The Experts below are selected from a list of 1929 Experts worldwide ranked by ideXlab platform
Motoyuki Ashikari - One of the best experts on this subject based on the ideXlab platform.
-
eQTLs Regulating Transcript Variations Associated with Rapid Internode Elongation in Deepwater Rice.
Frontiers in plant science, 2017Co-Authors: Takeshi Kuroha, Motoyuki Ashikari, Keisuke Nagai, Hideshi Yasui, Yusuke Kurokawa, Yoshiaki Nagamura, Miyako Kusano, Atsushi FukushimaAbstract:To avoid low oxygen, oxygen deficiency or oxygen deprivation, deepwater rice cultivated in flood planes can develop elongated Internodes in response to submergence. Knowledge of the gene regulatory networks underlying rapid Internode Elongation is important for an understanding of the evolution and adaptation of major crops in response to flooding. To elucidate the genetic and molecular basis controlling their deepwater response we used microarrays and performed expression quantitative trait loci (eQTL) and phenotypic QTL (phQTL) analyses of Internode samples of 85 recombinant inbred line (RIL) populations of non-deepwater (Taichung 65)- and deepwater rice (Bhadua). After evaluating the phenotypic response of the RILs exposed to submergence, confirming the genotypes of the populations, and generating 188 genetic markers, we identified 10,047 significant eQTLs comprised of 2,902 cis-eQTLs and 7,145 trans-eQTLs and three significant eQTL hotspots on chromosomes 1, 4, and 12 that affect the expression of many genes. The hotspots on chromosomes 1 and 4 located at different position from phQTLs detected in this study and other previous studies. We then regarded the eQTL hotspots as key regulatory points to infer causal regulatory networks of deepwater response including rapid Internode Elongation. Our results suggest that the downstream regulation of the eQTL hotspots on chromosomes 1 and 4 is independent, and that the target genes are partially regulated by SNORKEL1 and SNORKEL2 genes (SK1/2), key ethylene response factors. Subsequent bioinformatic analyses, including gene ontology-based annotation and functional enrichment analysis and promoter enrichment analysis, contribute to enhance our understanding of SK1/2-dependent and independent pathways. One remarkable observation is that the functional categories related to photosynthesis and light signaling are significantly over-represented in the candidate target genes of SK1/2. The combined results of these investigations together with genetical genomics approaches using structured populations with a deepwater response are also discussed in the context of current molecular models concerning the rapid Internode Elongation in deepwater rice. This study provides new insights into the underlying genetic architecture of gene expression regulating the response to flooding in deepwater rice and will be an important community resource for analyses on the genetic basis of deepwater responses.
-
Gibberellin biosynthesis and signal transduction is essential for Internode Elongation in deepwater rice.
Plant Cell & Environment, 2014Co-Authors: Madoka Ayano, Hidemi Kitano, Takahiro Kani, Mikiko Kojima, Hitoshi Sakakibara, Takuya Kitaoka, Takeshi Kuroha, Rosalyn B. Angeles-shim, Keisuke Nagai, Motoyuki AshikariAbstract:Under flooded conditions, the leaves and Internodes of deepwater rice can elongate above the water surface to capture oxygen and prevent drowning. Our previous studies showed that three major quantitative trait loci (QTL) regulate deepwater-dependent Internode Elongation in deepwater rice. In this study, we investigated the age-dependent Internode Elongation in deepwater rice. We also investigated the relationship between deepwater-dependent Internode Elongation and the phytohormone gibberellin (GA) by physiological and genetic approach using a QTL pyramiding line (NIL-1 + 3 + 12). Deepwater rice did not show Internode Elongation before the sixth leaf stage under deepwater condition. Additionally, deepwater-dependent Internode Elongation occurred on the sixth and seventh Internodes during the sixth leaf stage. These results indicate that deepwater rice could not start Internode Elongation until the sixth leaf stage. Ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS) method for the phytohormone contents showed a deepwater-dependent GA1 and GA4 accumulation in deepwater rice. Additionally, a GA inhibitor abolished deepwater-dependent Internode Elongation in deepwater rice. On the contrary, GA feeding mimicked Internode Elongation under ordinary growth conditions. However, mutations in GA biosynthesis and signal transduction genes blocked deepwater-dependent Internode Elongation. These data suggested that GA biosynthesis and signal transduction are essential for deepwater-dependent Internode Elongation in deepwater rice.
