A key physics issue for achieving steady-state high-performance plasmas on EAST tokamak is to decrease beam-ion losses to improve plasma confinement during neutral beam injections(NBIs).To decrease the beam losses,pre...A key physics issue for achieving steady-state high-performance plasmas on EAST tokamak is to decrease beam-ion losses to improve plasma confinement during neutral beam injections(NBIs).To decrease the beam losses,previous counter-I_(p)NBI injections are upgraded to co-I_(p)injections.Analysis shows that due to the reversed direction of drift across the flux surfaces caused by the pitch angle,the beam prompt loss fraction decreases from about 49%to 3%after the upgrade.Moreover,because of the change of entire beam path,beam shine-through(ST)loss fraction for counter-I_(p)tangential and counter-I_(p)perpendicular injections is reversed to co-I_(p)tangential and co-I_(p)perpendicular injections,respectively.Due to the change in the initial trapped-confined beam ion fraction caused by the peaked pitch profiles,the losses induced by toroidal ripple field are also reversed after the upgrade.To further improve the beam-ion confinement under the present NBI layout,the amplitudes of toroidal field are increased from 1.75 to 2.20 T.Result shows that,due to the smaller orbit width and peaked pitch angle profile,the beam prompt loss power is lower with higher toroidal field.Due to the synergy of higher initial trapped-confined beam ion fraction and narrower Goldston-White-Boozer(GWB)boundary,the loss induced by ripple diffusion is higher with higher toroidal field.The combined effect of beam ST loss,prompt loss and ripple loss,contributes to the increase in beam ion density.The decrease in beam loss power enhances beam heating efficiency,especially the fraction of beam heating ions.Finally,comparison between simulation and measurement by^(235)U fission chamber(FC)indicates that the increase in neutron rate is mainly contributed by improvement of beam-ion confinement.This study can provide potential support for beam operation and high-T_(i)experiment on EAST tokamak.展开更多
Abscisic acid(ABA)is a critical regulator of seed development and germination.β-glucosidases(BGs)have been suggested to be contributors to increased ABA content because they catalyze the hydrolysis of ABA-glucose est...Abscisic acid(ABA)is a critical regulator of seed development and germination.β-glucosidases(BGs)have been suggested to be contributors to increased ABA content because they catalyze the hydrolysis of ABA-glucose ester to release free ABA.However,whether BGs are involved in seed development is unclear.In this study,a candidate gene,CiBG1,in watermelon was selected for targeted mutagenesis via the CRISPR/Cas9 system.Seed size and weight were significantly reduced in the Clbg1-mutant watermelon lines,which was mainly attributed to decreased cell number resulting from decreased ABA levels.A transcriptome analysis showed that the expression of 1015 and 1429 unique genes was changed 10 and 18 days after pollination(DAP),respectively.Cytoskeleton-and cell cycle-related genes were enriched in the differentially expressed genes of wild type and Clbg1-mutant lines during seed development.Moreover,the expression of genes in the major signaling pathways of seed size control was also changed.In addition,seed germination was promoted in the Cibg1-mutant lines due to decreased ABA content.These results indicate that ClBG1 may be critical for watermelon seed size regulation and germination mainly through the modulation of ABA content and thereby the transcriptional regulation of cytoskeleton-,cell cycle-and signaling-related genes.Our results lay a foundation for dissecting the molecular mechanisms of controlling watermelon seed size,a key agricultural trait of significant economic importance.展开更多
In this article 1,author name Yanping Wang was incorrectly tagged as corresponding author.Prof.Wang should be the co-first author,instead of the corresponding author.The original article has been corrected.
