On November 18, 2018, the Future Science Prize Awarding Ceremony was held in Beijing. In the area of life science, Professors Jiayang Li, Longping Yuan, and Qifa Zhang shared the prize for their pioneering contributio...On November 18, 2018, the Future Science Prize Awarding Ceremony was held in Beijing. In the area of life science, Professors Jiayang Li, Longping Yuan, and Qifa Zhang shared the prize for their pioneering contributions in producing high-yield, superior-quality rice through systematic study of molecular mechanisms associated with speci?c rice features and application of novel approaches in rice breeding. The Future Science Prize is also touted as ‘‘China’s Nobel Prize", fully af?rming their achievements in rice basic research and breeding.展开更多
Gibberellin (GA) 2-oxidase plays a key role in the GA catabolic pathway through 2β-hydroxylation.In the present study,we isolated a CaMV 35S-enhancer activation tagged mutant,H032.This mutant exhibited a dominant d...Gibberellin (GA) 2-oxidase plays a key role in the GA catabolic pathway through 2β-hydroxylation.In the present study,we isolated a CaMV 35S-enhancer activation tagged mutant,H032.This mutant exhibited a dominant dwarf and GA-deficient phenotype,with a final stature that was less than half of its wild-type counterpart.The endogenous bioactive GAs are markedly decreased in the H032 mutant,and application of bioactive GAs (GA3 or GA4) can reverse the dwarf phenotype.The integrated T-DNA was detected 12.8 kb upstream of the OsGA2ox6 in the H032 genome by TAIL-PCR.An increased level of OsGA2ox6 mRNA was detected at a high level in the H032 mutant,which might be due to the enhancer role of the CaMV 35S promoter.RNAi and ectopic expression analysis of OsGA2ox6 indicated that the dwarf trait and the decreased levels of bioactive GAs in the H032 mutant were a result of the up-regulation of the OsGA2ox6 gene.BLASTP analysis revealed that OsGA2ox6 belongs to the class III of GA 2-oxidases,which is a novel type of GA2ox that uses C20-GAs (GA12 and/or GA53) as the substrates.Interestingly,we found that a GA biosynthesis inhibitor,paclobutrazol,positively regulated the OsGA2ox6 gene.Unlike the over-expression of OsGA2ox1,which led to a high rate of seed abortion,the H032 mutant retained normal flowering and seed production.These results indicate that OsGA2ox6 mainly affects plant stature,and the dominant dwarf trait of the H032 mutant can be used as an efficient dwarf resource in rice breeding.展开更多
Although there is evident homology among reproductive organs when comparing Poaceae (grass) and eudicots, the identity of grass specific organs, such as lodicules, palea, lemma, and glumes has been the subject of a ...Although there is evident homology among reproductive organs when comparing Poaceae (grass) and eudicots, the identity of grass specific organs, such as lodicules, palea, lemma, and glumes has been the subject of a vast and largely inconclusive discussion. Here we provide some direct evidence to support the idea that the empty glumes of rice (Oryza sativa) are counterparts of lemmas. We show that the development of empty glumes is regulated by ELE (elongated empty glume), which belongs to a plant specific novel gene family. Mutations at the ELE locus cause elongated empty glumes, which mimic the lemmas and have the epidermal morphology of lemmas with four or five vascular bundles. As a nuclear-localized gene, ELE is specifically expressed at the empty glumes of immature spikelets, and its ectopic expression causes many floral development defects, including lemma-like palea, extra palea-like structures, elongated lodicules, extra stamens and stigmas. Our result suggests that empty glumes are lemmas of the sterile florets located at the lateral side of the rice spikelet, and ELE acts as a regulator restraining its growth to maintain its small size in wild-type plants.展开更多
