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Xu F, Tang J, Gao S, Cheng X, Du L, Chu C. Control of rice pre-harvest sprouting by glutaredoxin-mediated abscisic acid signaling. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 100:1036-1051. [PMID: 31436865 DOI: 10.1111/tpj.14501] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 07/27/2019] [Accepted: 08/07/2019] [Indexed: 05/18/2023]
Abstract
Pre-harvest sprouting (PHS) is one of the major problems in cereal production worldwide, which causes significant losses of both yield and quality; however, the molecular mechanism underlying PHS remains largely unknown. Here, we identified a dominant PHS mutant phs9-D. The corresponding gene PHS9 encodes a higher plant unique CC-type glutaredoxin and is specifically expressed in the embryo at the late embryogenesis stage, implying that PHS9 plays some roles in the late stage of seed development. Yeast two-hybrid screening showed that PHS9 could interact with OsGAP, which is an interaction partner of the abscicic acid (ABA) receptor OsRCAR1. PHS9- or OsGAP overexpression plants showed reduced ABA sensitivity in seed germination, whereas PHS9 or OsGAP knock-out mutant plants showed increased ABA sensitivity in seed germination, suggesting that PHS9 and OsGAP acted as negative regulators in ABA signaling during seed germination. Interestingly, the germination of PHS9 and OsGAP overexpression or knock-out plant seeds was weakly promoted by H2 O2 , implying that PHS9 and OsGAP could affect reactive oxygen species (ROS) signaling during seed germination. These results indicate that PHS9 plays an important role in the regulation of rice PHS through the integration of ROS signaling and ABA signaling.
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Affiliation(s)
- Fan Xu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Jiuyou Tang
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Shaopei Gao
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Xi Cheng
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Lin Du
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
| | - Chengcai Chu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
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Xiao Y, Liu D, Zhang G, Gao S, Liu L, Xu F, Che R, Wang Y, Tong H, Chu C. Big Grain3, encoding a purine permease, regulates grain size via modulating cytokinin transport in rice. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2019; 61:581-597. [PMID: 30267474 DOI: 10.1111/jipb.12727] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 09/21/2018] [Indexed: 05/20/2023]
Abstract
Grain size is an important agronomic trait affecting grain yield, but the underlying molecular mechanisms remain to be elucidated. Here, we isolated a dominant mutant, big grain3 (bg3-D), which exhibits a remarkable increase of grain size caused by activation of the PURINE PERMEASE gene, OsPUP4. BG3/OsPUP4 is predominantly expressed in vascular tissues and is specifically suppressed by exogenous cytokinin application. Hormone profiling revealed that the distribution of different cytokinin forms, in roots and shoots of the bg3-D mutant, is altered. Quantitative reverse transcription-PCR (qRT-PCR) analysis indicated that expression of rice cytokinin type-A RESPONSE REGULATOR (OsRR) genes is enhanced in the roots of the bg3-D mutant. These results suggest that OsPUP4 might contribute to the long-distance transport of cytokinin, by reinforcing cytokinin loading into vascular bundle cells. Furthermore, plants overexpressing OsPUP7, the closest homolog of OsPUP4, also exhibited a similar phenotype to the bg3-D mutant. Interestingly, subcellular localization demonstrated that OsPUP4 was localized on the plasma membrane, whereas OsPUP7 was localized to the endoplasmic reticulum. Based on these findings, we propose that OsPUP4 and OsPUP7 function in a linear pathway to direct cytokinin cell-to-cell transport, affecting both its long-distance movement and local allocation.
