Grafting is a plant propagation technique widely used in agriculture.A recent discovery of the capability of interfamily grafting in Nicotiana has expanded the potential combinations of grafting.In this study,we showe...Grafting is a plant propagation technique widely used in agriculture.A recent discovery of the capability of interfamily grafting in Nicotiana has expanded the potential combinations of grafting.In this study,we showed that xylem connection is essential for the achievement of interfamily grafting and investigated the molecular basis of xylem formation at the graft junction.Transcriptome and gene network analyses revealed gene modules for tracheary element(TE)formation during grafting that include genes associated with xylem cell differentiation and immune response.The reliability of the drawn network was validated by examining the role of the Nicotiana benthamiana XYLEM CYSTEINE PROTEASE(NbXCP)genes in TE formation during interfamily grafting.Promoter activities of NbXCP1 and NbXCP2 genes were found in differentiating TE cells in the stem and callus tissues at the graft junction.Analysis of a Nbxcp1;Nbxcp2 loss-of-function mutant indicated that NbXCPs control the timing of de novo TE formation at the graft junction.Moreover,grafts of the NbXCP1 overexpressor increased the scion growth rate as well as the fruit size.Thus,we identified gene modules for TE formation at the graft boundary and demonstrated potential ways to enhance Nicotiana interfamily grafting.展开更多
Since ancient times,humans have bred several plants that we rely on today.However,little is known about the divergence of most of these plants.In the present study,we investigated the divergence of Mibuna(Brassica rap...Since ancient times,humans have bred several plants that we rely on today.However,little is known about the divergence of most of these plants.In the present study,we investigated the divergence of Mibuna(Brassica rapa L.subsp.nipposinica L.H.Bailey),a traditional leafy vegetable in Kyoto(Japan),by combining genetic analysis and a survey of ancient literature.Mibuna is considered to have been bred 200 years ago from Mizuna,another traditional leafy vegetable in Kyoto.Mibuna has simple spatulate leaves,whereas Mizuna has characteristic serrated leaves.The quantitative trait loci(QTL)and gene expression analyses suggested that the downregulation of BrTCP15 expression contributed to the change in the leaf shape from serrated to simple spatulate.Interestingly,the SNP analysis indicated that the genomic region containing the BrTCP15 locus was transferred to Mibuna by introgression.Furthermore,we conducted a survey of ancient literature to reveal the divergence of Mibuna and found that hybridization between Mizuna and a simple-leaved turnip might have occurred in the past.Indeed,the genomic analysis of multiple turnip cultivars showed that one of the cultivars,Murasakihime,has almost the same sequence in the BrTCP15 region as Mibuna.These results suggest that the hybridization between Mizuna and turnip has resulted in the establishment of Mibuna.展开更多
In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA w...In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA within the phloem sap of several plant species. It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents, to further our understanding of how plants coordinate their developmental programs at the whole-plant level. In this study, we developed a strategy for the functional analysis of phloem-mobile mRNA by focusing on IAA transcripts, whose mobility has previously been reported in melon （Cucumis melo cv. Hale＇s Best Jumbo）. Indoleacetic acid （IAA） proteins are key transcriptional regulators of auxin signaling, and are involved in a broad range of developmental processes including root development. We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana. Micro-grafting experiments were used to confirm that these IAA transcripts, which are generated in vascular tissues of mature leaves, are then transported into the root system where they negatively regulate lateral root formation. Based on these findings, we present a model in which auxin distribution, in combination with phloem-mobile Aux/IAA transcripts, can determine the sites of auxin action.展开更多
