broadly identified in many plants,little is known about their potential functions in mediating s...The B3 transcription factors(TFs)in plants play vital roles in numerous biological processes.Although B3 genes have been broadly identified in many plants,little is known about their potential functions in mediating seed development and material accumulation.Castor bean(Ricinus communis)is a non-edible oilseed crop considered an ideal model system for seed biology research.Here,we identified a total of 61 B3 genes in the castor bean genome,which can be classified into five subfamilies,including ABI3/VP1,HSI,ARF,RAV and REM.The expression profiles revealed that RcABI3/VP1 subfamily genes are significantly up-regulated in the middle and later stages of seed development,indicating that these genes may be associated with the accumulation of storage oils.Furthermore,through yeast one-hybrid and tobacco transient expression assays,we detected that ABI3/VP1 subfamily member RcLEC2 directly regulates the transcription of RcOleosin2,which encodes an oil-body structural protein.This finding suggests that RcLEC2,as a seed-specific TF,may be involved in the regulation of storage materials accumulation.This study provides novel insights into the potential roles and molecular basis of B3 family proteins in seed development and material accumulation.展开更多
Interaction between the embryo and endosperm affects seed development,an essential process in yield formation in crops such as rice.Signals that mediate communication between embryo and endosperm are largely unknown.W...Interaction between the embryo and endosperm affects seed development,an essential process in yield formation in crops such as rice.Signals that mediate communication between embryo and endosperm are largely unknown.We used the notched-belly(NB)mutant with impaired communication between embryo and endosperm to investigate the effect of the embryo on developmental staging of the endosperm and signaling pathways in the embryo that regulate endosperm development.Hierachical clustering of m RNA datasets from embryo and endosperm samples collected during development in NB and a wild type showed a delaying effect of the embryo on the developmental transition of the endosperm by extension of the middle stage.K-means clustering further identified coexpression modules of gene sets specific to embryo and endosperm development.Combined gene expression and biochemical analysis showed that T6 P–Sn RK1,gibberellin and auxin signaling by the embryo regulate endosperm developmental transition.We propose a new seed developmental staging system for rice and identify the most detailed signature of rice grain formation to date.These will direct genetic strategies for rice yield improvement.展开更多
RNA helicases participate in nearly all aspects of RNA metabolism by rearranging RNAs or RNA–protein complexes in an adenosine triphosphatedependent manner.Due to the large RNA helicase families in plants,the precise...RNA helicases participate in nearly all aspects of RNA metabolism by rearranging RNAs or RNA–protein complexes in an adenosine triphosphatedependent manner.Due to the large RNA helicase families in plants,the precise roles of many RNA helicases in plant physiology and development remain to be clarified.Here,we show that mutations in maize(Zea mays)DEAD-box RNA helicase48(Zm RH48)impair the splicing of mitochondrial introns,mitochondrial complex biosynthesis,and seed development.Loss of Zm RH48 function severely arrested embryogenesis and endosperm development,leading to defective kernel formation.Zm RH48 is targeted to mitochondria,where its deficiency dramatically reduced the splicing efficiency of five cis-introns(nad5 intron 1;nad7 introns 1,2,and 3;and ccm Fc intron 1)and one trans-intron(nad2 intron 2),leading to lower levels of mitochondrial complexes I andⅢ.Zm RH48 interacts with two unique pentatricopeptide repeat(PPR)proteins,PPR-SMR1 and SPR2,which are required for the splicing of over half of all mitochondrial introns.PPR-SMR1 interacts with SPR2,and both proteins interact with P-type PPR proteins and Zm-m CSF1 to facilitate intron splicing.These results suggest that Zm RH48 is likely a component of a splicing complex and is critical for mitochondrial complex biosynthesis and seed development.展开更多