NAC(NAM,ATAF1/2,and CUC2)transcription factors play important roles in fruit ripening and quality.The watermelon genome encodes 80 NAC genes,and 21 of these NAC genes are highly expressed in both the flesh and vascula...NAC(NAM,ATAF1/2,and CUC2)transcription factors play important roles in fruit ripening and quality.The watermelon genome encodes 80 NAC genes,and 21 of these NAC genes are highly expressed in both the flesh and vascular tissues.Among these genes,CINAC68 expression was signi fi cantly higher in flesh than in rind.However,the intrinsic regulatory mechanism of CINAC68 in fruit ripening and quality is still unknown.In this study,we found that ClNAC68 is a transcriptional repressor and that the repression domain is located in the C-terminus.Knockout of CINAC68 by the CRISPR-Cas9 system decreased the soluble solid content and sucrose accumulation in mutant flesh.Development was delayed,germination was inhibited,and the IAA content was signi ficantly decreased in mutant seeds.Transcriptome analysis showed that the invertase gene CUNV was the only gene involved in sucrose metabolism that was upregulated in mutant flesh,and expression of the indole-3-acetic acid-amido synthetase gene CIGH3.6 in the IAA signaling pathway was also induced in mutant seeds.EMSA and dual-luciferase assays showed that CINAC68 directly bound to the promoters of CUNV and CIGH3.6 to repress their expression.These results indicated that CINAC68 positively regulated sugar and IAA accumulation by repressing CUNV and CIGH3.6.Our findings provide new insights into the regulatory mechanisms by which NAC transcription factors affect fruit quality and seed development.展开更多
2D fast-ion velocity-space distributions have been reconstructed from two-view fast-ion D-alpha(FIDA)measurements on experimental advanced superconducting tokamak(EAST).To make up for the sparse data and incomplete ve...2D fast-ion velocity-space distributions have been reconstructed from two-view fast-ion D-alpha(FIDA)measurements on experimental advanced superconducting tokamak(EAST).To make up for the sparse data and incomplete velocity-space coverage with the dual-view,we use nonnegativity and null-measurements as prior information to reconstruct the velocity distribution in experiments with co-and counter-current neutral beam injection.An improved reconstructed fast-ion distribution is achieved by combining the existing O-and B-port FIDA measurements with the proposed A-port FIDA view.To further improve the reliability of FIDA-based reconstructions on EAST,based on real multi-view FIDA measurements on EAST in the near future,various bases will be studied further.展开更多
The absorption of neutral beam power and the fast ion stored energy in EAST plasmas with neutral beam injection(NBI)is analyzed to improve the calculation of thermal energy confinement time.The neutral beam power abso...The absorption of neutral beam power and the fast ion stored energy in EAST plasmas with neutral beam injection(NBI)is analyzed to improve the calculation of thermal energy confinement time.The neutral beam power absorption and fast ion stored energy are systematically calculated using the TRANSP code,through the investigation of global parameters including plasma current,line averaged density and beam energy.Results have shown that scaling laws for the NBI absorption coefficient and fast ion energy rate are obtained through statistical analysis.A comparison of the confinement improvement factor H98y2 with these new scaling laws against those assuming fixed coefficients is given.展开更多
1.Background Engel's biopsychosocial model,which was constructed in 1977,was considered a momentous breakthrough from the traditional biomedical model of medicine that regards the person as a disease-carrier requi...1.Background Engel's biopsychosocial model,which was constructed in 1977,was considered a momentous breakthrough from the traditional biomedical model of medicine that regards the person as a disease-carrier requiring diagnosis and treatment[1]towards recognition of the whole person and furnish customized care.This model argues that health should not be considered solely on biological factors but on a combination of biological,psychological,and social factors[2].This idea of considering individuals as a whole and respecting their rights to self-determination has led to a shift in the care model from disease-centered care to patient-centered or person-centered care.The latter two care models are both abbreviated as PCC.Ensuring that people are involved in and central to the healthcare process is now recognized as a key component in developing high-quality care.Studies have revealed that both concepts of care can help improve people's health condition and lower health service burdens.Thus,countries and healthcare organizations have been paying close attention to the patients'concerns.The National Health Service in England has made person-centered care as one of its seven core principles[3].展开更多