-
QTL analysis of Internode Elongation in response to gibberellin in deepwater rice
AoB PLANTS, 2014Co-Authors: Keisuke Nagai, Takuya Kitaoka, Takeshi Kuroha, Rosalyn B. Angeles-shim, Yuma Kondo, Tomonori Noda, Hideshi Yasui, Atsushi Yoshimura, Motoyuki AshikariAbstract:Gibberellin (GA) is a plant hormone that has important roles in numerous plant developmental phases. Rice plants known as deepwater rice respond to flooding by elongating their Internodes to avoid anoxia. Previous studies re- ported that GA is essential for Internode Elongation in deepwater rice. Quantitative trait locus (QTL) analyses identified QTLs regulating Internode Elongation in response to deepwater conditions. However, the interaction between Internode Elongation and regulators of GA sensitivity in deepwater rice is unknown. In this study, we applied GA to recombinant inbred lines of T65 (non-deepwater rice) and Bhadua (deepwater rice), and performed a QTL analysis of Internode elong- ation in response to GA. GA-induced Internode Elongation was detected onlyin deepwater rice.Our QTLanalysis revealed two major QTLs on chromosomes 3 and 9 regulating total Internode length, lowest elongated Internode and number of elongated Internodes. Furthermore, the QTL on chromosome 3 acted as an enhancer of other QTLs (e.g. the QTL on chromosome 12). Nearly isogenic lines of deepwater rice carrying the QTL regions from chromosomes 3 and 12 of the deepwater rice C9285 showed Internode Elongation in response to GA. Thus, these QTLs may regulate GA responsiveness in deepwater rice. This study furthers our understanding of the mechanism of Internode Elongation in rice.
-
two novel qtls regulate Internode Elongation in deepwater rice during the early vegetative stage
Breeding Science, 2012Co-Authors: Keisuke Nagai, Madoka Ayano, Takeshi Kuroha, Hideshi Yasui, Atsushi Yoshimura, Yusuke Kurokawa, Rosalyn B Angelesshim, Junghyun Shim, Motoyuki AshikariAbstract:Deepwater rice possesses Internode Elongation ability to avoid drowning under deepwater conditions. Previous studies identified three QTLs regulating Internode Elongation ability on chromosomes 1, 3 and 12 using different populations. However, these QTLs only induce Internode Elongation in response to deepwater conditions from the 7-leaf stage and not during the early leaf stage. In this study, we detected two novel QTLs, qTIL2 and qTIL4 regulating deepwater response at the early leaf stage using an F2 population derived from the cross between NIL1-3-12 carrying the three QTLs regulating deepwater response in T65 (O. sativa ssp. japonica) genetic background and C9285 (O. sativa ssp. indica, deepwater rice). Plants of the BC2F2 population derived from NIL1-3-12/C9285 and the RILs of T65/Bhadua (O. sativa ssp. indica, deepwater rice) possessing these QTLs as well as the three QTLs previously identified also showed Internode Elongation during the early leaf stage. These results indicate that qTIL2 and qTIL4 regulate early Internode Elongation and function in coordination with the three major QTLs under deepwater conditions. The results presented here would not only help define the mechanism of deepwater response in rice but also contribute in the breeding of deepwater tolerant rice that is adapted to various water depths.