During adaptive radiation,mitochondria have co-evolved with their hosts,leading to gain or loss of subunits and assembly factors of respiratory complexes.Plant mitochondrial complex Ⅰ harbors40 nuclearand 9 mitochond...During adaptive radiation,mitochondria have co-evolved with their hosts,leading to gain or loss of subunits and assembly factors of respiratory complexes.Plant mitochondrial complex Ⅰ harbors40 nuclearand 9 mitochondrial-encoded subunits,and is formed by stepwise assembly during which different intermediates are integrated via various assembly factors.In mammals,the mitochondrial complex Ⅰ intermediate assembly(MCIA)complex is required for building the membrane arm module.However,plants have lost almost all of the MCIA complex components,giving rise to the hypothesis that plants follow an ancestral pathway to assemble the membrane arm subunits.Here,we characterize a maize crumpled seed mutant,crk1,and reveal by map-based cloning that CRK1 encodes an ortholog of human complex Ⅰ assembly factor 1,zNDUFAF1,the only evolutionarily conserved MCIA subunit in plants.zNDUFAF1 is localized in the mitochondria and accumulates in two intermediate complexes that contain complex Ⅰ membrane arm subunits.Disruption of zNDUFAF1 results in severe defects in complex Ⅰ assembly and activity,a cellular bioenergetic shift to aerobic glycolysis,and mitochondrial vacuolation.Moreover,we found that zNDUFAF1,the putative mitochondrial import inner membrane translocase ZmTIM17-1,and the isovaleryl-coenzyme A dehydrogenase ZmIVD1 interact each other,and could be co-precipitated from the mitochondria and co-migrate in the same assembly intermediates.Knockout of either ZmTIM17-1 or ZmIVD1 could lead to the significantly reduced complex Ⅰ stability and activity as well as defective seeds.These results suggest that zNDUFAF1,ZmTIM17-1 and ZmIVD1 probably form an MCIA-like complex that is essential for the biogenesis of mitochondrial complex Ⅰ and seed development in maize.Our findings also imply that plants and mammals recruit MCIA subunits independently for mitochondrial complex Ⅰ assembly,highlighting the importance of parallel evolution in mitochondria adaptation to their hosts.展开更多
Nuclear factor Y(NF-Y),a group of conserved transcription-factor complexes that consist of NF-YA,B,and C subunits,is essential for developmental regulation and for responses to environmental changes in eukaryotes.We p...Nuclear factor Y(NF-Y),a group of conserved transcription-factor complexes that consist of NF-YA,B,and C subunits,is essential for developmental regulation and for responses to environmental changes in eukaryotes.We previously found that some NF-Y genes,such as OsNF-YA8,were expressed specifically in the endosperm of rice.In the present study,overexpression of OsNF-YA8 in rice resulted in reduced plant height due to suppressed cell elongation in internodes.Gibberellin(GA)biosynthetic genes,including OsCPS1,OsGA20ox1,and OsGA20ox2,were down-regulated.OsNF-YA8 bound to the promoters of these genes to repress their expression.Endogenous GA content was decreased in OsNF-YA8 overexpressors,whose dwarf phenotype could be partially rescued by exogenous GA treatment.The findings suggested that ectopic expression of OsNF-YA8 causes defective GA biosynthesis in vegetative stage.Heading date in OsNF-YA8 overexpressors was delayed,especially under short-day conditions.OsNFYA8 bound to the promoter of Heading Date 3a(Hd3a),the florigen gene in rice,to negatively regulate flowering.Either ectopic activation or knockout of OsNF-YA8 impaired seed development,as indicated by reduced seed size and increased grain chalkiness.These results suggest that ectopic expression of the endosperm-specific OsNF-YA8 in rice disrupts both vegetative and reproductive development.展开更多
The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism ...The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism of RcWRI1 in regulating oil accumulation during seed development has not been clearly addressed.Castor bean(Ricinus communis)is one of the most important non-edible oil crops and its seed oils are rich in hydroxy fatty acids,widely applied in industry.In this study,based on castor bean reference genome,three RcWRIs genes(RcWRI1,RcWRI2 and RcWRI3)were identified and the expressed association of RcWRI1 with oil accumulation were determined.Heterologous transformation of RcWRI1 significantly increased oil content in tobacco leaf,confirming that RcWRI1 activate lipid biosynthesis pathway.Using DNA Affinity Purification sequencing(DAP-seq)technology,we confirmed RcWRI1 binding with Transcription Start Site of genes and identified 7961 WRI1-binding candidate genes.Functionally,these identified genes were mainly involved in diverse metabolism pathways(including lipid biosynthesis).Three cis-elements AW-box([CnTnG](n)7[CG])and AW-boxes like([GnAnC](n)6[GC]/[GnAnC](n)7[G])bound with RcWRI1 were identified.Co-expression network analysis of RcWRI1 further found that RcWRI1 might be widely involved in biosynthesis of storage materials during seed development.In particular,yeast one hybrid experiments found that both AP2 domains within RcWRI1 were required in binding targeted genes.These results not only provide new evidence to understand the regulatory mechanism of RcWRI1 in regulation of oil accumulation during castor bean seed development,but also give candidate gene resource for subsequent genetic improvement toward increasing oil content in oilseed crops.展开更多