Watermelon(Citrullus lanatus) as non-climacteric fruit is domesticated from the ancestors with inedible fruits. We previously revealed that the abscisic acid(ABA) signaling pathway gene ClSnRK2.3 might infuence waterm...Watermelon(Citrullus lanatus) as non-climacteric fruit is domesticated from the ancestors with inedible fruits. We previously revealed that the abscisic acid(ABA) signaling pathway gene ClSnRK2.3 might infuence watermelon fruit ripening. However,the molecular mechanisms are unclear. Here,we found that the selective variation of ClSnRK2.3 resulted in lower promoter activity and gene expression level in cultivated watermelons than ancestors, which indicated ClSnRK2.3 might be a negative regulator in fruit ripening. Overexpression (OE) of ClSnRK2.3 significantly delayed watermelon fruit ripening and suppressed the accumulation of sucrose, ABA and gibberellin GA4. Furthermore,we determined that the pyrophosphate-dependent phosphofructokinase(ClPFP1) in sugar metabolism pathway and GA biosynthesis enzyme GA20 oxidase(Cl GA20ox) could be phosphorylated by ClSnRK2.3 and thereby resulting in accelerated protein degradation in OE lines and finally led to low levels of sucrose and GA4. Besides that, ClSnRK2.3 phosphorylated homeodomain-leucine zipper protein(ClHAT1) and protected it from degradation to suppress the expression of the ABA biosynthesis gene 9’-cis-epoxycarotenoid dioxygenase 3(Cl NCED3). These results indicated that ClSnRK2.3 negatively regulated watermelon fruit ripening by manipulating the biosynthesis of sucrose, ABA and GA4. Altogether, these findings revealed a novel regulatory mechanism in non-climacteric fruit development and ripening.展开更多
A resonator fiber optic gyro with the light time-division input and multiplexing output(TDM-RFOG)in the clockwise(CW)and counterclockwise(CCW)directions is proposed.The light time-division input in the CW and CCW dire...A resonator fiber optic gyro with the light time-division input and multiplexing output(TDM-RFOG)in the clockwise(CW)and counterclockwise(CCW)directions is proposed.The light time-division input in the CW and CCW directions can effectively suppress the backscattering induced noise.The TDM-RFOG is implemented with the 2×2 Mach–Zehnder interferometer(MZI)optical switch.The response time of the fiber ring resonator is analyzed,and it is demonstrated by experiments that light time-division input in the CW and CCW directions can reduce the backscattering induced noise.The suppression effectiveness of backscattering induced noise in the TDM-RFOG is determined by the extinction ratio of the optical switch,so a closed loop is designed to adjust the phase shift difference between the two arms of the MZI optical switch to control the extinction ratio.The method using two arms of the MZI optical switch with twin 90°polarization-axis rotated splices is proposed to make the extinction ratio along both slow and fast axes greater than-70 d B.展开更多
ThThe NAC transcription factor NONRIPENING(NOR)is a master regulator of climacteric fruit ripening.Melon(Cucumis melo L.)has climacteric and nonclimacteric fruit ripening varieties and is an ideal model to study fruit...ThThe NAC transcription factor NONRIPENING(NOR)is a master regulator of climacteric fruit ripening.Melon(Cucumis melo L.)has climacteric and nonclimacteric fruit ripening varieties and is an ideal model to study fruit ripening.Two natural CmNAC-NOR variants,the climacteric haplotype CmNAC-NOR^(S,N) and the non-climacteric haplotype CmNAC-NOR^(A,S),have effects on fruit ripening;however,their regulatory mechanisms have not been elucidated.Here,we report that a natural mutation in the transcriptional activation domain of CmNAC-NORS,Ncontributes to climacteric melon fruit