Herbicide resistance in crop plants is valuable for integrated weed management in agriculture. Herbicide resistant rice, in particular, is important to management of weedy rice, a close relative of cultivated rice and...Herbicide resistance in crop plants is valuable for integrated weed management in agriculture. Herbicide resistant rice, in particular, is important to management of weedy rice, a close relative of cultivated rice and a noxious weed prevalent in rice fields that remains challenging to farmers worldwide. Herbicide resistant plants can be obtained through transgenic approach or by mutagenesis of regular plant and screening of mutants with elevated resistance to herbicide. In this study, we conducted ethyl methyl sulfonate mutagenesis(EMS) to elite indica cultivar Huanghuazhan(HHZ) and screened for mutants resistant to imazapic, a herbicide that can inhibit the acetolactate synthase(ALS) in plants. We obtained three mutants of Os ALS gene that have not been reported previously in rice. One of the mutants, with Trp_(548) changed to Met(W_(548)M), was analyzed in more details in this study. This mutation had no negative effect on the plant physiology and morphology as well as rice yield. Compared with the imidazolinone-resistant mutant S_(627)N(Ser_(627) changed to Asn) that has been deployed for Clearfield rice development, W_(548)M mutant showed high levels of resistance to a broad spectrum of five families of ALSinhibiting herbicides, in addition to a higher level of resistance to herbicides of the imidazolinone family.The herbicide-resistance was stably inherited by crossing into other rice lines. Thus, the W_(548)M mutation provides a valuable resource for breeding of herbicide resistant rice and weed management.展开更多
The breeding and large-scale application of hybrid rice contribute significantly to the food supply worldwide.Currently,hybrid seed production uses cytoplasmic male sterile(CMS)lines or photoperiod/thermo-sensitive ge...The breeding and large-scale application of hybrid rice contribute significantly to the food supply worldwide.Currently,hybrid seed production uses cytoplasmic male sterile(CMS)lines or photoperiod/thermo-sensitive genic male sterile(PTGMS)lines as female parent.Despite huge successes,both systems have intrinsic problems.CMS systems are mainly restricted by the narrow restorer resources that make it difficult to breed superior hybrids,while PTGMS systems are limited by conditional sterility of the male sterile lines that makes the propagation of both PTGMS seeds and hybrid seeds vulnerable to unpredictable climate changes.Recessive nuclear male sterile(NMS)lines insensitive to environmental conditions are widely distributed and are ideal for hybrid rice breeding and production,but the lack of effective ways to propagate the pure NMS lines in a large scale renders it impossible to use them for hybrid rice production.The development of"the third-generation hybrid rice technology"enables efficient propagation of the pure NMS lines in commercial scale.This paper discusses the establishment of"the thirdgeneration hybrid rice technology"and further innovations.This new technology breaks the limitations of CMS and PTGMS systems and will bring a big leap forward in hybrid rice production.展开更多
Phosphatidylinositol 4,5-bisphosphate(PI(4,5)P_(2))is known to be an instrumental anionic phospholipid in governing pollen germination and pollen tube growth.However,the precise functions and regulatory mechanisms of ...Phosphatidylinositol 4,5-bisphosphate(PI(4,5)P_(2))is known to be an instrumental anionic phospholipid in governing pollen germination and pollen tube growth.However,the precise functions and regulatory mechanisms of PI(4,5)P_(2) in pollen polarity establishment and germination remain poorly understood.Our previous studies demonstrated the pivotal involvement of Arabidopsis formin homology 5(AtFH5)-dependent vesicle trafficking in polarity establishment of pollen.Here,we observed that PI(4,5)P_(2) accumulated and oscillated at the prospective germination site,a process closely associated with the rotational movement of AtFH5-labeled vesicles.Disruption of the mobility of AtFH5-labeled vesicles,either through AtFH5 mutation or pharmacological treatment,significantly perturbed the accumulation of PI(4,5)P_(2) at the plasma membrane.Subcellular localization and genetic analysis revealed that two phosphatidylinositol 4-phosphate 5-kinases,AtPIP5K1 and AtPIP5K4,are essential for PI(4,5)P_(2) oscillation at the germination site prior to pollen germination.Furthermore,we found that the dynamics of AtPIP5K4 depended on the mobility of AtFH5-labeled vesicles and reduced PI(4,5)P_(2) in turn disturbed the attachment of AtFH5-labeled secretory vesicles to the plasma membrane.In conclusion,these findings collectively highlight the reciprocal regulation of AtFH5-labeled secretory vesicles and PI(4,5)P_(2) oscillations at the plasma membrane,providing critical insights into the molecular mechanism underlying polarity establishment during pollen germination.展开更多