Chinese agricultural industry and rural economy are currently undergoing a strategic restructuring. The Seed Act has been thoroughly enforced. The Development of West China program has also got started in an all-round...Chinese agricultural industry and rural economy are currently undergoing a strategic restructuring. The Seed Act has been thoroughly enforced. The Development of West China program has also got started in an all-round way. Not long ago China entered the World Trade Organization. All these not only present great opportunities but also severe challenges to China.展开更多
Herbaceous peony is a promising oilseed crop.‘Hangshao’and‘Fenghuang Niepan’are two cultivars with high yield and oil content In this study,seed reserved nutrient of these two genotypes were investigated during se...Herbaceous peony is a promising oilseed crop.‘Hangshao’and‘Fenghuang Niepan’are two cultivars with high yield and oil content In this study,seed reserved nutrient of these two genotypes were investigated during seed development process.Results showed that‘Hangshao’and‘Fenghuang Niepan’matured approximately 85 d after flowering(DAF).The development p rocess could be divided into four stages:seed formation and enlargement stage(S1),seed inclusion and enrichment stage(S2),crude fat rapid accumulation stage(S3)and dehydration and color transition stage(S4).During this process,100-seed fresh weight(HFW)and 100-seed dry weight(HDW)increased,whereas water content(WC)decreased.HFW,HDW and WC for‘Hangshao’seed at 85 DAF were28.56 g,20.78 g and 37.50%respectively,whereas those for‘Fenghuang Niepan’seed were 27.2 g,19.78 g,and30.85%respectively.In terms of the primary metabolites measuring,soluble protein content was consistently low(only 2.24%-3.15%),while starch content was relatively high(5.60%-24.81%).They displayed a trend of gradual increasing in early stage,followed by rapid decline.Crude fat tended to accumulate continuously with a linear upward trend starting at 40 DAF,and its maximum level was reached at 85 DAF(27.57%for‘Hangshao’and29.57%for‘Fenghuang Niepan’).For the secondary metabolites determination,total phenols content was relatively steady,maintaining at 107.7-129.9 mg/g for both cultivars,while total flavonoids content varied within25.33-65.33 mg/g for‘Hangshao’and 24.33-52.37 mg/g for Tenghuang Niepan’.The maximum level for both cultivars occurred at 55 DAF.Furthermore,crude fat content was found to be highly correlated with WC by correlation analysis and linear regression model definition(P≤0.01 and r=0.954).Thus,WC was recommended for evaluating crude fat in peony seed.These findings could provide scientific reference for high-yielding production practice for oleaginous peony plant.展开更多
基金supported by the Agricultural Science and Technology Innovation Program of CAASthe Research Program of Sanya Yazhou Bay Science and Technology City (SKJC-2020-02-005)the Natural Science Foundation of Jiangsu Province(BK20200288)。
文摘Although several pentatricopeptide repeat(PPR) proteins are involved in post-transcriptional processing of mitochondrial RNA, it is unclear which specific protein is involved in the RNA editing of ccmC in maize(Zea mays). Here we report the identification of the maize empty pericarp 601(emp601) mutant and the map-based cloning of the Emp601 gene, which encodes an E2-type PPR protein that is targeted to mitochondria. A single-nucleotide deletion in the emp601 mutant caused a frameshift and introduced a premature stop codon into the predicted EMP601. This mutation was associated with reduced accumulation of mitochondrial complex Ⅲ as well as with inhibition of growth and differentiation of basal endosperm transfer layer cells, leading to final degeneration of the embryo and endosperm. We determine that loss of EMP601 function prevents the C-to-U RNA editing of the mitochondrial transcript ccmC at position 358.EMP601 binds to the ccmC transcript and directly interacts with Multiple organellar RNA editing factor 8and may be a component of the plant mitochondrial editosome. We conclude that EMP601 functions in RNA editing of mitochondrial ccmC transcripts and influences mitochondrial function and seed development.