ripening.CmNAC-NOR knockout in the climacteric-type melon cultivar“BYJH”completely inhibited fruit ripening,while ripening was delayed by 5-8 d in heterozygous cmnac-nor mutant fruits.CmN AC-NOR directly activated carotenoid,ethylene,and abscisic acid biosynthetic genes to promote fruit coloration and ripening.Furthermore,CmNAC-NOR mediated the transcription of the“CmNAC-NOR-CmNAC73-CmCWINV2”module to enhance flesh sweetness.The transcriptional activation activity of the climacteric haplotype CmNAC-NORS,Non these target genes was significantly higher than that of the nonclimacteric haplotype CmNAC-NOR^(A,S).Moreover,CmNAC-NORS,Ncomplementation fully rescued the non-ripening phenotype of the tomato(Solanum lycopersicum)cr-nor mutant,while CmNAC-NOR^(A,S) did not.Our results provide insight into the molecular mechanism of climacteric and non-climacteric fruit ripening in melon.展开更多
Dear Editor, Brassica rapa is an important crop and a model plant for studying Brassica genome evolution and gene function. The silique of B. rapa derived from the gynoecium nor- mally consists of two carpels that ar...Dear Editor, Brassica rapa is an important crop and a model plant for studying Brassica genome evolution and gene function. The silique of B. rapa derived from the gynoecium nor- mally consists of two carpels that are separated by a false septum, and thus has two Iocules （bilocular）. Multilocular （more than two carpels） lines of B. rapa have been discov- ered in nature and are considered advantageous because the multilocular type could potentially increase the seed yield by producing more seeds per silique than the biloc- ular type. However, the molecular basis of the important seed vield-related trait is ooorlv understood.展开更多
基金supported by the National Key R&D Program of China(No.2019YFE03020004)National Natural Science Foundation of China(Nos.12175272 and 12347186)+3 种基金Anhui Provincial Natural Science Foundation(No.2008085J04)Anhui Provincial Key R&D Program(No.202104b11020003)Collaborative Innovation Program of Hefei Science Center,CAS(No.YZJJ2023QN17)State Key Laboratory of Advanced Electromagnetic Technology(No.AET 2024KF010)。
文摘A key physics issue for achieving steady-state high-performance plasmas on EAST tokamak is to decrease beam-ion losses to improve plasma confinement during neutral beam injections(NBIs).To decrease the beam losses,previous counter-I_(p)NBI injections are upgraded to co-I_(p)injections.Analysis shows that due to the reversed direction of drift across the flux surfaces caused by the pitch angle,the beam prompt loss fraction decreases from about 49%to 3%after the upgrade.Moreover,because of the change of entire beam path,beam shine-through(ST)loss fraction for counter-I_(p)tangential and counter-I_(p)perpendicular injections is reversed to co-I_(p)tangential and co-I_(p)perpendicular injections,respectively.Due to the change in the initial trapped-confined beam ion fraction caused by the peaked pitch profiles,the losses induced by toroidal ripple field are also reversed after the upgrade.To further improve the beam-ion confinement under the present NBI layout,the amplitudes of toroidal field are increased from 1.75 to 2.20 T.Result shows that,due to the smaller orbit width and peaked pitch angle profile,the beam prompt loss power is lower with higher toroidal field.Due to the synergy of higher initial trapped-confined beam ion fraction and narrower Goldston-White-Boozer(GWB)boundary,the loss induced by ripple diffusion is higher with higher toroidal field.The combined effect of beam ST loss,prompt loss and ripple loss,contributes to the increase in beam ion density.The decrease in beam loss power enhances beam heating efficiency,especially the fraction of beam heating ions.Finally,comparison between simulation and measurement by^(235)U fission chamber(FC)indicates that the increase in neutron rate is mainly contributed by improvement of beam-ion confinement.This study can provide potential support for beam operation and high-T_(i)experiment on EAST tokamak.
基金supported by the National Natural Science Foundation of China(NSFC Grant Nos.31701938,31930096,and 1902034)Collaborative Innovation Center of BAAFS(KJCX201907-2)+2 种基金Ministry of Agriculture and Rural Affairs of China(Grant No.CARS-25)Beijing Scholar Program(Grant No.BSP026)Guanxi Bagui Scholar Program(Grant No.2016A11).