Cuticular wax forms a hydrophobic barrier on aerial plant organs; it plays an important role in protecting a plant from damage caused by many forms of environmental stress. In the present study, we characterized a ric...Cuticular wax forms a hydrophobic barrier on aerial plant organs; it plays an important role in protecting a plant from damage caused by many forms of environmental stress. In the present study, we characterized a rice leaf wax-deficient mutant osgll-1 derived from a spontaneous mutation, which exhibited a wax-deficient and highly hydro- philic leaf phenotype. We cloned the OsGLI-1 gene by the map-based cloning method and performed a complementation test to confirm the function of the candidate gene. Molecular studies revealed that OsGLI-1 was a member of the OsGL1 family, and contained regions that were homologous to some regions in sterol desaturases and short-chain dehydro- genases/reductases. Compared to the wild-type, the osgll-1 mutant showed decreased cuticular wax deposition, thinner cuticular membrane, decreased chlorophyll leaching, increased rate of water loss, and enhanced sensitivity to drought. OsGL 1-1 is expressed ubiquitously in rice. The transient expression of OsGLl-l-green fluorescent protein fusion protein indicated that OsGLI-1 is localized in the cytoplasm, plasma membrane, and nucleus.展开更多
Apomixis is an asexual reproduction way of plants that can produce clonal offspring through seeds.In this study,we introduced apomixis into rice(Oryza sativa)by mutating OsSPO11-1,OsREC8,OsOSD1,and OsMATL through a CR...Apomixis is an asexual reproduction way of plants that can produce clonal offspring through seeds.In this study,we introduced apomixis into rice(Oryza sativa)by mutating OsSPO11-1,OsREC8,OsOSD1,and OsMATL through a CRISPR/Cas9 system.The quadruple mutant showed a transformation from meiosis to mitosis and produced clonal diploid gametes.With mutated Osmatl,which gives rise to haploid induction in plants,the quadruple mutant is expected to be able to be produced apomictic diploid offspring.We named this quadruple mutant as AOP(Apomictic Offspring Producer)for its ability to produce apomictic offspring.展开更多
The pigment Is an important character in plant development. In the present study, we characterized and fine mapped one Inhibitor for brown furrows gene (ibf) in rice (Oryza sativa L.). In the ibf mutant, brown pig...The pigment Is an important character in plant development. In the present study, we characterized and fine mapped one Inhibitor for brown furrows gene (ibf) in rice (Oryza sativa L.). In the ibf mutant, brown pigments specifically accumulate in the furrows of hulls as seeds mature and reach a maximum level In dry seeds. Genetic analysis showed that the mutant phenotype is controlled by one recessive nuclear gene, which was finally mapped In a 90-kb region on the long arm of chromosome 9. Polymerase chain reaction and Southern blotting analysis revealed that there was a 26 kb deletion in the 90-kb region in the mutant. Since all the open reading frames outside the gap In the delimited region had no detectable difference in DNA sequence with the wild-type, we postulated that the ibf locus should be located in the gap. Through gene annotation and reverse transcription-polymerase chain reaction (RT-PCR) analysis, we selected OsKF1 encoding a kelch repeat-containing F-box family protein as the candidate gene of ibf.展开更多
MSH5, a meiosis-specific member of the MutS-homolog family, is required for normal level of recombination in budding yeast, mice, Caenorhabditis elegans, and Arabidopsis. Here, we report the identification and charact...MSH5, a meiosis-specific member of the MutS-homolog family, is required for normal level of recombination in budding yeast, mice, Caenorhabditis elegans, and Arabidopsis. Here, we report the identification and characterization of its rice homolog, OsMSH5, and demonstrate its function in rice meiosis. Five independent Osmsh5 mutants exhibited normal vegetative growth and severe sterility. The synaptonemal complex is well installed in Osmsh5, while the chiasma frequency is greatly reduced to approximately 10% of that observed in the wild-type, leading to the homologous non- disjunction and complete sterile phenotype. OsMSH5 is predominantly expressed in panicles. Immunofluorescence studies indicate that OsMSH5 chromosomal localization is limited to the early meiotic prophase I. OsMSH5 can be loaded onto meiotic chromosomes in Oszip4, Osmer3, and hellO. However, those ZMM proteins cannot be localized normally in the absence of OsMSH5. Furthermore, the residual chiasmata were shown to be the least frequent among the zmm mutants, including Osmer3, Oszip4, hellO, and Osmsh5. Taken together, we propose that OsMSH5 functions upstream of OsZIP4, OsMER3, and HEIl0 in class I crossover formation.展开更多