Pollen exine contains complex biopolymers of aliphatic lipids and phenolics.Abnormal development of pollen exine often leads to plant sterility.Molecular mechanisms regulating exine formation have been studied extensi...Pollen exine contains complex biopolymers of aliphatic lipids and phenolics.Abnormal development of pollen exine often leads to plant sterility.Molecular mechanisms regulating exine formation have been studied extensively but remain ambiguous.Here we report the analyses of three GDSL esterase/lipase protein genes,OsGELP34,OsGELP110,and OsGELP115,for rice exine for-mation.OsGELP34 was identified by cloning of a male sterile mutant gene.OsGELP34 encodes an endoplasmic reticulum protein and was mainly expressed in anthers during pollen exine formation.osgelp34 mutant displayed abnormal exine and altered expression of a number of key genes required for pollen development.OsGELP110 was previously identified as a gene differentially expressed in meiotic anthers.OsGELP110 was most homologous to OsGELP115,and the two genes showed similar gene expression patterns.Both OsGELP110 and OsGELP115 proteins were localized in peroxisomes.Individual knockout of OsGELP110 and OsGELP115 did not affect the plant fertility,but double knockout of both genes altered the exine structure and rendered the plant male sterile.OsGELP34 is distant from OsGELP110 and OsGELP115 in sequence,and osgelp34 and osgelp110/osgelp115 mutants were different in anther morphology despite both were male sterile.These results suggested that OsGELP34 and OsGELP110/OsGELP115 catalyze different compounds for pollen exine development.展开更多
Pollen grains are covered by exine that protects the pollen from stress and facilitates pollination.Here we isolated a male sterile mutant s13283 in rice exhibiting aborted pollen with abnormal exine and defective ape...Pollen grains are covered by exine that protects the pollen from stress and facilitates pollination.Here we isolated a male sterile mutant s13283 in rice exhibiting aborted pollen with abnormal exine and defective aperture.The mutant gene encodes a novel plasma membrane-localized legume-lectin receptor kinase that we named OsLecRK-S.7.OsLecRK-S.7 was expressed at different levels in all tested tissues and throughout anther development.In vitro kinase assay showed OsLecRK-S.7 capable of autophosporylation.Mutation in s13283(E560K)and mutation of the conserved ATP binding site(K418E)both knocked out the kinase activity.Mass spectrometry showed Thr376,Ser378,Thr386,Thr403,and Thr657 to be the autophosphorylation sites.Mutation of individual autophosphorylation site affected the in vitro kinase activity to different degrees,but did not abolish the gene function in fertility complementation.oslecrk-s.7 mutant plant overexpressing OsLecRK-S.7 recovered male fertility but showed severe growth retardation with reduced number of tillers,and these phenotypes were abolished by E560K or K418E mutation.The results indicated that OsLecRK-S.7 was a key regulator of pollen development.展开更多
Large-scale production of male sterile seeds can be achieved by introducing a fertility-restoration gene linked with a pollen-killer gene into a recessive male sterile mutant.We attempted to construct this system in r...Large-scale production of male sterile seeds can be achieved by introducing a fertility-restoration gene linked with a pollen-killer gene into a recessive male sterile mutant.We attempted to construct this system in rice by using a late-stage pollen-specific(LSP)promoter driving the expression of maizeα-amylase gene ZM-AA1.To obtain such promoters in rice,we conducted comparative RNA-seq analysis of mature pollen with meiosis anther,and compared this with the transcriptomic data of various tissues in the Rice Expression Database,resulting in 269 candidate LSP genes.Initial test of nine LSP genes showed that only the most active OsLSP3 promoter could drive ZM-AA1 to disrupt pollen.We then analyzed an additional 22 LSP genes and found 12 genes stronger than OsLSP3 in late-stage anthers.The promoters of OsLSP5 and OsLSP6 showing higher expression than OsLSP3 at stages 11 and 12 could drive ZM-AA1 to inactivate pollen,while the promoter of OsLSP4 showing higher expression at stage 12 only could not drive ZM-AA1 to disrupt pollen,suggesting that strong promoter activity at stage 11 was critical for pollen inactivation.The strong pollen-specific promoters identified in this study provided valuable tools for genetic engineering of rice male sterile system for hybrid rice production.展开更多
基金supported by Major Program of Guangdong Basic and Applied Research(2019B030302006)National Natural Science Foundation of China(U1901203 and 31901532)+2 种基金Natural Science Foundation of Guangdong Province(2018B030308008 and 2018A0303130270)Shenzhen Commission on Innovation and Technology Programs(JCYJ20180507181837997)China Postdoctoral Science Foundation(2018M633069 and 2019M652920)。
文摘Herbicide resistance in crop plants is valuable for integrated weed management in agriculture. Herbicide resistant rice, in particular, is important to management of weedy rice, a close relative of cultivated rice and a noxious weed prevalent in rice fields that remains challenging to farmers worldwide. Herbicide resistant plants can be obtained through transgenic approach or by mutagenesis of regular plant and screening of mutants with elevated resistance to herbicide. In this study, we conducted ethyl methyl sulfonate mutagenesis(EMS) to elite indica cultivar Huanghuazhan(HHZ) and screened for mutants resistant to imazapic, a herbicide that can inhibit the acetolactate synthase(ALS) in plants. We obtained three mutants of Os ALS gene that have not been reported previously in rice. One of the mutants, with Trp_(548) changed to Met(W_(548)M), was analyzed in more details in this study. This mutation had no negative effect on the plant physiology and morphology as well as rice yield. Compared with the imidazolinone-resistant mutant S_(627)N(Ser_(627) changed to Asn) that has been deployed for Clearfield rice development, W_(548)M mutant showed high levels of resistance to a broad spectrum of five families of ALSinhibiting herbicides, in addition to a higher level of resistance to herbicides of the imidazolinone family.The herbicide-resistance was stably inherited by crossing into other rice lines. Thus, the W_(548)M mutation provides a valuable resource for breeding of herbicide resistant rice and weed management.