-
vacuolar proton pumps and aquaporins involved in rapid Internode Elongation of deepwater rice
Bioscience Biotechnology and Biochemistry, 2011Co-Authors: Yukari Muto, Motoyuki Ashikari, Yoko Hattori, Shoji Segami, Hidehiro Hayashi, Junko Sakurai, Mari Muraihatano, Masayoshi MaeshimaAbstract:Rapid growth of the submerged shoots of deepwater rice is essential for survival during the rainy season. We investigated changes in the expression of vacuolar H+-ATPase (V-ATPase), H+-pyrophosphatase (V-PPase), and aquaporins under submerged conditions. The amounts of vacuolar proton pumps, which support the active transport of ions into the vacuoles, were maintained on a membrane protein basis in the developing vacuoles. Among the six isogenes of V-PPase, OsVHP1;3 was markedly enhanced by submersion. The gene expression of efficient water channels, OsTIP1;1, OsTIP2;2, OsPIP1;1, OsPIP2;1, and OsPIP2;2, was markedly enhanced by submersion. The increase in aquaporin expression might support quick Elongation of Internodes. The mRNA levels of OsNIP2;2 and OsNIP3;1, which transport silicic and boric acids respectively, clearly decreased. The present study indicates that Internodes of deepwater rice upregulate vacuolar proton pumps and water channel aquaporins and downregulate aquaporins that allow permeation ...
Shouyi Chen - One of the best experts on this subject based on the ideXlab platform.
-
osglu1 a putative membrane bound endo 1 4 s d glucanase from rice affects plant Internode Elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell Elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the Internode Elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
-
osglu1 a putative membrane bound endo 1 4 beta d glucanase from rice affects plant Internode Elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell Elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the Internode Elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
Keisuke Nagai - One of the best experts on this subject based on the ideXlab platform.
-
antagonistic regulation of the gibberellic acid response during stem growth in rice
Nature, 2020Co-Authors: Keisuke Nagai, Yoshinao Mori, Shin Ishikawa, Tomoyuki Furuta, Rico Gamuyao, Yoko Niimi, Tokunori Hobo, Moyuri Fukuda, Mikiko KojimaAbstract:The size of plants is largely determined by growth of the stem. Stem Elongation is stimulated by gibberellic acid1–3. Here we show that Internode stem Elongation in rice is regulated antagonistically by an ‘accelerator’ and a ‘decelerator’ in concert with gibberellic acid. Expression of a gene we name ACCELERATOR OF Internode Elongation 1 (ACE1), which encodes a protein of unknown function, confers cells of the intercalary meristematic region with the competence for cell division, leading to Internode Elongation in the presence of gibberellic acid. By contrast, upregulation of DECELERATOR OF Internode Elongation 1 (DEC1), which encodes a zinc-finger transcription factor, suppresses Internode Elongation, whereas downregulation of DEC1 allows Internode Elongation. We also show that the mechanism of Internode Elongation that is mediated by ACE1 and DEC1 is conserved in the Gramineae family. Furthermore, an analysis of genetic diversity suggests that mutations in ACE1 and DEC1 have historically contributed to the selection of shorter plants in domesticated populations of rice to increase their resistance to lodging, and of taller plants in wild species of rice for adaptation to growth in deep water. Our identification of these antagonistic regulatory factors enhances our understanding of the gibberellic acid response as an additional mechanism that regulates Internode Elongation and environmental fitness, beyond biosynthesis and gibberellic acid signal transduction. Stem growth in rice is regulated by an accelerator gene and a decelerator gene in parallel with gibberellic acid, and the opposite selection of these genes has led to adaptations to different environments.