基金financially supported by the National Natural Science Foundation of China(Grant No.21777072)。
文摘Zinc(Zn) is an essential mineral element for plant growth and development. Zn deficiency in crops frequently occurs in many types of soils. It is therefore crucial to identify genetic resources linking Zn acquisition traits and development of crops with improved Zn-use efficiency for sustainable crop production. In this study, we functionally identified a rice uncharacterized ABCG(ATP-binding cassette G-subfamily) gene encoding a PDR20(pleiotropic drug resistance 20) metal transporter for mediation of rice growth, seed development and Zn accumulation. OsPDR20 was localized to the plasma membrane, but it was not transcriptionally induced under Zn deficiency, rather was sufficiently up-regulated under high level of Zn stress. Yeast(Saccharomyces cerevisiae) transformed with OsPDR20 displayed a relatively lower Zn accumulation with attenuated cellular growth, suggesting that OsPDR20 had an activity for Zn transport. Knocking-down OsPDR20 by RNA interference(RNAi) compromised rice growth with shorter plant height and decreased biomass in rice plantlets grown under hydroponic media. Zn concentration in the roots of OsPDR20 knocked-down rice lines declined under Zn deficiency, while they remained unchanged compared with the wild type under normal Zn supply. A rice lifelong field trial demonstrated that OsPDR20 mutation impaired the capacity of seed development, with shortened panicle and seed length, compromised spikelet fertility, and reduced grain number per plant or grain weight per unit area. Interestingly, OsPDR20 mutation elevated the accumulation of Zn in husk and brown rice over the wild type. Overall, this study pointed out that OsPDR20 is fundamentally required for rice growth and seed development through Zn transport and homeostasis.
基金supported by the National Youth Talent Program (A279021801)Key-Area R&D Program of Guangdong province (2022B0202060001)+4 种基金Key R&D Program of Shaanxi Province (2023-YBNY-008)the Science and Technology Innovation Team of Shaanxi (2021TD-32)the Natural Science Foundation of Shaanxi Province (2021JM-089, 2022JM-112 and 2022JQ-162)the Key R&D Project from Yangling Seed Industry Innovation Center (K3031322016)the Fundamental Research Fund from Northwest A&F University (2452022111)。
文摘The nuclear factor Y(NF-Y) gene family is a class of transcription factors that are widely distributed in eukaryotes and are involved in various biological processes. However, the NF-Y gene family members in watermelon, a valued and nutritious fruit, remain largely unknown and their functions have not been characterized. In the present study, 22 ClNF-Y genes in watermelon, 29 CsNF-Y genes in cucumber, and 24CmNF-Y genes in melon were identified based on the whole-genome investigation and their protein properties, gene location, gene structure, motif composition, conserved domain, and evolutionary relationship were investigated. ClNF-YB9 from watermelon and its homologs in cucumber and melon were expressed specifically in seeds. Its expression remained low in the early stages of watermelon seed development,increased at 20 days after pollination(DAP), and peaked at 45–50 DAP. Moreover, the knockout mutant Clnf-yb9 exhibited abnormal leafy cotyledon phenotype, implying its critical role during seed formation.Finally, protein interaction assays showed that ClNF-YB9 interacts with all ClNF-YCs and the ClNF-YB9-YC4 heterodimer was able to recruit a ClNF-YA7 subunit to assemble a complete NF-Y complex, which may function in seed development. This study revealed the structure and evolutionary relationships of the NF-Y gene family in Cucurbitaceae and the novel function of ClNF-YB9 in regulating seed development in watermelon.
