Foxtail millet（Setaria italica（L.）P.Beauv）is a naturally stress tolerant crop.Compared to other gramineous crops,it has relatively stronger drought and lower nutrition stress tolerance traits.To date,the scope of ...Foxtail millet（Setaria italica（L.）P.Beauv）is a naturally stress tolerant crop.Compared to other gramineous crops,it has relatively stronger drought and lower nutrition stress tolerance traits.To date,the scope of functional genomics research in foxtail millet（S.italic L.）has been quite limited.NAC（NAM,ATAF1/2 and CUC2）-like transcription factors are known to be involved in various biological processes,including abiotic stress responses.In our previous foxtail millet（S.italic L.）RNA seq analysis,we found that the expression of a NAC-like transcription factor,SiNAC110,could be induced by drought stress;additionally,other references have reported that SiNAC110 expression could be induced by abiotic stress.So,we here selected SiNAC110 for further characterization and functional analysis.First,the predicted SiNAC110 protein encoded indicated SiNAC110 has a conserved NAM（no apical meristem）domain between the 11–139 amino acid positions.Phylogenetic analysis then indicated that SiNAC110 belongs to subfamily III of the NAC gene family.Subcellular localization analysis revealed that the SiNAC110-GFP fusion protein was localized to the nucleus in Arabidopsis protoplasts.Gene expression profiling analysis indicated that expression of SiNAC110 was induced by dehydration,high salinity and other abiotic stresses.Gene functional analysis using SiNAC110 overexpressed Arabidopsis plants indicated that,under drought and high salt stress conditions,the seed germination rate,root length,root surface area,fresh weight,and dry weight of the SiNAC110 overexpressed lines were significantly higher than the wild type（WT）,suggesting that the SiNAC110 overexpressed lines had enhanced tolerance to drought and high salt stresses.However,overexpression of SiN AC110 did not affect the sensitivity of SiNAC110 overexpressed lines to abscisic acid（ABA）treatment.Expression analysis of genes involved in proline synthesis,Na＋/K＋transport,drought responses,and aqueous transport proteins were higher in the SiNAC110overexpressed lines than in the WT,whereas expression of ABA-dependent pathway genes did not change.These results indicated that overexpression of SiNAC110 conferred tolerance to drought and high salt stresses,likely through influencing the regulation of proline biosynthesis,ion homeostasis and osmotic balance.Therefore,SiNAC110 appears to function in the ABA-independent abiotic stress response pathway in plants.展开更多
Salinity severely affects plant growth and development.Thus,it is crucial to identify the genes functioning in salt stress response and unravel the mechanism by which plants against salt stress.This study used the pho...Salinity severely affects plant growth and development.Thus,it is crucial to identify the genes functioning in salt stress response and unravel the mechanism by which plants against salt stress.This study used the phosphoproteomic assay and found that 123 of the 4000 quantitative analyzed phosphopeptides were induced by salt stress.The functional annotation of the non-redundant protein database(NR)showed 23 differentially expressed transcription factors,including a phosphopeptide covering the Serine 31 in the RAV(related to ABI3/VP1)transcription factor(named SiRAV1).SiRAV1 was located in the nucleus.Phenotypic and physiological analysis showed that overexpressing SiRAV1 in foxtail millet enhanced salt tolerance and alleviated the salt-induced increases of H_(2)O_(2) accumulation,malondialdehyde(MDA)content,and percent of electrolyte leakage.Further analysis showed that SiRAV1 positively regulated SiCAT expression to modulate the catalase(CAT)activity by directly binding to the SiCAT promoter in vivo and in vitro.Moreover,we found that phosphorylation of SiRAV1 at the Ser31 site positively regulated salt tolerance in foxtail millet via enhancing its binding ability to SiCAT promoter but did not affect its subcellular localization.Overall,our results define a mechanism for SiRAV1 function in salt response where salt-triggered phosphorylation of SiRAV1 at Ser31 enhances its binding ability to SiCAT promoter,and the increased SiCAT expression contributes to salt tolerance in foxtail millet.展开更多
Convective heat transfer characteristics of molten salt in receiver tube under axially and circumferentially non-uniform(ACN)heat flux were experimentally investigated under Reynolds number of 16000 to 58000 and Prand...Convective heat transfer characteristics of molten salt in receiver tube under axially and circumferentially non-uniform(ACN)heat flux were experimentally investigated under Reynolds number of 16000 to 58000 and Prandtl number of 4.6 to 7.5.The results showed that flow rate,flow direction and non-uniform heat flux directly affected molten salt transfer.As coating thickness and flow velocity increased,the difference of outer wall temperature in coating side and molten salt temperature dropped.The average Nusselt number in entrance section was larger than that in middle and end sections for higher Prandtl number.The axial wall temperature difference in coating side with counter-flow heating was lower than that with parallel-flow heating,and receiver tube with counter-flow heating will cause smaller axial thermal stress.From experiment measurement and Sieder-Tate correlation,heat transfer correlation of molten salt in tube under ACN heat flux was obtained by using circumferential heat flux ratio and axial heat flux ratio,and it fit with experimental data with maximum deviation of 5%.展开更多