-
Ethylene-gibberellin signaling underlies adaptation of rice to periodic flooding
Science (New York N.Y.), 2018Co-Authors: Takeshi Kuroha, Takuya Kitaoka, Keisuke Nagai, Tomoyuki Furuta, Rico Gamuyao, Diane R. Wang, Masanari Nakamori, Keita Adachi, Anzu Minami, Yoshinao MoriAbstract:Most plants do poorly when flooded. Certain rice varieties, known as deepwater rice, survive periodic flooding and consequent oxygen deficiency by activating Internode growth of stems to keep above the water. Here, we identify the gibberellin biosynthesis gene, SD1 (SEMIDWARF1), whose loss-of-function allele catapulted the rice Green Revolution, as being responsible for submergence-induced Internode Elongation. When submerged, plants carrying the deepwater rice-specific SD1 haplotype amplify a signaling relay in which the SD1 gene is transcriptionally activated by an ethylene-responsive transcription factor, OsEIL1a. The SD1 protein directs increased synthesis of gibberellins, largely GA4, which promote Internode Elongation. Evolutionary analysis shows that the deepwater rice-specific haplotype was derived from standing variation in wild rice and selected for deepwater rice cultivation in Bangladesh.
-
eQTLs Regulating Transcript Variations Associated with Rapid Internode Elongation in Deepwater Rice.
Frontiers in plant science, 2017Co-Authors: Takeshi Kuroha, Motoyuki Ashikari, Keisuke Nagai, Hideshi Yasui, Yusuke Kurokawa, Yoshiaki Nagamura, Miyako Kusano, Atsushi FukushimaAbstract:To avoid low oxygen, oxygen deficiency or oxygen deprivation, deepwater rice cultivated in flood planes can develop elongated Internodes in response to submergence. Knowledge of the gene regulatory networks underlying rapid Internode Elongation is important for an understanding of the evolution and adaptation of major crops in response to flooding. To elucidate the genetic and molecular basis controlling their deepwater response we used microarrays and performed expression quantitative trait loci (eQTL) and phenotypic QTL (phQTL) analyses of Internode samples of 85 recombinant inbred line (RIL) populations of non-deepwater (Taichung 65)- and deepwater rice (Bhadua). After evaluating the phenotypic response of the RILs exposed to submergence, confirming the genotypes of the populations, and generating 188 genetic markers, we identified 10,047 significant eQTLs comprised of 2,902 cis-eQTLs and 7,145 trans-eQTLs and three significant eQTL hotspots on chromosomes 1, 4, and 12 that affect the expression of many genes. The hotspots on chromosomes 1 and 4 located at different position from phQTLs detected in this study and other previous studies. We then regarded the eQTL hotspots as key regulatory points to infer causal regulatory networks of deepwater response including rapid Internode Elongation. Our results suggest that the downstream regulation of the eQTL hotspots on chromosomes 1 and 4 is independent, and that the target genes are partially regulated by SNORKEL1 and SNORKEL2 genes (SK1/2), key ethylene response factors. Subsequent bioinformatic analyses, including gene ontology-based annotation and functional enrichment analysis and promoter enrichment analysis, contribute to enhance our understanding of SK1/2-dependent and independent pathways. One remarkable observation is that the functional categories related to photosynthesis and light signaling are significantly over-represented in the candidate target genes of SK1/2. The combined results of these investigations together with genetical genomics approaches using structured populations with a deepwater response are also discussed in the context of current molecular models concerning the rapid Internode Elongation in deepwater rice. This study provides new insights into the underlying genetic architecture of gene expression regulating the response to flooding in deepwater rice and will be an important community resource for analyses on the genetic basis of deepwater responses.
-
Gibberellin biosynthesis and signal transduction is essential for Internode Elongation in deepwater rice.