基金the National Key Basic Research Development Program (Grant No. 2000018605 and 1999011708) the Major Research Plan of NSFC (Grant No. 90102012) and the Chinese National Outstanding Youth Fund (Grant No. 40025106)
文摘ABA is one of the 5 phytohormones in higher plants, which is also the most important hormone that regulates higher plants in response to environmental stress, by ABA signal transduction. Understanding ABA signal transduction at the molecular level is crucial to biology and ecology, and rational breeding complied with corresponding eco-environmental changes. Great advancements have taken place over the past 10 years by application of the Arabidopsis experimental system. Many components involved in ABA signal transduction have been isolated and identified and a clear overall picture of gene expression and control for this transduction has become an accepted fact. On the basis of the work in our laboratory, in conjunction with the data available at the moment, the authors have attempted to integrate ABA signal transduction pathways into a common one and give some insights into the relationship between ABA signal transduction and other hormone signal transduction pathways, with an emphasis upon the ABA signal transduction during higher plant seed development. A future challenge in this field is that different experimental systems are applied and various receptors and genes need to be characterized through the utilization of microarray chips.
基金National Natural Science Foundation of China(31661143002,81760507,31571709,31771839,31701123 and 31501034)Yunnan Applied Basic Research Projects(2016FA011,2016FB060 and 2016FB040)+1 种基金the National R&D Infrastructure and Facility development Program of China"Fundamental Science Data Sharing Platform(DKA 201712-02-16)the 13th Five-year informatization Plan of Chinese Academy of Sciences(No.XXH13506)。
文摘The B3 transcription factors(TFs)in plants play vital roles in numerous biological processes.Although B3 genes have been broadly identified in many plants,little is known about their potential functions in mediating seed development and material accumulation.Castor bean(Ricinus communis)is a non-edible oilseed crop considered an ideal model system for seed biology research.Here,we identified a total of 61 B3 genes in the castor bean genome,which can be classified into five subfamilies,including ABI3/VP1,HSI,ARF,RAV and REM.The expression profiles revealed that RcABI3/VP1 subfamily genes are significantly up-regulated in the middle and later stages of seed development,indicating that these genes may be associated with the accumulation of storage oils.Furthermore,through yeast one-hybrid and tobacco transient expression assays,we detected that ABI3/VP1 subfamily member RcLEC2 directly regulates the transcription of RcOleosin2,which encodes an oil-body structural protein.This finding suggests that RcLEC2,as a seed-specific TF,may be involved in the regulation of storage materials accumulation.This study provides novel insights into the potential roles and molecular basis of B3 family proteins in seed development and material accumulation.
基金the National Key Research and Development Program of China(2017YFD0300103)the National Natural Science Foundation of China(31771719)+1 种基金the National High Technology Research and Development Program of China(2014AA10A605)strategic funding from the Biotechnological and Biological Sciences Research Council of the UK.funding from the Designing Future Wheat Strategic Program(BB/P016855/1)。
文摘Interaction between the embryo and endosperm affects seed development,an essential process in yield formation in crops such as rice.Signals that mediate communication between embryo and endosperm are largely unknown.We used the notched-belly(NB)mutant with impaired communication between embryo and endosperm to investigate the effect of the embryo on developmental staging of the endosperm and signaling pathways in the embryo that regulate endosperm development.Hierachical clustering of m RNA datasets from embryo and endosperm samples collected during development in NB and a wild type showed a delaying effect of the embryo on the developmental transition of the endosperm by extension of the middle stage.K-means clustering further identified coexpression modules of gene sets specific to embryo and endosperm development.Combined gene expression and biochemical analysis showed that T6 P–Sn RK1,gibberellin and auxin signaling by the embryo regulate endosperm developmental transition.We propose a new seed developmental staging system for rice and identify the most detailed signature of rice grain formation to date.These will direct genetic strategies for rice yield improvement.
基金supported by the National Natural Science Foundation of China (Project Nos.32072126 and 32230075)the Shandong Provincial Natural Science Foundation (Project No.ZR2019MC005)。
文摘RNA helicases participate in nearly all aspects of RNA metabolism by rearranging RNAs or RNA–protein complexes in an adenosine triphosphatedependent manner.Due to the large RNA helicase families in plants,the precise roles of many RNA helicases in plant physiology and development remain to be clarified.Here,we show that mutations in maize(Zea mays)DEAD-box RNA helicase48(Zm RH48)impair the splicing of mitochondrial introns,mitochondrial complex biosynthesis,and seed development.Loss of Zm RH48 function severely arrested embryogenesis and endosperm development,leading to defective kernel formation.Zm RH48 is targeted to mitochondria,where its deficiency dramatically reduced the splicing efficiency of five cis-introns(nad5 intron 1;nad7 introns 1,2,and 3;and ccm Fc intron 1)and one trans-intron(nad2 intron 2),leading to lower levels of mitochondrial complexes I andⅢ.Zm RH48 interacts with two unique pentatricopeptide repeat(PPR)proteins,PPR-SMR1 and SPR2,which are required for the splicing of over half of all mitochondrial introns.PPR-SMR1 interacts with SPR2,and both proteins interact with P-type PPR proteins and Zm-m CSF1 to facilitate intron splicing.These results suggest that Zm RH48 is likely a component of a splicing complex and is critical for mitochondrial complex biosynthesis and seed development.