Dear Editor,Meiotic recombination is initiated by the generation of DNA double-strand breaks (DSBs), which are catalyzed by the Spo11 protein (de Massy, 2013). Two key findings point to the role of Spo11 as the in...Dear Editor,Meiotic recombination is initiated by the generation of DNA double-strand breaks (DSBs), which are catalyzed by the Spo11 protein (de Massy, 2013). Two key findings point to the role of Spo11 as the initiator of DSB formation in budding yeast: (1) Spo11 is linked to the 5' termini of the broken DNA molecules in rad50s mutants, whose meiosis has been blocked at the stage of the cleavaqe reaction ('Keenev et al., 1997).展开更多
An awned rice(Oryza sativa) plant carrying a tiny extra chromosome was discovered among the progeny of a telotrisomic line 2nt4L. Fluorescence in situ hybridization(FISH) using chromosome specific BAC clones revea...An awned rice(Oryza sativa) plant carrying a tiny extra chromosome was discovered among the progeny of a telotrisomic line 2nt4L. Fluorescence in situ hybridization(FISH) using chromosome specific BAC clones revealed that this extra chromosome was a ring chromosome derived from part of the long arm of chromosome 4. So the aneuploidy plant was accordingly named as 2nt4L ring. We did not detect any Cent O FISH signals on the ring chromosome, and found only the centromeric probe Centromeric Retrotransposon of Rice(CRR) was co-localized with the centromere-specific histone CENH3 as revealed by sequential FISH after immunodetection. The extra ring chromosome exhibited a unique segregation pattern during meiosis, including no pairing between the ring chromosome and normal chromosome 4during prophase I and pre-separation of sister chromatids at anaphase I.展开更多
基金the financial support from the National Natural Science Foundation of China (Nos. U2141215, 52105384 and 52075325)the support of Materials Genome Initiative Center, Shanghai Jiao Tong University, China。
文摘On November 18, 2018, the Future Science Prize Awarding Ceremony was held in Beijing. In the area of life science, Professors Jiayang Li, Longping Yuan, and Qifa Zhang shared the prize for their pioneering contributions in producing high-yield, superior-quality rice through systematic study of molecular mechanisms associated with speci?c rice features and application of novel approaches in rice breeding. The Future Science Prize is also touted as ‘‘China’s Nobel Prize", fully af?rming their achievements in rice basic research and breeding.
基金supported by grants from the Ministry of Sciences and Technology of China (No. 2005CB120805 and 2006AA10A101)the National Natural Science Foundation of China (No. 30621001 and 30871512)
文摘Gibberellin (GA) 2-oxidase plays a key role in the GA catabolic pathway through 2β-hydroxylation.In the present study,we isolated a CaMV 35S-enhancer activation tagged mutant,H032.This mutant exhibited a dominant dwarf and GA-deficient phenotype,with a final stature that was less than half of its wild-type counterpart.The endogenous bioactive GAs are markedly decreased in the H032 mutant,and application of bioactive GAs (GA3 or GA4) can reverse the dwarf phenotype.The integrated T-DNA was detected 12.8 kb upstream of the OsGA2ox6 in the H032 genome by TAIL-PCR.An increased level of OsGA2ox6 mRNA was detected at a high level in the H032 mutant,which might be due to the enhancer role of the CaMV 35S promoter.RNAi and ectopic expression analysis of OsGA2ox6 indicated that the dwarf trait and the decreased levels of bioactive GAs in the H032 mutant were a result of the up-regulation of the OsGA2ox6 gene.BLASTP analysis revealed that OsGA2ox6 belongs to the class III of GA 2-oxidases,which is a novel type of GA2ox that uses C20-GAs (GA12 and/or GA53) as the substrates.Interestingly,we found that a GA biosynthesis inhibitor,paclobutrazol,positively regulated the OsGA2ox6 gene.Unlike the over-expression of OsGA2ox1,which led to a high rate of seed abortion,the H032 mutant retained normal flowering and seed production.These results indicate that OsGA2ox6 mainly affects plant stature,and the dominant dwarf trait of the H032 mutant can be used as an efficient dwarf resource in rice breeding.
