The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberati...The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberation Organization (PLO), opened its fifth general congress on August 3 in Tunis. PLO Chairman and President of the State of Palestine Yasser Arafat and Tunisian President Zine E1 Abidine Ben All addressed the opening ceremony.展开更多
In higher plants, NO3 can induce its own uptake and the magnitude of this induction is positively related to the external anion concentration. This phenomenon has been characterized in both herbaceous and woody plants...In higher plants, NO3 can induce its own uptake and the magnitude of this induction is positively related to the external anion concentration. This phenomenon has been characterized in both herbaceous and woody plants. Here,different adaptation strategies of roots from two maize（Zea mays L., ZmAGOs） inbred lines differing in nitrogen use efficiency（NUE） and exhibiting different timing of induction were discussed by investigating NO3 ‐induced changes in their transcriptome. Lo5 line（high NUE） showing the maximum rate of NO3 uptake 4 h after the provision of 200 mmol/L NO3 treatment modulated a higher number of transcripts relative to T250（low NUE） that peaked after 12 h. The two inbred lines share only 368 transcripts that are modulated by the treatment with NO3 and behaved differently when transcripts involved in anion uptake and assimilation were analyzed. T250 line responded to the NO3 induction modulating this group of Researchgenes as reported for several plant species. On the contrary,the Lo5 line did not exhibit during the induction changes in this set of genes. Obtained data suggest the importance of exploring the physiological and molecular variations among different maize genotypes in response to environmental clues like NO3 provision, in order to understand mechanisms underlying NUE.展开更多
Double haploid production is the most effective way to create true-breeding lines in a single generation.In Arabidopsis,haploid induction via mutation of the centromere-specific histone H3(cenH3)has been shown when th...Double haploid production is the most effective way to create true-breeding lines in a single generation.In Arabidopsis,haploid induction via mutation of the centromere-specific histone H3(cenH3)has been shown when the mutant is outcrossed to the wild-type,and the wild-type genome remains in the haploid progeny.However,factors that affect haploid induction are still poorly understood.Here,we report that a mutant of the cenH3 assembly factor Kinetochore Null2(KNL2)can be used as a haploid inducer when pollinated by the wild-type.We discovered that short-term temperature stress of the knl2 mutant increased the efficiency of haploid induction 10-fold.We also demonstrated that a point mutation in the CENPC-k motif of KNL2 is sufficient to generate haploid-inducing lines,suggesting that haploidinducing lines in crops can be identified in a naturally occurring or chemically induced mutant population,avoiding the generic modification(GM)approach at any stage.Furthermore,a cenh3-4 mutant functioned as a haploid inducer in response to short-term heat stress,even though it did not induce haploids under standard conditions.Thus,we identified KNL2 as a new target gene for the generation of haploid-inducer lines and showed that exposure of centromeric protein mutants to high temperature strongly increases their haploid induction efficiency.展开更多
文摘The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberation Organization (PLO), opened its fifth general congress on August 3 in Tunis. PLO Chairman and President of the State of Palestine Yasser Arafat and Tunisian President Zine E1 Abidine Ben All addressed the opening ceremony.
文摘In higher plants, NO3 can induce its own uptake and the magnitude of this induction is positively related to the external anion concentration. This phenomenon has been characterized in both herbaceous and woody plants. Here,different adaptation strategies of roots from two maize（Zea mays L., ZmAGOs） inbred lines differing in nitrogen use efficiency（NUE） and exhibiting different timing of induction were discussed by investigating NO3 ‐induced changes in their transcriptome. Lo5 line（high NUE） showing the maximum rate of NO3 uptake 4 h after the provision of 200 mmol/L NO3 treatment modulated a higher number of transcripts relative to T250（low NUE） that peaked after 12 h. The two inbred lines share only 368 transcripts that are modulated by the treatment with NO3 and behaved differently when transcripts involved in anion uptake and assimilation were analyzed. T250 line responded to the NO3 induction modulating this group of Researchgenes as reported for several plant species. On the contrary,the Lo5 line did not exhibit during the induction changes in this set of genes. Obtained data suggest the importance of exploring the physiological and molecular variations among different maize genotypes in response to environmental clues like NO3 provision, in order to understand mechanisms underlying NUE.
基金supported by the German Federal Ministry of Education and Research(Plant 2030,Project 031B0192NN,HaploTools)the Deutsche Forschungsgemeinschaft(LE2299/3-1 and LE2299/5-1)the European Regional Development Fund-Project"REMAP"(CZ.02.1.01/0.0/0.0/15_003/0000479)to K.R.
文摘Double haploid production is the most effective way to create true-breeding lines in a single generation.In Arabidopsis,haploid induction via mutation of the centromere-specific histone H3(cenH3)has been shown when the mutant is outcrossed to the wild-type,and the wild-type genome remains in the haploid progeny.However,factors that affect haploid induction are still poorly understood.Here,we report that a mutant of the cenH3 assembly factor Kinetochore Null2(KNL2)can be used as a haploid inducer when pollinated by the wild-type.We discovered that short-term temperature stress of the knl2 mutant increased the efficiency of haploid induction 10-fold.We also demonstrated that a point mutation in the CENPC-k motif of KNL2 is sufficient to generate haploid-inducing lines,suggesting that haploidinducing lines in crops can be identified in a naturally occurring or chemically induced mutant population,avoiding the generic modification(GM)approach at any stage.Furthermore,a cenh3-4 mutant functioned as a haploid inducer in response to short-term heat stress,even though it did not induce haploids under standard conditions.Thus,we identified KNL2 as a new target gene for the generation of haploid-inducer lines and showed that exposure of centromeric protein mutants to high temperature strongly increases their haploid induction efficiency.