Plant Cell & Environment, 2014Co-Authors: Madoka Ayano, Hidemi Kitano, Takahiro Kani, Mikiko Kojima, Hitoshi Sakakibara, Takuya Kitaoka, Takeshi Kuroha, Rosalyn B. Angeles-shim, Keisuke Nagai, Motoyuki AshikariAbstract:Under flooded conditions, the leaves and Internodes of deepwater rice can elongate above the water surface to capture oxygen and prevent drowning. Our previous studies showed that three major quantitative trait loci (QTL) regulate deepwater-dependent Internode Elongation in deepwater rice. In this study, we investigated the age-dependent Internode Elongation in deepwater rice. We also investigated the relationship between deepwater-dependent Internode Elongation and the phytohormone gibberellin (GA) by physiological and genetic approach using a QTL pyramiding line (NIL-1 + 3 + 12). Deepwater rice did not show Internode Elongation before the sixth leaf stage under deepwater condition. Additionally, deepwater-dependent Internode Elongation occurred on the sixth and seventh Internodes during the sixth leaf stage. These results indicate that deepwater rice could not start Internode Elongation until the sixth leaf stage. Ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS) method for the phytohormone contents showed a deepwater-dependent GA1 and GA4 accumulation in deepwater rice. Additionally, a GA inhibitor abolished deepwater-dependent Internode Elongation in deepwater rice. On the contrary, GA feeding mimicked Internode Elongation under ordinary growth conditions. However, mutations in GA biosynthesis and signal transduction genes blocked deepwater-dependent Internode Elongation. These data suggested that GA biosynthesis and signal transduction are essential for deepwater-dependent Internode Elongation in deepwater rice.
-
QTL analysis of Internode Elongation in response to gibberellin in deepwater rice
AoB PLANTS, 2014Co-Authors: Keisuke Nagai, Takuya Kitaoka, Takeshi Kuroha, Rosalyn B. Angeles-shim, Yuma Kondo, Tomonori Noda, Hideshi Yasui, Atsushi Yoshimura, Motoyuki AshikariAbstract:Gibberellin (GA) is a plant hormone that has important roles in numerous plant developmental phases. Rice plants known as deepwater rice respond to flooding by elongating their Internodes to avoid anoxia. Previous studies re- ported that GA is essential for Internode Elongation in deepwater rice. Quantitative trait locus (QTL) analyses identified QTLs regulating Internode Elongation in response to deepwater conditions. However, the interaction between Internode Elongation and regulators of GA sensitivity in deepwater rice is unknown. In this study, we applied GA to recombinant inbred lines of T65 (non-deepwater rice) and Bhadua (deepwater rice), and performed a QTL analysis of Internode elong- ation in response to GA. GA-induced Internode Elongation was detected onlyin deepwater rice.Our QTLanalysis revealed two major QTLs on chromosomes 3 and 9 regulating total Internode length, lowest elongated Internode and number of elongated Internodes. Furthermore, the QTL on chromosome 3 acted as an enhancer of other QTLs (e.g. the QTL on chromosome 12). Nearly isogenic lines of deepwater rice carrying the QTL regions from chromosomes 3 and 12 of the deepwater rice C9285 showed Internode Elongation in response to GA. Thus, these QTLs may regulate GA responsiveness in deepwater rice. This study furthers our understanding of the mechanism of Internode Elongation in rice.
Hidemi Kitano - One of the best experts on this subject based on the ideXlab platform.
-
Gibberellin biosynthesis and signal transduction is essential for Internode Elongation in deepwater rice.
Plant Cell & Environment, 2014Co-Authors: Madoka Ayano, Hidemi Kitano, Takahiro Kani, Mikiko Kojima, Hitoshi Sakakibara, Takuya Kitaoka, Takeshi Kuroha, Rosalyn B. Angeles-shim, Keisuke Nagai, Motoyuki AshikariAbstract:Under flooded conditions, the leaves and Internodes of deepwater rice can elongate above the water surface to capture oxygen and prevent drowning. Our previous studies showed that three major quantitative trait loci (QTL) regulate deepwater-dependent Internode Elongation in deepwater rice. In this study, we investigated the age-dependent Internode Elongation in deepwater rice. We also investigated the relationship between deepwater-dependent Internode Elongation and the phytohormone gibberellin (GA) by physiological and genetic approach using a QTL pyramiding line (NIL-1 + 3 + 12). Deepwater rice did not show Internode Elongation before the sixth leaf stage under deepwater condition. Additionally, deepwater-dependent Internode Elongation occurred on the sixth and seventh Internodes during the sixth leaf stage. These results indicate that deepwater rice could not start Internode Elongation until the sixth leaf stage. Ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS) method for the phytohormone contents showed a deepwater-dependent GA1 and GA4 accumulation in deepwater rice. Additionally, a GA inhibitor abolished deepwater-dependent Internode Elongation in deepwater rice. On the contrary, GA feeding mimicked Internode Elongation under ordinary growth conditions. However, mutations in GA biosynthesis and signal transduction genes blocked deepwater-dependent Internode Elongation. These data suggested that GA biosynthesis and signal transduction are essential for deepwater-dependent Internode Elongation in deepwater rice.
