1
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Wang J, Guo X, Chen Y, Liu T, Zhu J, Xu S, Vierling E. Maternal nitric oxide homeostasis impacts female gametophyte development under optimal and stress conditions. THE PLANT CELL 2024; 36:2201-2218. [PMID: 38376990 PMCID: PMC11132896 DOI: 10.1093/plcell/koae043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/08/2024] [Accepted: 01/08/2023] [Indexed: 02/22/2024]
Abstract
In adverse environments, the number of fertilizable female gametophytes (FGs) in plants is reduced, leading to increased survival of the remaining offspring. How the maternal plant perceives internal growth cues and external stress conditions to alter FG development remains largely unknown. We report that homeostasis of the stress signaling molecule nitric oxide (NO) plays a key role in controlling FG development under both optimal and stress conditions. NO homeostasis is precisely regulated by S-nitrosoglutathione reductase (GSNOR). Prior to fertilization, GSNOR protein is exclusively accumulated in sporophytic tissues and indirectly controls FG development in Arabidopsis (Arabidopsis thaliana). In GSNOR null mutants, NO species accumulated in the degenerating sporophytic nucellus, and auxin efflux into the developing FG was restricted, which inhibited FG development, resulting in reduced fertility. Importantly, restoring GSNOR expression in maternal, but not gametophytic tissues, or increasing auxin efflux substrate significantly increased the proportion of normal FGs and fertility. Furthermore, GSNOR overexpression or added auxin efflux substrate increased fertility under drought and salt stress. These data indicate that NO homeostasis is critical to normal auxin transport and maternal control of FG development, which in turn determine seed yield. Understanding this aspect of fertility control could contribute to mediating yield loss under adverse conditions.
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Affiliation(s)
- Junzhe Wang
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
- Hainan Yazhou Bay Seed Laboratory, Yazhou, Sanya 572025, China
| | - Xiaolong Guo
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yijin Chen
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Tianxiang Liu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Jianchu Zhu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Shengbao Xu
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Elizabeth Vierling
- Department of Biochemistry & Molecular Biology, University of Massachusetts, Amherst, MA 01003, USA
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2
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Zhong S, Zhao P, Peng X, Li HJ, Duan Q, Cheung AY. From gametes to zygote: Mechanistic advances and emerging possibilities in plant reproduction. PLANT PHYSIOLOGY 2024; 195:4-35. [PMID: 38431529 PMCID: PMC11060694 DOI: 10.1093/plphys/kiae125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 02/13/2024] [Accepted: 02/13/2024] [Indexed: 03/05/2024]
Affiliation(s)
- Sheng Zhong
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, New Cornerstone Science Laboratory, College of Life Sciences, Peking University, Beijing 100871, China
| | - Peng Zhao
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Xiongbo Peng
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
- Hubei Hongshan Laboratory, Wuhan 430070, China
| | - Hong-Ju Li
- Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Center for Molecular Agrobiology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qiaohong Duan
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an, Shandong 271018, China
| | - Alice Y Cheung
- Department of Biochemistry and Molecular Biology, Molecular and Cellular Biology Program, Plant Biology Graduate Program, University of Massachusetts, Amherst, MA 01003, USA
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3
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Dan J, Xia Y, Wang Y, Zhan Y, Tian J, Tang N, Deng H, Cao M. One-line hybrid rice with high-efficiency synthetic apomixis and near-normal fertility. PLANT CELL REPORTS 2024; 43:79. [PMID: 38400858 PMCID: PMC10894110 DOI: 10.1007/s00299-024-03154-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 01/09/2024] [Indexed: 02/26/2024]
Abstract