Phase transition and floral induction in citrus requires several years of juvenility after germination.Such a long period of juvenility has been a major hindrance to its genetic improvement program.Studies have shown ...Phase transition and floral induction in citrus requires several years of juvenility after germination.Such a long period of juvenility has been a major hindrance to its genetic improvement program.Studies have shown that miR156 along with its downstream genes SQUAMOSA PROMOTER BINDING PROTEINS(SBP)and SBP-LIKE(SPL)mediate the phase transition and floral induction process in plants.Our current study has systematically analyzed SPLs in 15 different citrus-related species,systematically annotated them based on their close homology to their respective Arabidopsis orthologs,and confirmed the functional attributes of the selected members in floral precocity.The majority of the species harbored 15 SPLs.Their cis-element assessment suggested the involvement of the SPLs in diverse developmental and physiological processes in response to different biotic and abiotic cues.Among all,SPL5,SPL9,and SPL11 stood out as consistently differentially expressed SPLs in the adult and young tissues of different citrusrelated species.Independent overexpression of their F.hindsii orthologs(FhSPL5,FhSPL9,and FhSPL11)brought an enhanced expression of endogenous FLOWERING LOCUS T leading to the significantly precocious flowering in transgenic Arabidopsis lines.Future study of the genes in the citrus plant itself is expected to conclude the assessments made in the current study.展开更多
Plants are exposed to a variety of environmental stress,and starvation of inorganic phosphorus can be a major constraint in crop production.In plants,in response to phosphate deficiency in soil,miR399,a type of microR...Plants are exposed to a variety of environmental stress,and starvation of inorganic phosphorus can be a major constraint in crop production.In plants,in response to phosphate deficiency in soil,miR399,a type of microRNA(miRNA),is up-regulated.By detecting miR399,the early diagnosis of phosphorus deficiency stress in plants can be accomplished.However,general miRNA detection methods require complicated experimental manipulations.Therefore,simple and rapid miRNA detection methods are required for early plant nutritional diagnosis.展开更多
基金This work was supported by grants from the Japan Society for the Promotion of Science Grantsin-Aid for Scientific Research(20H03273,21H00368 and 21H05657 toMNand 22 K06181 to KK)Japan Science and Technology Agency(JPMJTR194G to MN)+1 种基金China Scholarship Council(CSCNo.201908050204 to CH).
文摘Grafting is a plant propagation technique widely used in agriculture.A recent discovery of the capability of interfamily grafting in Nicotiana has expanded the potential combinations of grafting.In this study,we showed that xylem connection is essential for the achievement of interfamily grafting and investigated the molecular basis of xylem formation at the graft junction.Transcriptome and gene network analyses revealed gene modules for tracheary element(TE)formation during grafting that include genes associated with xylem cell differentiation and immune response.The reliability of the drawn network was validated by examining the role of the Nicotiana benthamiana XYLEM CYSTEINE PROTEASE(NbXCP)genes in TE formation during interfamily grafting.Promoter activities of NbXCP1 and NbXCP2 genes were found in differentiating TE cells in the stem and callus tissues at the graft junction.Analysis of a Nbxcp1;Nbxcp2 loss-of-function mutant indicated that NbXCPs control the timing of de novo TE formation at the graft junction.Moreover,grafts of the NbXCP1 overexpressor increased the scion growth rate as well as the fruit size.Thus,we identified gene modules for TE formation at the graft boundary and demonstrated potential ways to enhance Nicotiana interfamily grafting.
基金This research was supported by grants in aid from the Japan Society for the Promotion of Science(KAKENHI grant numbers 16H01472 and 18H04787)the MEXT-Supported Program for the Strategic Research Foundation at Private Universities(grant number S1511023)from the Ministry of Education,Culture,Sports,Science,and Technology of Japan to S.K+2 种基金This work was also financially supported by the Sasakawa Scientific Research Grant from The Japan Science Society to Y.KThis study was supported by a Joint Usage/Research program of the Center for Ecological Research,Kyoto University,the Ministry of Education,Culture,Sports,Science,and Technology of Japan(MEXT)[Grant-in-Aid for Scientific Research on Innovative Areas(19H04870)]Research Funding for the Computational Software Supporting Program from Meiji University.