基金funded by the National Key Project for Research on Transgenic Biology, China (2016ZX08002-002)the Innovation Project of Chinese Academy of Agricultural Sciences
文摘Foxtail millet（Setaria italica（L.）P.Beauv）is a naturally stress tolerant crop.Compared to other gramineous crops,it has relatively stronger drought and lower nutrition stress tolerance traits.To date,the scope of functional genomics research in foxtail millet（S.italic L.）has been quite limited.NAC（NAM,ATAF1/2 and CUC2）-like transcription factors are known to be involved in various biological processes,including abiotic stress responses.In our previous foxtail millet（S.italic L.）RNA seq analysis,we found that the expression of a NAC-like transcription factor,SiNAC110,could be induced by drought stress;additionally,other references have reported that SiNAC110 expression could be induced by abiotic stress.So,we here selected SiNAC110 for further characterization and functional analysis.First,the predicted SiNAC110 protein encoded indicated SiNAC110 has a conserved NAM（no apical meristem）domain between the 11–139 amino acid positions.Phylogenetic analysis then indicated that SiNAC110 belongs to subfamily III of the NAC gene family.Subcellular localization analysis revealed that the SiNAC110-GFP fusion protein was localized to the nucleus in Arabidopsis protoplasts.Gene expression profiling analysis indicated that expression of SiNAC110 was induced by dehydration,high salinity and other abiotic stresses.Gene functional analysis using SiNAC110 overexpressed Arabidopsis plants indicated that,under drought and high salt stress conditions,the seed germination rate,root length,root surface area,fresh weight,and dry weight of the SiNAC110 overexpressed lines were significantly higher than the wild type（WT）,suggesting that the SiNAC110 overexpressed lines had enhanced tolerance to drought and high salt stresses.However,overexpression of SiN AC110 did not affect the sensitivity of SiNAC110 overexpressed lines to abscisic acid（ABA）treatment.Expression analysis of genes involved in proline synthesis,Na＋/K＋transport,drought responses,and aqueous transport proteins were higher in the SiNAC110overexpressed lines than in the WT,whereas expression of ABA-dependent pathway genes did not change.These results indicated that overexpression of SiNAC110 conferred tolerance to drought and high salt stresses,likely through influencing the regulation of proline biosynthesis,ion homeostasis and osmotic balance.Therefore,SiNAC110 appears to function in the ABA-independent abiotic stress response pathway in plants.
基金This work was funded by the National Natural Science Foundation of China(31902062)the South China Botanical Garden,Chinese Academy of Sciences(QNXM-02).
文摘Salinity severely affects plant growth and development.Thus,it is crucial to identify the genes functioning in salt stress response and unravel the mechanism by which plants against salt stress.This study used the phosphoproteomic assay and found that 123 of the 4000 quantitative analyzed phosphopeptides were induced by salt stress.The functional annotation of the non-redundant protein database(NR)showed 23 differentially expressed transcription factors,including a phosphopeptide covering the Serine 31 in the RAV(related to ABI3/VP1)transcription factor(named SiRAV1).SiRAV1 was located in the nucleus.Phenotypic and physiological analysis showed that overexpressing SiRAV1 in foxtail millet enhanced salt tolerance and alleviated the salt-induced increases of H_(2)O_(2) accumulation,malondialdehyde(MDA)content,and percent of electrolyte leakage.Further analysis showed that SiRAV1 positively regulated SiCAT expression to modulate the catalase(CAT)activity by directly binding to the SiCAT promoter in vivo and in vitro.Moreover,we found that phosphorylation of SiRAV1 at the Ser31 site positively regulated salt tolerance in foxtail millet via enhancing its binding ability to SiCAT promoter but did not affect its subcellular localization.Overall,our results define a mechanism for SiRAV1 function in salt response where salt-triggered phosphorylation of SiRAV1 at Ser31 enhances its binding ability to SiCAT promoter,and the increased SiCAT expression contributes to salt tolerance in foxtail millet.
基金supported by National Natural Science Foundation of China(No.51606227,U1601215)Natural Science Foundation of Guangdong Province(2017B030308004)。
文摘Convective heat transfer characteristics of molten salt in receiver tube under axially and circumferentially non-uniform(ACN)heat flux were experimentally investigated under Reynolds number of 16000 to 58000 and Prandtl number of 4.6 to 7.5.The results showed that flow rate,flow direction and non-uniform heat flux directly affected molten salt transfer.As coating thickness and flow velocity increased,the difference of outer wall temperature in coating side and molten salt temperature dropped.The average Nusselt number in entrance section was larger than that in middle and end sections for higher Prandtl number.The axial wall temperature difference in coating side with counter-flow heating was lower than that with parallel-flow heating,and receiver tube with counter-flow heating will cause smaller axial thermal stress.From experiment measurement and Sieder-Tate correlation,heat transfer correlation of molten salt in tube under ACN heat flux was obtained by using circumferential heat flux ratio and axial heat flux ratio,and it fit with experimental data with maximum deviation of 5%.