KEY MESSAGE High-frequency clonal seeds and near-normal fertility were obtained by engineering synthetic apomixis in hybrid rice. The one-line strategy, with the advantage of unnecessary seed production, is the final stage for the hybrid rice development and can be achieved through the fixation of heterosis via artificially inducing apomixis. Recently, synthetic apomixis has been generated in rice by combining MiMe (Mitosis instead of Meiosis) with either the ectopic expression of BABY BOOM (BBM1 or BBM4) or mutation of MATRILINEAL (MTL), resulting in over 95.00% of clonal seeds. However, the frequency of clonal seeds was only 29.20% when AtDD45 promoter was used to drive BBM1. In addition, achieving both a high frequency of clonal seeds and near-normal fertility simultaneously had been elusive in earlier strategies. In this study, using AtDD45 promoter to drive BBM1 expression in combination with the MiMe mutant resulted in the apomixis frequency as high as 98.70%. Even more, employing fusion promoters (AtMYB98_AtDD1_OsECA1-like1) to drive WUS expression in combination with pAtDD45:BBM1 and MiMe could produce clonal seeds at rates of up to 98.21%, the highest seed setting rate reached to 83.67%. Multiple-embryos were observed in clonal lines at a frequency ranging from 3.37% to 60.99%. Transmission of the high frequency of apomixis through skipped generations (atavism) was identified in two clonal lines, even though it remained stable in the majority of clonal lines. These findings significantly advance the pursuit of fixed heterosis in rice through synthetic apomixis, edging closer to its agricultural application.
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Affiliation(s)
- Junhao Dan
- Long Ping Branch, College of Biology, Hunan University, Changsha, 410082, People's Republic of China
| | - Yumei Xia
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, 410125, People's Republic of China
| | - Yao Wang
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, People's Republic of China
| | - Yijie Zhan
- Long Ping Branch, College of Biology, Hunan University, Changsha, 410082, People's Republic of China
| | - Junyou Tian
- Long Ping Branch, College of Biology, Hunan University, Changsha, 410082, People's Republic of China
| | - Ning Tang
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, 410125, People's Republic of China
| | - Huafeng Deng
- Long Ping Branch, College of Biology, Hunan University, Changsha, 410082, People's Republic of China
| | - Mengliang Cao
- Long Ping Branch, College of Biology, Hunan University, Changsha, 410082, People's Republic of China.
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, 410125, People's Republic of China.
- School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University, Sanya, 572025, People's Republic of China.
- National Center of Technology Innovation for Saline-Alkali Tolerant Rice in Sanya, Sanya, 572000, People's Republic of China.
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4
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Wang W, Malka R, Lindemeier M, Cyprys P, Tiedemann S, Sun K, Zhang X, Xiong H, Sprunck S, Sun MX. EGG CELL 1 contributes to egg-cell-dependent preferential fertilization in Arabidopsis. NATURE PLANTS 2024; 10:268-282. [PMID: 38287093 DOI: 10.1038/s41477-023-01616-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 12/20/2023] [Indexed: 01/31/2024]
Abstract
During double fertilization in angiosperms, the pollen tube delivers two sperm cells into an embryo sac; one sperm cell fuses with an egg cell, and the other sperm cell fuses with the central cell. It has long been proposed that the preference for fusion with one or another female gamete cell depends on the sperm cells and occurs during gamete recognition. However, up to now, sperm-dependent preferential fertilization has not been demonstrated, and results on preferred fusion with either female gamete have remained conflicting. To investigate this topic, we generated Arabidopsis thaliana mutants that produce single sperm-like cells or whose egg cells are eliminated; we found that although the three different types of sperm-like cell are functionally equivalent in their ability to fertilize the egg and the central cell, each type of sperm-like cell fuses predominantly with the egg cell. This indicates that it is the egg cell that controls its preferential fertilization. We also found that sperm-activating small secreted EGG CELL 1 proteins are involved in the regulation of egg-cell-dependent preferential fertilization, revealing another important role for this protein family during double fertilization.
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Affiliation(s)
- Wei Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Raphael Malka
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Maria Lindemeier
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Philipp Cyprys
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Sophie Tiedemann
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Kaiting Sun
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xuecheng Zhang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Hanxian Xiong
- School of Life Science and Technology, Wuhan Polytechnic University, Wuhan, China.
| | - Stefanie Sprunck
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany.
| | - Meng-Xiang Sun
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China.