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Affiliation(s)
- Yunhua Xiao
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Dapu Liu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Guoxia Zhang
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Shaopei Gao
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Linchuan Liu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Fan Xu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Ronghui Che
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Yiqin Wang
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
| | - Hongning Tong
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, the Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Chengcai Chu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China
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Fraiture MA, Herman P, Taverniers I, De Loose M, Deforce D, Roosens NH. Current and new approaches in GMO detection: challenges and solutions. BIOMED RESEARCH INTERNATIONAL 2015; 2015:392872. [PMID: 26550567 PMCID: PMC4624882 DOI: 10.1155/2015/392872] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 09/07/2015] [Indexed: 11/17/2022]
Abstract
In many countries, genetically modified organisms (GMO) legislations have been established in order to guarantee the traceability of food/feed products on the market and to protect the consumer freedom of choice. Therefore, several GMO detection strategies, mainly based on DNA, have been developed to implement these legislations. Due to its numerous advantages, the quantitative PCR (qPCR) is the method of choice for the enforcement laboratories in GMO routine analysis. However, given the increasing number and diversity of GMO developed and put on the market around the world, some technical hurdles could be encountered with the qPCR technology, mainly owing to its inherent properties. To address these challenges, alternative GMO detection methods have been developed, allowing faster detections of single GM target (e.g., loop-mediated isothermal amplification), simultaneous detections of multiple GM targets (e.g., PCR capillary gel electrophoresis, microarray, and Luminex), more accurate quantification of GM targets (e.g., digital PCR), or characterization of partially known (e.g., DNA walking and Next Generation Sequencing (NGS)) or unknown (e.g., NGS) GMO. The benefits and drawbacks of these methods are discussed in this review.
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Affiliation(s)
- Marie-Alice Fraiture
- Platform of Biotechnology and Molecular Biology (PBB) and Biosafety and Biotechnology Unit (SBB), Scientific Institute of Public Health (WIV-ISP), J. Wytsmanstraat 14, 1050 Brussels, Belgium
- Technology and Food Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Burg. Van Gansberghelaan 115, Bus 1, 9820 Merelbeke, Belgium
- Laboratory of Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Philippe Herman
- Platform of Biotechnology and Molecular Biology (PBB) and Biosafety and Biotechnology Unit (SBB), Scientific Institute of Public Health (WIV-ISP), J. Wytsmanstraat 14, 1050 Brussels, Belgium
| | - Isabel Taverniers
- Technology and Food Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Burg. Van Gansberghelaan 115, Bus 1, 9820 Merelbeke, Belgium
| | - Marc De Loose
- Technology and Food Sciences Unit, Institute for Agricultural and Fisheries Research (ILVO), Burg. Van Gansberghelaan 115, Bus 1, 9820 Merelbeke, Belgium
- Department of Plant Biotechnology and Bioinformatics, Faculty of Sciences, Ghent University, Technologiepark 927, 9052 Ghent, Belgium
| | - Dieter Deforce
- Laboratory of Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium
| | - Nancy H. Roosens
- Platform of Biotechnology and Molecular Biology (PBB) and Biosafety and Biotechnology Unit (SBB), Scientific Institute of Public Health (WIV-ISP), J. Wytsmanstraat 14, 1050 Brussels, Belgium
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Activation of Big Grain1 significantly improves grain size by regulating auxin transport in rice. Proc Natl Acad Sci U S A 2015; 112:11102-7. [PMID: 26283354 DOI: 10.1073/pnas.1512748112] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Grain size is one of the key factors determining grain yield. However, it remains largely unknown how grain size is regulated by developmental signals. Here, we report the identification and characterization of a dominant mutant big grain1 (Bg1-D) that shows an extra-large grain phenotype from our rice T-DNA insertion population. Overexpression of BG1 leads to significantly increased grain size, and the severe lines exhibit obviously perturbed gravitropism. In addition, the mutant has increased sensitivities to both auxin and N-1-naphthylphthalamic acid, an auxin transport inhibitor, whereas knockdown of BG1 results in decreased sensitivities and smaller grains. Moreover, BG1 is specifically induced by auxin treatment, preferentially expresses in the vascular tissue of culms and young panicles, and encodes a novel membrane-localized protein, strongly suggesting its role in regulating auxin transport. Consistent with this finding, the mutant has increased auxin basipetal transport and altered auxin distribution, whereas the knockdown plants have decreased auxin transport. Manipulation of BG1 in both rice and Arabidopsis can enhance plant biomass, seed weight, and yield. Taking these data together, we identify a novel positive regulator of auxin response and transport in a crop plant and demonstrate its role in regulating grain size, thus illuminating a new strategy to improve plant productivity.