基金supported by grants from the Ministry of Sciences and Technology of China (No. 2008ZX08009-003 and 2009CB118500)the National Natural Sci-ence Foundation of China (No. 30621001 and 30900885)
文摘Although there is evident homology among reproductive organs when comparing Poaceae (grass) and eudicots, the identity of grass specific organs, such as lodicules, palea, lemma, and glumes has been the subject of a vast and largely inconclusive discussion. Here we provide some direct evidence to support the idea that the empty glumes of rice (Oryza sativa) are counterparts of lemmas. We show that the development of empty glumes is regulated by ELE (elongated empty glume), which belongs to a plant specific novel gene family. Mutations at the ELE locus cause elongated empty glumes, which mimic the lemmas and have the epidermal morphology of lemmas with four or five vascular bundles. As a nuclear-localized gene, ELE is specifically expressed at the empty glumes of immature spikelets, and its ectopic expression causes many floral development defects, including lemma-like palea, extra palea-like structures, elongated lodicules, extra stamens and stigmas. Our result suggests that empty glumes are lemmas of the sterile florets located at the lateral side of the rice spikelet, and ELE acts as a regulator restraining its growth to maintain its small size in wild-type plants.
文摘Cuticular wax forms a hydrophobic barrier on aerial plant organs; it plays an important role in protecting a plant from damage caused by many forms of environmental stress. In the present study, we characterized a rice leaf wax-deficient mutant osgll-1 derived from a spontaneous mutation, which exhibited a wax-deficient and highly hydro- philic leaf phenotype. We cloned the OsGLI-1 gene by the map-based cloning method and performed a complementation test to confirm the function of the candidate gene. Molecular studies revealed that OsGLI-1 was a member of the OsGL1 family, and contained regions that were homologous to some regions in sterol desaturases and short-chain dehydro- genases/reductases. Compared to the wild-type, the osgll-1 mutant showed decreased cuticular wax deposition, thinner cuticular membrane, decreased chlorophyll leaching, increased rate of water loss, and enhanced sensitivity to drought. OsGL 1-1 is expressed ubiquitously in rice. The transient expression of OsGLl-l-green fluorescent protein fusion protein indicated that OsGLI-1 is localized in the cytoplasm, plasma membrane, and nucleus.
基金supported by grants from the Ministry of Sciences and Technology of China (2016YFD0101801)the National Natural Science Foundation of China (31771363)
文摘Apomixis is an asexual reproduction way of plants that can produce clonal offspring through seeds.In this study,we introduced apomixis into rice(Oryza sativa)by mutating OsSPO11-1,OsREC8,OsOSD1,and OsMATL through a CRISPR/Cas9 system.The quadruple mutant showed a transformation from meiosis to mitosis and produced clonal diploid gametes.With mutated Osmatl,which gives rise to haploid induction in plants,the quadruple mutant is expected to be able to be produced apomictic diploid offspring.We named this quadruple mutant as AOP(Apomictic Offspring Producer)for its ability to produce apomictic offspring.