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5
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Washburn M, Alaniz-Fabián J, Scroggs T, Nelms B. Single-cell RNA-seq of maize meiocytes and pollen grains. Nat Protoc 2023; 18:3512-3533. [PMID: 37783945 DOI: 10.1038/s41596-023-00889-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 07/11/2023] [Indexed: 10/04/2023]
Abstract
RNA-sequencing (RNA-seq) provides invaluable knowledge on developmental pathways and the effects of mutant phenotypes. Plant reproductive cells have traditionally been difficult to isolate for genomics because they are rare and often deeply embedded within somatic tissues. Here, we present a protocol to isolate single maize meiocytes and pollen grains for RNA-seq. We discuss how to identify and isolate each sample type under a microscope, prepare RNA-seq libraries and analyze the data. This technique has several advantages over alternative methods, combining the ability to target specific rare cell types while resolving cell-to-cell heterogeneity with single-cell RNA-seq. The technique is compatible with minute amounts of starting material (e.g., a single anther), making it possible to collect dense time courses. Furthermore, developmentally synchronized anthers are saved for microscopy, allowing staging to be performed in parallel with expression analysis. Up to 200 cells can be collected in 4-5 h by someone proficient in tissue dissection, and library preparation can be completed in 2 d by researchers experienced in molecular biology and genomics. This protocol will facilitate research on plant reproduction, providing insights critical to plant breeding, genetics and agriculture.
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Affiliation(s)
| | - Jaime Alaniz-Fabián
- National Laboratory of Genomics for Biodiversity, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-LANGEBIO), Irapuato, Mexico
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6
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Zhai X, Bai J, Xu W, Yang X, Jia Z, Xia W, Wu X, Liang Q, Li B, Jia N. The molecular chaperone mtHSC70-1 interacts with DjA30 to regulate female gametophyte development and fertility in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:1677-1698. [PMID: 37294615 DOI: 10.1111/tpj.16347] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/26/2023] [Indexed: 06/10/2023]
Abstract
Arabidopsis mitochondria-targeted heat shock protein 70 (mtHSC70-1) plays important roles in the establishment of cytochrome c oxidase-dependent respiration and redox homeostasis during the vegetative growth of plants. Here, we report that knocking out the mtHSC70-1 gene led to a decrease in plant fertility; the fertility defect of the mutant was completely rescued by introducing the mtHSC70-1 gene. mtHSC70-1 mutants also showed defects in female gametophyte (FG) development, including delayed mitosis, abnormal nuclear position, and ectopic gene expression in the embryo sacs. In addition, we found that an Arabidopsis mitochondrial J-protein gene (DjA30) mutant, j30+/- , had defects in FG development and fertility similar to those of mtHSC70-1 mutant. mtHSC70-1 and DjA30 had similar expression patterns in FGs and interacted in vivo, suggesting that these two proteins might cooperate during female gametogenesis. Further, respiratory chain complex IV activity in mtHSC70-1 and DjA30 mutant embryo sacs was markedly downregulated; this led to the accumulation of mitochondrial reactive oxygen species (ROS). Scavenging excess ROS by introducing Mn-superoxide dismutase 1 or catalase 1 gene into the mtHSC70-1 mutant rescued FG development and fertility. Altogether, our results suggest that mtHSC70-1 and DjA30 are essential for the maintenance of ROS homeostasis in the embryo sacs and provide direct evidence for the roles of ROS homeostasis in embryo sac maturation and nuclear patterning, which might determine the fate of gametic and accessory cells.