文摘Abscisic acid(ABA)is a critical regulator of seed development and germination.β-glucosidases(BGs)have been suggested to be contributors to increased ABA content because they catalyze the hydrolysis of ABA-glucose ester to release free ABA.However,whether BGs are involved in seed development is unclear.In this study,a candidate gene,CiBG1,in watermelon was selected for targeted mutagenesis via the CRISPR/Cas9 system.Seed size and weight were significantly reduced in the Clbg1-mutant watermelon lines,which was mainly attributed to decreased cell number resulting from decreased ABA levels.A transcriptome analysis showed that the expression of 1015 and 1429 unique genes was changed 10 and 18 days after pollination(DAP),respectively.Cytoskeleton-and cell cycle-related genes were enriched in the differentially expressed genes of wild type and Clbg1-mutant lines during seed development.Moreover,the expression of genes in the major signaling pathways of seed size control was also changed.In addition,seed germination was promoted in the Cibg1-mutant lines due to decreased ABA content.These results indicate that ClBG1 may be critical for watermelon seed size regulation and germination mainly through the modulation of ABA content and thereby the transcriptional regulation of cytoskeleton-,cell cycle-and signaling-related genes.Our results lay a foundation for dissecting the molecular mechanisms of controlling watermelon seed size,a key agricultural trait of significant economic importance.
文摘In this article 1,author name Yanping Wang was incorrectly tagged as corresponding author.Prof.Wang should be the co-first author,instead of the corresponding author.The original article has been corrected.
基金This work was financially supported by the Collaborative Innovation Center of BAAFS(KJCX201907-2)Beijing Science&Technology Program(D171100007617001)+3 种基金National Key R&D Program of China(2018YFD0100703)National Natural Science Foun dation of China(31930096 and 1902034)Beijing Natural Science Foundation(6204038 and 6202010)Beijing Scholar Program(BSP026 and YBSP019).
文摘NAC(NAM,ATAF1/2,and CUC2)transcription factors play important roles in fruit ripening and quality.The watermelon genome encodes 80 NAC genes,and 21 of these NAC genes are highly expressed in both the flesh and vascular tissues.Among these genes,CINAC68 expression was signi fi cantly higher in flesh than in rind.However,the intrinsic regulatory mechanism of CINAC68 in fruit ripening and quality is still unknown.In this study,we found that ClNAC68 is a transcriptional repressor and that the repression domain is located in the C-terminus.Knockout of CINAC68 by the CRISPR-Cas9 system decreased the soluble solid content and sucrose accumulation in mutant flesh.Development was delayed,germination was inhibited,and the IAA content was signi ficantly decreased in mutant seeds.Transcriptome analysis showed that the invertase gene CUNV was the only gene involved in sucrose metabolism that was upregulated in mutant flesh,and expression of the indole-3-acetic acid-amido synthetase gene CIGH3.6 in the IAA signaling pathway was also induced in mutant seeds.EMSA and dual-luciferase assays showed that CINAC68 directly bound to the promoters of CUNV and CIGH3.6 to repress their expression.These results indicated that CINAC68 positively regulated sugar and IAA accumulation by repressing CUNV and CIGH3.6.Our findings provide new insights into the regulatory mechanisms by which NAC transcription factors affect fruit quality and seed development.
基金supported by National Natural Science Foundation of China(No.11975276)Anhui Provincial Natural Science Foundation(No.2008085J04)+3 种基金Anhui Provincial Key R&D Programmes(No.202104b11020003)the National Key Research and Development Program of China(No.2019YFE03020004)the Excellence Program of Hefei Science Center CAS(No.2021HSC-UE015)。
文摘2D fast-ion velocity-space distributions have been reconstructed from two-view fast-ion D-alpha(FIDA)measurements on experimental advanced superconducting tokamak(EAST).To make up for the sparse data and incomplete velocity-space coverage with the dual-view,we use nonnegativity and null-measurements as prior information to reconstruct the velocity distribution in experiments with co-and counter-current neutral beam injection.An improved reconstructed fast-ion distribution is achieved by combining the existing O-and B-port FIDA measurements with the proposed A-port FIDA view.To further improve the reliability of FIDA-based reconstructions on EAST,based on real multi-view FIDA measurements on EAST in the near future,various bases will be studied further.