基金supported by the National Natural Science Foundation of China(U1901203)Natural Science Foundation of Guangdong Province(2018B030308008 and 2019A1515110671)+2 种基金Major Program of Guangdong Basic and Applied Research(2019B030302006)Shenzhen Commission on Innovation and Technology Programs(JCYJ20180507181837997)China Postdoctoral Science Foundation(2019M662957)。
文摘The breeding and large-scale application of hybrid rice contribute significantly to the food supply worldwide.Currently,hybrid seed production uses cytoplasmic male sterile(CMS)lines or photoperiod/thermo-sensitive genic male sterile(PTGMS)lines as female parent.Despite huge successes,both systems have intrinsic problems.CMS systems are mainly restricted by the narrow restorer resources that make it difficult to breed superior hybrids,while PTGMS systems are limited by conditional sterility of the male sterile lines that makes the propagation of both PTGMS seeds and hybrid seeds vulnerable to unpredictable climate changes.Recessive nuclear male sterile(NMS)lines insensitive to environmental conditions are widely distributed and are ideal for hybrid rice breeding and production,but the lack of effective ways to propagate the pure NMS lines in a large scale renders it impossible to use them for hybrid rice production.The development of"the third-generation hybrid rice technology"enables efficient propagation of the pure NMS lines in commercial scale.This paper discusses the establishment of"the thirdgeneration hybrid rice technology"and further innovations.This new technology breaks the limitations of CMS and PTGMS systems and will bring a big leap forward in hybrid rice production.
基金supported by grants from the National Natural Science Foundation of China(32170335,32470736 and 92254303 to H.Ren,32300572 to Y.Li).
文摘Phosphatidylinositol 4,5-bisphosphate(PI(4,5)P_(2))is known to be an instrumental anionic phospholipid in governing pollen germination and pollen tube growth.However,the precise functions and regulatory mechanisms of PI(4,5)P_(2) in pollen polarity establishment and germination remain poorly understood.Our previous studies demonstrated the pivotal involvement of Arabidopsis formin homology 5(AtFH5)-dependent vesicle trafficking in polarity establishment of pollen.Here,we observed that PI(4,5)P_(2) accumulated and oscillated at the prospective germination site,a process closely associated with the rotational movement of AtFH5-labeled vesicles.Disruption of the mobility of AtFH5-labeled vesicles,either through AtFH5 mutation or pharmacological treatment,significantly perturbed the accumulation of PI(4,5)P_(2) at the plasma membrane.Subcellular localization and genetic analysis revealed that two phosphatidylinositol 4-phosphate 5-kinases,AtPIP5K1 and AtPIP5K4,are essential for PI(4,5)P_(2) oscillation at the germination site prior to pollen germination.Furthermore,we found that the dynamics of AtPIP5K4 depended on the mobility of AtFH5-labeled vesicles and reduced PI(4,5)P_(2) in turn disturbed the attachment of AtFH5-labeled secretory vesicles to the plasma membrane.In conclusion,these findings collectively highlight the reciprocal regulation of AtFH5-labeled secretory vesicles and PI(4,5)P_(2) oscillations at the plasma membrane,providing critical insights into the molecular mechanism underlying polarity establishment during pollen germination.
基金We thank the Microscope Center in Life Science Schoolof Sun Yat-sen University for using their facilities formicroscopic analysis,and Yao-Guang Liu for the CRISPR/Cas9 systemThis work was supported by grants from Major Program of Guangdong Basic and Applied Re-search(grant number 2019B030302006)+3 种基金National Nat-ural Science Foundation of China(grant numbersU1901203 and 31801344)Natural Science Foundation ofGuangdong Province(grant number 2018B030308008)Shenzhen Commission on Innovation and Technology Programs(grant number JCYJ20180507181837997)Guangzhou Science and Technology lnnovation Com-mission(grant number 201804010034).