文摘Since ancient times,humans have bred several plants that we rely on today.However,little is known about the divergence of most of these plants.In the present study,we investigated the divergence of Mibuna(Brassica rapa L.subsp.nipposinica L.H.Bailey),a traditional leafy vegetable in Kyoto(Japan),by combining genetic analysis and a survey of ancient literature.Mibuna is considered to have been bred 200 years ago from Mizuna,another traditional leafy vegetable in Kyoto.Mibuna has simple spatulate leaves,whereas Mizuna has characteristic serrated leaves.The quantitative trait loci(QTL)and gene expression analyses suggested that the downregulation of BrTCP15 expression contributed to the change in the leaf shape from serrated to simple spatulate.Interestingly,the SNP analysis indicated that the genomic region containing the BrTCP15 locus was transferred to Mibuna by introgression.Furthermore,we conducted a survey of ancient literature to reveal the divergence of Mibuna and found that hybridization between Mizuna and a simple-leaved turnip might have occurred in the past.Indeed,the genomic analysis of multiple turnip cultivars showed that one of the cultivars,Murasakihime,has almost the same sequence in the BrTCP15 region as Mibuna.These results suggest that the hybridization between Mizuna and turnip has resulted in the establishment of Mibuna.
基金supported by a grant from the United States-Israel Binational Science Foundation(BSF 2007052,to W.J.L.and S.W.)by a Postdoctoral Fellowship for Research Abroad from the Japanese Society for the Promotion of Science(awarded to Michitaka Notaguchi).
文摘In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA within the phloem sap of several plant species. It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents, to further our understanding of how plants coordinate their developmental programs at the whole-plant level. In this study, we developed a strategy for the functional analysis of phloem-mobile mRNA by focusing on IAA transcripts, whose mobility has previously been reported in melon （Cucumis melo cv. Hale＇s Best Jumbo）. Indoleacetic acid （IAA） proteins are key transcriptional regulators of auxin signaling, and are involved in a broad range of developmental processes including root development. We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana. Micro-grafting experiments were used to confirm that these IAA transcripts, which are generated in vascular tissues of mature leaves, are then transported into the root system where they negatively regulate lateral root formation. Based on these findings, we present a model in which auxin distribution, in combination with phloem-mobile Aux/IAA transcripts, can determine the sites of auxin action.
基金Open access funding provided by Shanghai Jiao Tong Universitysupported by Major Special Projects and Key R&D Projects in Yunnan Province(NO.202102AE090054)+1 种基金the National Natural Science Foundation of China granted to Q.X.(numbers 31925034)Key project of Hubei provincial Natural Science Foundation(2021CFA017).
文摘Phase transition and floral induction in citrus requires several years of juvenility after germination.Such a long period of juvenility has been a major hindrance to its genetic improvement program.Studies have shown that miR156 along with its downstream genes SQUAMOSA PROMOTER BINDING PROTEINS(SBP)and SBP-LIKE(SPL)mediate the phase transition and floral induction process in plants.Our current study has systematically analyzed SPLs in 15 different citrus-related species,systematically annotated them based on their close homology to their respective Arabidopsis orthologs,and confirmed the functional attributes of the selected members in floral precocity.The majority of the species harbored 15 SPLs.Their cis-element assessment suggested the involvement of the SPLs in diverse developmental and physiological processes in response to different biotic and abiotic cues.Among all,SPL5,SPL9,and SPL11 stood out as consistently differentially expressed SPLs in the adult and young tissues of different citrusrelated species.Independent overexpression of their F.hindsii orthologs(FhSPL5,FhSPL9,and FhSPL11)brought an enhanced expression of endogenous FLOWERING LOCUS T leading to the significantly precocious flowering in transgenic Arabidopsis lines.Future study of the genes in the citrus plant itself is expected to conclude the assessments made in the current study.
基金supported by grants from the Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research(JP21H05657 to M.N.and JP22H04536 to M.H.)the Japan Science and Technology Agency(ERATO JPMJER1004 to T.H.and PRESTO 15665754,CREST JPMJCR15O2,SCORE 2110336,and START 2210365 to M.N.)the NARO Biooriented Technology Research Advancement Institution(SBIR 21488775 to M.N.).
文摘Plants are exposed to a variety of environmental stress,and starvation of inorganic phosphorus can be a major constraint in crop production.In plants,in response to phosphate deficiency in soil,miR399,a type of microRNA(miRNA),is up-regulated.By detecting miR399,the early diagnosis of phosphorus deficiency stress in plants can be accomplished.However,general miRNA detection methods require complicated experimental manipulations.Therefore,simple and rapid miRNA detection methods are required for early plant nutritional diagnosis.