-
the ethylene response factors snorkel1 and snorkel2 allow rice to adapt to deep water
Nature, 2009Co-Authors: Yoko Hattori, Hitoshi Sakakibara, Keisuke Nagai, Atsushi Yoshimura, Shizuka Furukawa, Xianjun Song, Ritsuko Kawano, Takashi Matsumoto, Jianzhong Wu, Hidemi KitanoAbstract:Monsoon season floods in Asia can cause widespread devastation of rice crops. Some strains of rice have adapted to this environmental stress by developing the ability to undergo rapid stem Elongation. Normally this type of rice grows to about a metre high, but when flooding occurs, the stem undergoes rapid and dramatic Internode Elongation and can grow to several metres, according to the water level. Hattori et al. have identified the genes that trigger Internode Elongation in deepwater rice, called SNORKEL1 and SNORKEL2. They code for transcription factors that regulate signalling of the gaseous phytohormone, ethylene. The introduction of these genes into high yield cultivars could boost rice production in flood prone areas. In Asia, flooding during the monsoon season can result in widespread devastation of rice crops. Deepwater rice has evolved and adapted to flooding by acquiring the ability to significantly elongate its Internodes. The molecular mechanism of this deepwater response is now identified as being dependent on the genes SNORKEL1 and SNORKEL2, which trigger deepwater response by encoding ethylene response factors involved in ethylene signalling. Living organisms must acquire new biological functions to adapt to changing and hostile environments. Deepwater rice has evolved and adapted to flooding by acquiring the ability to significantly elongate its Internodes, which have hollow structures and function as snorkels to allow gas exchange with the atmosphere, and thus prevent drowning1,2,3. Many physiological studies have shown that the phytohormones ethylene, gibberellin and abscisic acid are involved in this response4,5,6,7,8, but the gene(s) responsible for this trait has not been identified. Here we show the molecular mechanism of deepwater response through the identification of the genes SNORKEL1 and SNORKEL2, which trigger deepwater response by encoding ethylene response factors involved in ethylene signalling. Under deepwater conditions, ethylene accumulates in the plant and induces expression of these two genes. The products of SNORKEL1 and SNORKEL2 then trigger remarkable Internode Elongation via gibberellin. We also demonstrate that the introduction of three quantitative trait loci from deepwater rice into non-deepwater rice enabled the latter to become deepwater rice. This discovery will contribute to rice breeding in lowland areas that are frequently flooded during the rainy season.
-
Mapping of three QTLs that regulate Internode Elongation in deepwater rice
Breeding Science, 2008Co-Authors: Yoko Hattori, Hidemi Kitano, Makoto Matsuoka, Keisuke Nagai, Hitoshi Mori, Motoyuki AshikariAbstract:The Internodes of deepwater rice can elongate in response to rises in water level. This unique character allows deepwater rice to survive severe flooding during the monsoon season in South and Southeast Asia. Our previous quantitative trait locus (QTL) analysis of a deepwater rice cultivar (Oryza sativa) detected QTLs on chromosomes 1, 3 and 12. In this study, we produced three nearly isogenic lines (NILs) possessing each of the three QTLs by backcross introduction of each chromosomal region into a non-deepwater rice cultivar. The NILs showed Internode Elongation under deepwater conditions, and we were able to demonstrate the existence of the QTLs and to evaluate the effect of each QTL. Using progenies of the NILs, we mapped all QTLs between molecular markers. Comparison of the location of the most effective QTL between the rice cultivar (O. sativa) and a wild rice species (O. rufipogon) indicated that the QTL on chromosome 12 is common and is the most important QTL for Internode Elongation in deepwater condition.