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Affiliation(s)
- Xiaoting Zhai
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
- College of Agriculture and Forestry, Hebei North University, Zhangjiakou, 075000, China
| | - Jiaoteng Bai
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Wenyan Xu
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Xiujuan Yang
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Zichao Jia
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Wenxuan Xia
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Xiaoqing Wu
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Qi Liang
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Bing Li
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Research Center of the Basic Discipline of Cell Biology, Hebei Normal University, Shijiazhuang, 050024, China
- Hebei Collaboration Innovation Center for Cell Signaling and Environmental Adaptation, Hebei Normal University, Shijiazhuang, 050024, China
| | - Ning Jia
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, China
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7
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Yu SX, Hu LQ, Yang LH, Zhang T, Dai RB, Zhang YJ, Xie ZP, Lin WH. RLI2 regulates Arabidopsis female gametophyte and embryo development by facilitating the assembly of the translational machinery. Cell Rep 2023; 42:112741. [PMID: 37421624 DOI: 10.1016/j.celrep.2023.112741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 04/01/2023] [Accepted: 06/20/2023] [Indexed: 07/10/2023] Open
Abstract
Eukaryotic protein translation is a complex process that requires the participation of different proteins. Defects in the translational machinery often result in embryonic lethality or severe growth defects. Here, we report that RNase L inhibitor 2/ATP-BINDING CASSETTE E2 (RLI2/ABCE2) regulates translation in Arabidopsis thaliana. Null mutation of rli2 is gametophytic and embryonic lethal, whereas knockdown of RLI2 causes pleiotropic developmental defects. RLI2 interacts with several translation-related factors. Knockdown of RLI2 affects the translational efficiency of a subset of proteins involved in translation regulation and embryo development, indicating that RLI2 has critical roles in these processes. In particular, RLI2 knockdown mutant exhibits decreased expression of genes involved in auxin signaling and female gametophyte and embryo development. Therefore, our results reveal that RLI2 facilitates assembly of the translational machinery and indirectly modulates auxin signaling to regulate plant growth and development.
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Affiliation(s)
- Shi-Xia Yu
- The Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Collaborative Innovation Center of Agri-Seeds/Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Li-Qin Hu
- The Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Collaborative Innovation Center of Agri-Seeds/Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Lu-Han Yang
- The Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Tao Zhang
- The Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ruo-Bing Dai
- Zhiyuan College, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yan-Jie Zhang
- The Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhi-Ping Xie
- The Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Wen-Hui Lin
- The Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Collaborative Innovation Center of Agri-Seeds/Joint Center for Single Cell Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
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8
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Wang X, Liu X, Yi X, Wang M, Shi W, Li R, Tang W, Zhang L, Sun M, Peng X. The female germ unit is essential for pollen tube funicular guidance in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2023; 238:155-168. [PMID: 36527238 DOI: 10.1111/nph.18686] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
In angiosperm, two immotile sperm cells are delivered to the female gametes for fertilization by a pollen tube, which perceives guidance cues from ovules at least at two critical sites, micropyle for short-distance guidance and funiculus for comparably longer distance guidance. Compared with the great progress in understanding pollen tube micropylar guidance, little is known about the signaling for funicular guidance. Here, we show that funiculus plays an important role in pollen tube guidance and report that female gametophyte (FG) plays a critical role in funicular guidance by analysis of a 3-dehydroquinate synthase (DHQS) mutant. Loss function of DHQS in FG interrupts pollen tube funicular guidance, suggesting that the guiding signal is generated from FG. We show the evidence that the capacity of funicular guidance is established during FG functional specification after the establishment of cell identity. Specific expression of DHQS in the synergid cells, central cells, or egg cells can rescue funicular guidance defect in dhqs/+, indicating all the female germ unit cells are involved in the funicular guidance. The finding reveals that the attracting signal of pollen tube funicular guidance was generated at a site and stage manner and provides novel clue to locate and search for the signal.