基金Numerical computations were performed on the ShenMa High Performance Computing Cluster in Institute of Plasma Physics,Chinese Academy of SciencesThe work is supported by National MCF Energy R&D Program of China(Nos.2018YFE0302100,2017YFE0301100)+1 种基金National Natural Science Foundation of China(Nos.11775262,11975274,11805237,11705239)the National Magnetic Confinement Fusion Science Program of China(No.2015GB102000).
文摘The absorption of neutral beam power and the fast ion stored energy in EAST plasmas with neutral beam injection(NBI)is analyzed to improve the calculation of thermal energy confinement time.The neutral beam power absorption and fast ion stored energy are systematically calculated using the TRANSP code,through the investigation of global parameters including plasma current,line averaged density and beam energy.Results have shown that scaling laws for the NBI absorption coefficient and fast ion energy rate are obtained through statistical analysis.A comparison of the confinement improvement factor H98y2 with these new scaling laws against those assuming fixed coefficients is given.
文摘1.Background Engel's biopsychosocial model,which was constructed in 1977,was considered a momentous breakthrough from the traditional biomedical model of medicine that regards the person as a disease-carrier requiring diagnosis and treatment[1]towards recognition of the whole person and furnish customized care.This model argues that health should not be considered solely on biological factors but on a combination of biological,psychological,and social factors[2].This idea of considering individuals as a whole and respecting their rights to self-determination has led to a shift in the care model from disease-centered care to patient-centered or person-centered care.The latter two care models are both abbreviated as PCC.Ensuring that people are involved in and central to the healthcare process is now recognized as a key component in developing high-quality care.Studies have revealed that both concepts of care can help improve people's health condition and lower health service burdens.Thus,countries and healthcare organizations have been paying close attention to the patients'concerns.The National Health Service in England has made person-centered care as one of its seven core principles[3].
基金financially supported by the National Natural Science Foundation of China (31930096, 31902034, 32172592, 32122077, and 32072601)Foundation of Beijing Academy of Agricultural and Forestry Sciences (QNJJ202032 and QNJJ202206)+4 种基金the Ministry of Agriculture and Rural Affairs of China (CARS-25)the Beijing Scholar Program (YBSP019)Foundation of Xinjiang production and construction corps (2022AB015)The Agriculture Innovation Consortium (BAIC04-2023)The Scientist Training Program of BAAFS (JKZX202211)。
文摘Watermelon(Citrullus lanatus) as non-climacteric fruit is domesticated from the ancestors with inedible fruits. We previously revealed that the abscisic acid(ABA) signaling pathway gene ClSnRK2.3 might infuence watermelon fruit ripening. However,the molecular mechanisms are unclear. Here,we found that the selective variation of ClSnRK2.3 resulted in lower promoter activity and gene expression level in cultivated watermelons than ancestors, which indicated ClSnRK2.3 might be a negative regulator in fruit ripening. Overexpression (OE) of ClSnRK2.3 significantly delayed watermelon fruit ripening and suppressed the accumulation of sucrose, ABA and gibberellin GA4. Furthermore,we determined that the pyrophosphate-dependent phosphofructokinase(ClPFP1) in sugar metabolism pathway and GA biosynthesis enzyme GA20 oxidase(Cl GA20ox) could be phosphorylated by ClSnRK2.3 and thereby resulting in accelerated protein degradation in OE lines and finally led to low levels of sucrose and GA4. Besides that, ClSnRK2.3 phosphorylated homeodomain-leucine zipper protein(ClHAT1) and protected it from degradation to suppress the expression of the ABA biosynthesis gene 9’-cis-epoxycarotenoid dioxygenase 3(Cl NCED3). These results indicated that ClSnRK2.3 negatively regulated watermelon fruit ripening by manipulating the biosynthesis of sucrose, ABA and GA4. Altogether, these findings revealed a novel regulatory mechanism in non-climacteric fruit development and ripening.