基金supported by a grant from the Ministry of Science and Technology of the People’s Republic of China 2021YFF1000303(to Guifeng Wang)grants from the National Natural Science Foundation of China(U1804235 to Guifeng Wang,32001562 to Q.S.).
文摘During adaptive radiation,mitochondria have co-evolved with their hosts,leading to gain or loss of subunits and assembly factors of respiratory complexes.Plant mitochondrial complex Ⅰ harbors40 nuclearand 9 mitochondrial-encoded subunits,and is formed by stepwise assembly during which different intermediates are integrated via various assembly factors.In mammals,the mitochondrial complex Ⅰ intermediate assembly(MCIA)complex is required for building the membrane arm module.However,plants have lost almost all of the MCIA complex components,giving rise to the hypothesis that plants follow an ancestral pathway to assemble the membrane arm subunits.Here,we characterize a maize crumpled seed mutant,crk1,and reveal by map-based cloning that CRK1 encodes an ortholog of human complex Ⅰ assembly factor 1,zNDUFAF1,the only evolutionarily conserved MCIA subunit in plants.zNDUFAF1 is localized in the mitochondria and accumulates in two intermediate complexes that contain complex Ⅰ membrane arm subunits.Disruption of zNDUFAF1 results in severe defects in complex Ⅰ assembly and activity,a cellular bioenergetic shift to aerobic glycolysis,and mitochondrial vacuolation.Moreover,we found that zNDUFAF1,the putative mitochondrial import inner membrane translocase ZmTIM17-1,and the isovaleryl-coenzyme A dehydrogenase ZmIVD1 interact each other,and could be co-precipitated from the mitochondria and co-migrate in the same assembly intermediates.Knockout of either ZmTIM17-1 or ZmIVD1 could lead to the significantly reduced complex Ⅰ stability and activity as well as defective seeds.These results suggest that zNDUFAF1,ZmTIM17-1 and ZmIVD1 probably form an MCIA-like complex that is essential for the biogenesis of mitochondrial complex Ⅰ and seed development in maize.Our findings also imply that plants and mammals recruit MCIA subunits independently for mitochondrial complex Ⅰ assembly,highlighting the importance of parallel evolution in mitochondria adaptation to their hosts.
基金the National Natural Science Foundation of China(31701392 and 32170344)the Six Talent Peaks Project in Jiangsu Province(NY-142)+1 种基金the Jiangsu Province Government(JBGS[2021]001)the Independent Scientific Research Project Funds of the Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding(PLR202101).
文摘Nuclear factor Y(NF-Y),a group of conserved transcription-factor complexes that consist of NF-YA,B,and C subunits,is essential for developmental regulation and for responses to environmental changes in eukaryotes.We previously found that some NF-Y genes,such as OsNF-YA8,were expressed specifically in the endosperm of rice.In the present study,overexpression of OsNF-YA8 in rice resulted in reduced plant height due to suppressed cell elongation in internodes.Gibberellin(GA)biosynthetic genes,including OsCPS1,OsGA20ox1,and OsGA20ox2,were down-regulated.OsNF-YA8 bound to the promoters of these genes to repress their expression.Endogenous GA content was decreased in OsNF-YA8 overexpressors,whose dwarf phenotype could be partially rescued by exogenous GA treatment.The findings suggested that ectopic expression of OsNF-YA8 causes defective GA biosynthesis in vegetative stage.Heading date in OsNF-YA8 overexpressors was delayed,especially under short-day conditions.OsNFYA8 bound to the promoter of Heading Date 3a(Hd3a),the florigen gene in rice,to negatively regulate flowering.Either ectopic activation or knockout of OsNF-YA8 impaired seed development,as indicated by reduced seed size and increased grain chalkiness.These results suggest that ectopic expression of the endosperm-specific OsNF-YA8 in rice disrupts both vegetative and reproductive development.