文摘Pollen exine contains complex biopolymers of aliphatic lipids and phenolics.Abnormal development of pollen exine often leads to plant sterility.Molecular mechanisms regulating exine formation have been studied extensively but remain ambiguous.Here we report the analyses of three GDSL esterase/lipase protein genes,OsGELP34,OsGELP110,and OsGELP115,for rice exine for-mation.OsGELP34 was identified by cloning of a male sterile mutant gene.OsGELP34 encodes an endoplasmic reticulum protein and was mainly expressed in anthers during pollen exine formation.osgelp34 mutant displayed abnormal exine and altered expression of a number of key genes required for pollen development.OsGELP110 was previously identified as a gene differentially expressed in meiotic anthers.OsGELP110 was most homologous to OsGELP115,and the two genes showed similar gene expression patterns.Both OsGELP110 and OsGELP115 proteins were localized in peroxisomes.Individual knockout of OsGELP110 and OsGELP115 did not affect the plant fertility,but double knockout of both genes altered the exine structure and rendered the plant male sterile.OsGELP34 is distant from OsGELP110 and OsGELP115 in sequence,and osgelp34 and osgelp110/osgelp115 mutants were different in anther morphology despite both were male sterile.These results suggested that OsGELP34 and OsGELP110/OsGELP115 catalyze different compounds for pollen exine development.
基金This work was supported by the Major Program of Guangdong Basic and Applied Research(2019B030302006)National Natural Science Foundation of China(U1901203,31801344,andU1704232)+3 种基金Natural Science Foundation of Guangdong Province(2018B030308008,2017A030313104,and 2018A0303130270)Shenzhen Commission on Innovation and Technology Programs(JCYJ20180507181837997)China Postdoctoral Science Foundation(2019M652938)the Innovation Project of Graduate School of South China Normal Uni-versity(2017LKXM011).
文摘Pollen grains are covered by exine that protects the pollen from stress and facilitates pollination.Here we isolated a male sterile mutant s13283 in rice exhibiting aborted pollen with abnormal exine and defective aperture.The mutant gene encodes a novel plasma membrane-localized legume-lectin receptor kinase that we named OsLecRK-S.7.OsLecRK-S.7 was expressed at different levels in all tested tissues and throughout anther development.In vitro kinase assay showed OsLecRK-S.7 capable of autophosporylation.Mutation in s13283(E560K)and mutation of the conserved ATP binding site(K418E)both knocked out the kinase activity.Mass spectrometry showed Thr376,Ser378,Thr386,Thr403,and Thr657 to be the autophosphorylation sites.Mutation of individual autophosphorylation site affected the in vitro kinase activity to different degrees,but did not abolish the gene function in fertility complementation.oslecrk-s.7 mutant plant overexpressing OsLecRK-S.7 recovered male fertility but showed severe growth retardation with reduced number of tillers,and these phenotypes were abolished by E560K or K418E mutation.The results indicated that OsLecRK-S.7 was a key regulator of pollen development.
基金This work was supp orted by the Nationa l Key Research and Development Plan Program(2016YFD0100406 and 2016YFD0101801)National Natural Science Foundation of China(U1901203,31901532,and U1704232)+3 种基金Natural Science Foundation of Guangdong Province(2018B030308008)Shenzhen Commission on Innovation and Technology Programs(JCYJ20180507181837997)China Postdoctoral Science Foundation(2019M652938)Natural Science Foundation of Fujian Province(2017J01427)。
文摘Large-scale production of male sterile seeds can be achieved by introducing a fertility-restoration gene linked with a pollen-killer gene into a recessive male sterile mutant.We attempted to construct this system in rice by using a late-stage pollen-specific(LSP)promoter driving the expression of maizeα-amylase gene ZM-AA1.To obtain such promoters in rice,we conducted comparative RNA-seq analysis of mature pollen with meiosis anther,and compared this with the transcriptomic data of various tissues in the Rice Expression Database,resulting in 269 candidate LSP genes.Initial test of nine LSP genes showed that only the most active OsLSP3 promoter could drive ZM-AA1 to disrupt pollen.We then analyzed an additional 22 LSP genes and found 12 genes stronger than OsLSP3 in late-stage anthers.The promoters of OsLSP5 and OsLSP6 showing higher expression than OsLSP3 at stages 11 and 12 could drive ZM-AA1 to inactivate pollen,while the promoter of OsLSP4 showing higher expression at stage 12 only could not drive ZM-AA1 to disrupt pollen,suggesting that strong promoter activity at stage 11 was critical for pollen inactivation.The strong pollen-specific promoters identified in this study provided valuable tools for genetic engineering of rice male sterile system for hybrid rice production.