基金Supported by Grants from the Ministry of Sciences and Technology of China (2005CB120805), the Chinese Academy of Sciences and the National Natural Science Foundation of China (30325008, 30428019 and 305300).The authors thank Dr Khush at the International Rice Research Institute, the Philippines (IRRI) for providing the original ibfmutant.
文摘The pigment Is an important character in plant development. In the present study, we characterized and fine mapped one Inhibitor for brown furrows gene (ibf) in rice (Oryza sativa L.). In the ibf mutant, brown pigments specifically accumulate in the furrows of hulls as seeds mature and reach a maximum level In dry seeds. Genetic analysis showed that the mutant phenotype is controlled by one recessive nuclear gene, which was finally mapped In a 90-kb region on the long arm of chromosome 9. Polymerase chain reaction and Southern blotting analysis revealed that there was a 26 kb deletion in the 90-kb region in the mutant. Since all the open reading frames outside the gap In the delimited region had no detectable difference in DNA sequence with the wild-type, we postulated that the ibf locus should be located in the gap. Through gene annotation and reverse transcription-polymerase chain reaction (RT-PCR) analysis, we selected OsKF1 encoding a kelch repeat-containing F-box family protein as the candidate gene of ibf.
基金This work was supported by grants from the Ministry of Sciences and Technology of China (2011CB944602 and 2012AA10A301)the State Key Laboratory of Plant Genomics of China (2012A0527)and the National Natural Science Foundation of China (31160223 and 31230038). No conflict of interest declared.
文摘MSH5, a meiosis-specific member of the MutS-homolog family, is required for normal level of recombination in budding yeast, mice, Caenorhabditis elegans, and Arabidopsis. Here, we report the identification and characterization of its rice homolog, OsMSH5, and demonstrate its function in rice meiosis. Five independent Osmsh5 mutants exhibited normal vegetative growth and severe sterility. The synaptonemal complex is well installed in Osmsh5, while the chiasma frequency is greatly reduced to approximately 10% of that observed in the wild-type, leading to the homologous non- disjunction and complete sterile phenotype. OsMSH5 is predominantly expressed in panicles. Immunofluorescence studies indicate that OsMSH5 chromosomal localization is limited to the early meiotic prophase I. OsMSH5 can be loaded onto meiotic chromosomes in Oszip4, Osmer3, and hellO. However, those ZMM proteins cannot be localized normally in the absence of OsMSH5. Furthermore, the residual chiasmata were shown to be the least frequent among the zmm mutants, including Osmer3, Oszip4, hellO, and Osmsh5. Taken together, we propose that OsMSH5 functions upstream of OsZIP4, OsMER3, and HEIl0 in class I crossover formation.
文摘Dear Editor,Meiotic recombination is initiated by the generation of DNA double-strand breaks (DSBs), which are catalyzed by the Spo11 protein (de Massy, 2013). Two key findings point to the role of Spo11 as the initiator of DSB formation in budding yeast: (1) Spo11 is linked to the 5' termini of the broken DNA molecules in rad50s mutants, whose meiosis has been blocked at the stage of the cleavaqe reaction ('Keenev et al., 1997).
基金supported by grants from the National Natural Science Foundation of China (Nos. U1302261, 31360260 and 31401357).
文摘An awned rice(Oryza sativa) plant carrying a tiny extra chromosome was discovered among the progeny of a telotrisomic line 2nt4L. Fluorescence in situ hybridization(FISH) using chromosome specific BAC clones revealed that this extra chromosome was a ring chromosome derived from part of the long arm of chromosome 4. So the aneuploidy plant was accordingly named as 2nt4L ring. We did not detect any Cent O FISH signals on the ring chromosome, and found only the centromeric probe Centromeric Retrotransposon of Rice(CRR) was co-localized with the centromere-specific histone CENH3 as revealed by sequential FISH after immunodetection. The extra ring chromosome exhibited a unique segregation pattern during meiosis, including no pairing between the ring chromosome and normal chromosome 4during prophase I and pre-separation of sister chromatids at anaphase I.