基金This work was supported by National Natural Science Foundation of China(grant number 31701465)。
文摘The transcription factor WRINKLED1(WRI1),a member of AP2 gene family that contain typical AP2 domains,has been considered as a master regulator regulating oil biosynthesis in oilseeds.However,the regulatory mechanism of RcWRI1 in regulating oil accumulation during seed development has not been clearly addressed.Castor bean(Ricinus communis)is one of the most important non-edible oil crops and its seed oils are rich in hydroxy fatty acids,widely applied in industry.In this study,based on castor bean reference genome,three RcWRIs genes(RcWRI1,RcWRI2 and RcWRI3)were identified and the expressed association of RcWRI1 with oil accumulation were determined.Heterologous transformation of RcWRI1 significantly increased oil content in tobacco leaf,confirming that RcWRI1 activate lipid biosynthesis pathway.Using DNA Affinity Purification sequencing(DAP-seq)technology,we confirmed RcWRI1 binding with Transcription Start Site of genes and identified 7961 WRI1-binding candidate genes.Functionally,these identified genes were mainly involved in diverse metabolism pathways(including lipid biosynthesis).Three cis-elements AW-box([CnTnG](n)7[CG])and AW-boxes like([GnAnC](n)6[GC]/[GnAnC](n)7[G])bound with RcWRI1 were identified.Co-expression network analysis of RcWRI1 further found that RcWRI1 might be widely involved in biosynthesis of storage materials during seed development.In particular,yeast one hybrid experiments found that both AP2 domains within RcWRI1 were required in binding targeted genes.These results not only provide new evidence to understand the regulatory mechanism of RcWRI1 in regulation of oil accumulation during castor bean seed development,but also give candidate gene resource for subsequent genetic improvement toward increasing oil content in oilseed crops.
文摘Chinese agricultural industry and rural economy are currently undergoing a strategic restructuring. The Seed Act has been thoroughly enforced. The Development of West China program has also got started in an all-round way. Not long ago China entered the World Trade Organization. All these not only present great opportunities but also severe challenges to China.
基金financially supported by the Agricultural Major Applied Technology Innovation Project of Shandong ProvinceChina(No.2016-36)。
文摘Herbaceous peony is a promising oilseed crop.‘Hangshao’and‘Fenghuang Niepan’are two cultivars with high yield and oil content In this study,seed reserved nutrient of these two genotypes were investigated during seed development process.Results showed that‘Hangshao’and‘Fenghuang Niepan’matured approximately 85 d after flowering(DAF).The development p rocess could be divided into four stages:seed formation and enlargement stage(S1),seed inclusion and enrichment stage(S2),crude fat rapid accumulation stage(S3)and dehydration and color transition stage(S4).During this process,100-seed fresh weight(HFW)and 100-seed dry weight(HDW)increased,whereas water content(WC)decreased.HFW,HDW and WC for‘Hangshao’seed at 85 DAF were28.56 g,20.78 g and 37.50%respectively,whereas those for‘Fenghuang Niepan’seed were 27.2 g,19.78 g,and30.85%respectively.In terms of the primary metabolites measuring,soluble protein content was consistently low(only 2.24%-3.15%),while starch content was relatively high(5.60%-24.81%).They displayed a trend of gradual increasing in early stage,followed by rapid decline.Crude fat tended to accumulate continuously with a linear upward trend starting at 40 DAF,and its maximum level was reached at 85 DAF(27.57%for‘Hangshao’and29.57%for‘Fenghuang Niepan’).For the secondary metabolites determination,total phenols content was relatively steady,maintaining at 107.7-129.9 mg/g for both cultivars,while total flavonoids content varied within25.33-65.33 mg/g for‘Hangshao’and 24.33-52.37 mg/g for Tenghuang Niepan’.The maximum level for both cultivars occurred at 55 DAF.Furthermore,crude fat content was found to be highly correlated with WC by correlation analysis and linear regression model definition(P≤0.01 and r=0.954).Thus,WC was recommended for evaluating crude fat in peony seed.These findings could provide scientific reference for high-yielding production practice for oleaginous peony plant.