-
A Major QTL Confers Rapid Internode Elongation in Response to Water Rise in Deepwater Rice
Breeding Science, 2007Co-Authors: Yoko Hattori, Hidemi Kitano, Makoto Matsuoka, Kotaro Miura, Kenji Asano, Eiji Yamamoto, Hitoshi Mori, Motoyuki AshikariAbstract:To avoid drowning under flooded conditions, deepwater rice responds to rising water level by rapid Internode Elongation. Quantitative trait locus (QTL) analysis, using a deepwater rice cultivar (Oryza sativa) and a wild rice species (O. rufipogon) with deepwater characteristics, revealed the presence of major QTLs (qTIL12, qNEI12 and qLEI12) in a common chromosomal region that regulates Internode Elongation. Genetic analysis revealed that a QTL inherited in a dominant manner, was located on the long arm of chromosome 12. A nearly isogenic line (NIL), produced by backcross introduction of a chromosome fragment carrying this major QTL into non-deepwater rice, exhibited a dramatic Internode Elongation in response to water rise. This indicates that the difference between deepwater rice and non-deepwater rice is associated with the presence of the QTL, and that this sequence is sufficient to confer deepwater characteristics. Although deepwater rice and non-deepwater rice share a common machinery for Internode Elongation; non-deepwater rice cannot activate the machinery in response to flooding, unlike deepwater rice which harbors this major QTL.
-
rice dwarf mutant d1 which is defective in the α subunit of the heterotrimeric g protein affects gibberellin signal transduction
Proceedings of the National Academy of Sciences of the United States of America, 2000Co-Authors: Miyako Ueguchitanaka, Yukiko Fujisawa, Masatomo Kobayashi, Yukimoto Iwasaki, Hidemi Kitano, Motoyuki Ashikari, Makoto MatsuokaAbstract:Previously, we reported that the rice dwarf mutant, d1, is defective in the α subunit of the heterotrimeric G protein (Gα). In the present study, gibberellin (GA) signaling in d1 and the role of the Gα protein in the GA-signaling pathway were investigated. Compared with the wild type, GA induction of α-amylase activity in aleurone cells of d1 was greatly reduced. Relative to the wild type, the GA3-treated aleurone layer of d1 had lower expression of Ramy1A, which encodes α-amylase, and OsGAMYB, which encodes a GA-inducible transcriptional factor, and no increase in expression of Ca2 +-ATPase. However, in the presence of high GA concentrations, α-amylase induction occurred even in d1. The GA sensitivity of second leaf sheath Elongation in d1 was similar to that of the wild type in terms of dose responsiveness, but the response of Internode Elongation to GA was much lower in d1. Furthermore, Os20ox expression was up-regulated, and the GA content was elevated in the stunted Internodes of d1. All these results suggest that d1 affects a part of the GA-signaling pathway, namely the induction of α-amylase in the aleurone layer and Internode Elongation. In addition, a double mutant between d1 and another GA-signaling mutant, slr, revealed that SLR is epistatic to the D1, supporting that the Gα protein is involved in GA signaling. However, the data also provide evidence for the presence of an alternative GA-signaling pathway that does not involve the Gα protein. It is proposed that GA signaling via the Gα protein may be more sensitive than that of the alternative pathway, as indicated by the low GA responsiveness of this Gα-independent pathway.
Hualin Zhou - One of the best experts on this subject based on the ideXlab platform.
-
osglu1 a putative membrane bound endo 1 4 s d glucanase from rice affects plant Internode Elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell Elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the Internode Elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
-
osglu1 a putative membrane bound endo 1 4 beta d glucanase from rice affects plant Internode Elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell Elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the Internode Elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