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Xu F, Fang J, Ou S, Gao S, Zhang F, Du L, Xiao Y, Wang H, Sun X, Chu J, Wang G, Chu C. Variations in CYP78A13 coding region influence grain size and yield in rice. PLANT, CELL & ENVIRONMENT 2015; 38:800-11. [PMID: 25255828 DOI: 10.1111/pce.12452] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/11/2014] [Accepted: 09/15/2014] [Indexed: 05/21/2023]
Abstract
Grain size is one of the most important determinants of crop yield in cereals. Here, we identified a dominant mutant, big grain2 (bg2-D) from our enhancer-trapping population. Genetic analysis and SiteFinding PCR (polymerase chain reaction) revealed that BG2 encodes a cytochrome P450, OsCYP78A13. Sequence search revealed that CYP78A13 has a paralogue Grain Length 3.2 (GL3.2, LOC_Os03g30420) in rice with distinct expression patterns, analysis of transgenic plants harbouring either CYP78A13 or GL3.2 showed that both can promote grain growth. Sequence polymorphism analysis with 1529 rice varieties showed that the nucleotide diversity at CYP78A13 gene body and the 20 kb flanking region in the indica varieties were markedly higher than those in japonica varieties. Further, comparison of the genomic sequence of CYP78A13 in the japonica cultivar Nipponbare and the indica cultivar 9311 showed that there were three InDels in the promoter region and eight SNPs (single nucleotide polymorphism) in its coding sequence. Detailed examination of the transgenic plants with chimaeric constructs suggested that variation in CYP78A13 coding region is responsible for the variation of grain yield. Taken together, our results suggest that the variations in CYP78A13 in the indica varieties hold potential in rice breeding for application of grain yield improvement.
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Affiliation(s)
- Fan Xu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China; University of the Chinese Academy of Sciences, Yuquan Road, Beijing, 100039, China
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Gao S, Fang J, Xu F, Wang W, Sun X, Chu J, Cai B, Feng Y, Chu C. CYTOKININ OXIDASE/DEHYDROGENASE4 Integrates Cytokinin and Auxin Signaling to Control Rice Crown Root Formation. PLANT PHYSIOLOGY 2014; 165:1035-1046. [PMID: 24808099 PMCID: PMC4081320 DOI: 10.1104/pp.114.238584] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 05/03/2014] [Indexed: 05/17/2023]
Abstract
Crown roots constitute the majority of the rice (Oryza sativa) root system and play an important role in rice growth and development. However, the molecular mechanism of crown root formation in rice is not well understood. Here, we characterized a rice dominant mutant, root enhancer1 (ren1-D), which was observed to exhibit a more robust root system, increased crown root number, and reduced plant height. Molecular and genetic analyses revealed that these phenotypes are caused by the activation of a cytokinin oxidase/dehydrogenase (CKX) family gene, OsCKX4. Subcellular localization demonstrated that OsCKX4 is a cytosolic isoform of CKX. OsCKX4 is predominantly expressed in leaf blades and roots. It is the dominant CKX, preferentially expressed in the shoot base where crown root primordia are produced, underlining its role in root initiation. OsCKX4 is induced by exogenous auxin and cytokinin in the roots. Furthermore, one-hybrid assays revealed that OsCKX4 is a direct binding target of both the auxin response factor OsARF25 and the cytokinin response regulators OsRR2 and OsRR3. Overexpression and RNA interference of OsCKX4 confirmed that OsCKX4 plays a positive role in crown root formation. Moreover, expression analysis revealed a significant alteration in the expression of auxin-related genes in the ren1-D mutants, indicating that the OsCKX4 mediates crown root development by integrating the interaction between cytokinin and auxin. Transgenic plants harboring OsCKX4 under the control of the root-specific promoter RCc3 displayed enhanced root development without affecting their shoot parts, suggesting that this strategy could be a powerful tool in rice root engineering.