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Affiliation(s)
- Xiu Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Xiangfeng Liu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xinlei Yi
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Min Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Wenxin Shi
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Ruiping Li
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Wenyue Tang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Liyao Zhang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Mengxiang Sun
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xiongbo Peng
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
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9
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Li M, Lv M, Wang X, Cai Z, Yao H, Zhang D, Li H, Zhu M, Du W, Wang R, Wang Z, Kui H, Hou S, Li J, Yi J, Gou X. The EPFL-ERf-SERK signaling controls integument development in Arabidopsis. THE NEW PHYTOLOGIST 2023; 238:186-201. [PMID: 36564978 DOI: 10.1111/nph.18701] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
As the seed precursor, the ovule produces the female gametophyte (or embryo sac), and the subsequent double fertilization occurs in it. The integuments emerge sequentially from the integument primordia at the early stages of ovule development and finally enwrap the embryo sac gradually during gametogenesis, protecting and nursing the embryo sac. However, the mechanisms regulating integument development are still obscure. In this study, we show that SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASES (SERKs) play essential roles during integument development in Arabidopsis thaliana. The serk1/2/3 triple mutant shows arrested integuments and abnormal embryo sacs, similar defects also found in the triple loss-of-function mutants of ERECTA family (ERf) genes. Ovules of serk1/2/3 er erl1/2 show defects similar to er erl1/2 and serk1/2/3. Results of yeast two-hybrid analyses, bimolecular fluorescence complementation (BiFC) analyses, and co-immunoprecipitation assays demonstrated that SERKs interact with ERf, which depends on EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family small peptides. The sextuple mutant epfl1/2/3/4/5/6 shows integument defects similar to both of er erl1/2 and serk1/2/3. Our results demonstrate that ERf-SERK-mediated EPFL signaling orchestrates the development of the female gametophyte and the surrounding sporophytic integuments.
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Affiliation(s)
- Meizhen Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Minghui Lv
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
- School of Life Sciences, Guangzhou University, Guangzhou, Guangdong, 510006, China
| | - Xiaojuan Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Zeping Cai
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
- College of Forestry, Hainan University, Haikou, Hainan, 570228, China
| | - Hongrui Yao
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Dongyang Zhang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Huiqiang Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
- College of Life Sciences, Henan Agricultural University, Zhengzhou, Henan, 450002, China
| | - Mingsong Zhu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Wenbin Du
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Ruoshi Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Zhe Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Hong Kui
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Suiwen Hou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Jia Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
- School of Life Sciences, Guangzhou University, Guangzhou, Guangdong, 510006, China
| | - Jing Yi
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
| | - Xiaoping Gou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, 730000, China
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10
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Qi X, Gao H, Lv R, Mao W, Zhu J, Liu C, Mao L, Li X, Xie C. CRISPR/dCas-mediated gene activation toolkit development and its application for parthenogenesis induction in maize. PLANT COMMUNICATIONS 2023; 4:100449. [PMID: 36089769 PMCID: PMC10030315 DOI: 10.1016/j.xplc.2022.100449] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/15/2022] [Accepted: 09/09/2022] [Indexed: 05/04/2023]
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems can be engineered as programmable transcription factors to either activate (CRISPRa) or inhibit transcription. Apomixis is extremely valuable for the seed industry in breeding clonal seeds with pure genetic backgrounds. We report here a CRISPR/dCas9-based toolkit equipped with dCas9-VP64 and MS2-p65-HSF1 effectors that may specifically target genes with high activation capability. We explored the application of in vivo CRISPRa targeting of maize BABY BOOM2 (ZmBBM2), acting as a fertilization checkpoint, as a means to engineer parthenogenesis. We detected ZmBBM2 transcripts only in egg cells but not in other maternal gametic cells. Activation of ZmBBM2 in egg cells in vivo caused maternal cell-autonomous parthenogenesis to produce haploid seeds. Our work provides a highly specific gene-activation CRISPRa technology for target cells and verifies its application for parthenogenesis induction in maize.