基金supported by the Shanghai Aerospace Science and Technology Innovation Fund(No.SAST2015076)。
文摘A resonator fiber optic gyro with the light time-division input and multiplexing output(TDM-RFOG)in the clockwise(CW)and counterclockwise(CCW)directions is proposed.The light time-division input in the CW and CCW directions can effectively suppress the backscattering induced noise.The TDM-RFOG is implemented with the 2×2 Mach–Zehnder interferometer(MZI)optical switch.The response time of the fiber ring resonator is analyzed,and it is demonstrated by experiments that light time-division input in the CW and CCW directions can reduce the backscattering induced noise.The suppression effectiveness of backscattering induced noise in the TDM-RFOG is determined by the extinction ratio of the optical switch,so a closed loop is designed to adjust the phase shift difference between the two arms of the MZI optical switch to control the extinction ratio.The method using two arms of the MZI optical switch with twin 90°polarization-axis rotated splices is proposed to make the extinction ratio along both slow and fast axes greater than-70 d B.
基金financially supported by Beijing Academy of Agricultural and Forestry Sciences(KJCX20200204)the National Natural Science Foundation of China(1902034,32122077,and 32172592)+3 种基金the Beijing Scholar Program(YBSP019)the Sci&Tech Innovation of BAAFS(KJCX20200113)the Agriculture Innovation Consortium(BAIC10-2022)the Key Project of Science and Technology of Ningbo(2019B10007)。
文摘ThThe NAC transcription factor NONRIPENING(NOR)is a master regulator of climacteric fruit ripening.Melon(Cucumis melo L.)has climacteric and nonclimacteric fruit ripening varieties and is an ideal model to study fruit ripening.Two natural CmNAC-NOR variants,the climacteric haplotype CmNAC-NOR^(S,N) and the non-climacteric haplotype CmNAC-NOR^(A,S),have effects on fruit ripening;however,their regulatory mechanisms have not been elucidated.Here,we report that a natural mutation in the transcriptional activation domain of CmNAC-NORS,Ncontributes to climacteric melon fruit ripening.CmNAC-NOR knockout in the climacteric-type melon cultivar“BYJH”completely inhibited fruit ripening,while ripening was delayed by 5-8 d in heterozygous cmnac-nor mutant fruits.CmN AC-NOR directly activated carotenoid,ethylene,and abscisic acid biosynthetic genes to promote fruit coloration and ripening.Furthermore,CmNAC-NOR mediated the transcription of the“CmNAC-NOR-CmNAC73-CmCWINV2”module to enhance flesh sweetness.The transcriptional activation activity of the climacteric haplotype CmNAC-NORS,Non these target genes was significantly higher than that of the nonclimacteric haplotype CmNAC-NOR^(A,S).Moreover,CmNAC-NORS,Ncomplementation fully rescued the non-ripening phenotype of the tomato(Solanum lycopersicum)cr-nor mutant,while CmNAC-NOR^(A,S) did not.Our results provide insight into the molecular mechanism of climacteric and non-climacteric fruit ripening in melon.
文摘Dear Editor, Brassica rapa is an important crop and a model plant for studying Brassica genome evolution and gene function. The silique of B. rapa derived from the gynoecium nor- mally consists of two carpels that are separated by a false septum, and thus has two Iocules （bilocular）. Multilocular （more than two carpels） lines of B. rapa have been discov- ered in nature and are considered advantageous because the multilocular type could potentially increase the seed yield by producing more seeds per silique than the biloc- ular type. However, the molecular basis of the important seed vield-related trait is ooorlv understood.