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Affiliation(s)
- Shaopei Gao
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Jun Fang
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Fan Xu
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Wei Wang
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Xiaohong Sun
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Jinfang Chu
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Baodong Cai
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Yuqi Feng
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
| | - Chengcai Chu
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China (S.G.);State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China (S.G., J.F., F.X., W.W., X.S., J.C., C.C.); andKey Laboratory of Analytical Chemistry for Biology and Medicine of the Ministry of Education, Department of Chemistry, Wuhan University, Wuhan 430072, China (B.C., Y.F.)
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Guo X, Hou X, Fang J, Wei P, Xu B, Chen M, Feng Y, Chu C. The rice GERMINATION DEFECTIVE 1, encoding a B3 domain transcriptional repressor, regulates seed germination and seedling development by integrating GA and carbohydrate metabolism. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 75:403-16. [PMID: 23581288 PMCID: PMC3813988 DOI: 10.1111/tpj.12209] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 04/08/2013] [Accepted: 04/11/2013] [Indexed: 05/19/2023]
Abstract
It has been shown that seed development is regulated by a network of transcription factors in Arabidopsis including LEC1 (LEAFY COTYLEDON1), L1L (LEC1-like) and the B3 domain factors LEC2, FUS3 (FUSCA3) and ABI3 (ABA-INSENSITIVE3); however, molecular and genetic regulation of seed development in cereals is poorly understood. To understand seed development and seed germination in cereals, a large-scale screen was performed using our T-DNA mutant population, and a mutant germination-defective1 (gd1) was identified. In addition to the severe germination defect, the gd1 mutant also shows a dwarf phenotype and abnormal flower development. Molecular and biochemical analyses revealed that GD1 encodes a B3 domain-containing transcription factor with repression activity. Consistent with the dwarf phenotype of gd1, expression of the gibberelic acid (GA) inactivation gene OsGA2ox3 is increased dramatically, accompanied by reduced expression of GA biosynthetic genes including OsGA20ox1, OsGA20ox2 and OsGA3ox2 in gd1, resulting in a decreased endogenous GA₄ level. Exogenous application of GA not only induced GD1 expression, but also partially rescued the dwarf phenotype of gd1. Furthermore, GD1 binds to the promoter of OsLFL1, a LEC2/FUS3-like gene of rice, via an RY element, leading to significant up-regulation of OsLFL1 and a large subset of seed maturation genes in the gd1 mutant. Plants over-expressing OsLFL1 partly mimic the gd1 mutant. In addition, expression of GD1 was induced under sugar treatment, and the contents of starch and soluble sugar are altered in the gd1 mutant. These data indicate that GD1 participates directly or indirectly in regulating GA and carbohydrate homeostasis, and further regulates rice seed germination and seedling development.
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Affiliation(s)
- Xiaoli Guo
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijing, 100101, China
| | - Xiaomei Hou
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijing, 100101, China
- Graduate University of the Chinese Academy of SciencesBeijing, 100049, China
| | - Jun Fang
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijing, 100101, China
- For correspondence (e-mail or )
| | - Piwei Wei
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijing, 100101, China
| | - Bo Xu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijing, 100101, China
- Graduate University of the Chinese Academy of SciencesBeijing, 100049, China
| | - Mingluan Chen
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) Department of Chemistry, Wuhan UniversityWuhan, 430072, China
| | - Yuqi Feng
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) Department of Chemistry, Wuhan UniversityWuhan, 430072, China
| | - Chengcai Chu
- State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of SciencesBeijing, 100101, China
- For correspondence (e-mail or )
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