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Affiliation(s)
- Xiantao Qi
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China; Hainan Yazhou Bay Seed Lab, Hainan Province 572024 China
| | - Huimin Gao
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China
| | - Renyao Lv
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China
| | - Wenbo Mao
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China
| | - Jinjie Zhu
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China; Hainan Yazhou Bay Seed Lab, Hainan Province 572024 China
| | - Changling Liu
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China
| | - Long Mao
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China
| | - Xinhai Li
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China; Hainan Yazhou Bay Seed Lab, Hainan Province 572024 China
| | - Chuanxiao Xie
- Institute of Crop Science, Chinese Academy of Agricultural Sciences, National Key Facility for Crop Gene Resources and Genetic Improvement, Beijing 100081 China; Hainan Yazhou Bay Seed Lab, Hainan Province 572024 China.
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11
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Wang L, Yang K, Wang Q, Xiao W. Genetic analysis of DNA-damage tolerance pathways in Arabidopsis. PLANT CELL REPORTS 2023; 42:153-164. [PMID: 36319861 DOI: 10.1007/s00299-022-02942-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
Genetic analysis revealed a two-branch DNA-damage tolerance mechanism in Arabidopsis, namely translesion DNA synthesis and error-free lesion bypass, represented by Rev3 and Rad5a-Uev1C/D, respectively. DNA-damage tolerance (DDT) is a mechanism by which cells complete replication in the presence of replication-blocking lesions. In budding yeast, DDT is achieved through Rad6-Rad18-mediated monoubiquitination of proliferating cell nuclear antigen (PCNA), which promotes translesion DNA synthesis (TLS) and is followed by Ubc13-Mms2-Rad5 mediated K63-linked PCNA polyubiquitination that promotes error-free lesion bypass. Arabidopsis and other known plant genomes contain all of the above homologous genes except RAD18, and whether plants possess an intact DDT mechanism is unclear. In this study, we created Arabidopsis UEV1 (homologous to yeast MMS2) gene mutations and obtained two sets of double mutant lines Atuev1ab and Atuev1cd. It turned out that the Atuev1cd, but not the Atuev1ab mutant, was sensitive to DNA damage. Genetic analyses revealed that AtUEV1C/D and AtRAD5a function in the same pathway, while TLS represented by AtREV3 functions in a separate pathway in response to replication-blocking lesions. Furthermore, unlike budding yeast RAD5 that also functions in the TLS pathway, AtRAD5a is not required for TLS. Observations in this study collectively establish a two-branch DDT model in plants with similarity to and difference from the yeast DDT.
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Affiliation(s)
- Linxiao Wang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada
| | - Kun Yang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Qiuheng Wang
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Wei Xiao
- Beijing Key Laboratory of DNA Damage Responses and College of Life Sciences, Capital Normal University, Beijing, 100048, China.
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada.
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12
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Abstract
Introducing asexual reproduction through seeds - apomixis - into crop species could revolutionize agriculture by allowing F1 hybrids with enhanced yield and stability to be clonally propagated. Engineering synthetic apomixis has proven feasible in inbred rice through the inactivation of three genes (MiMe), which results in the conversion of meiosis into mitosis in a line ectopically expressing the BABYBOOM1 (BBM1) parthenogenetic trigger in egg cells. However, only 10-30% of the seeds are clonal. Here, we show that synthetic apomixis can be achieved in an F1 hybrid of rice by inducing MiMe mutations and egg cell expression of BBM1 in a single step. We generate hybrid plants that produce more than 95% of clonal seeds across multiple generations. Clonal apomictic plants maintain the phenotype of the F1 hybrid along successive generations. Our results demonstrate that there is no barrier to almost fully penetrant synthetic apomixis in an important crop species, rendering it compatible with use in agriculture.
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13
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Zhu M, Tao L, Zhang J, Liu R, Tian H, Hu C, Zhu Y, Li M, Wei Z, Yi J, Li J, Gou X. The type-B response regulators ARR10, ARR12, and ARR18 specify the central cell in Arabidopsis. THE PLANT CELL 2022; 34:4714-4737. [PMID: 36130292 PMCID: PMC9709988 DOI: 10.1093/plcell/koac285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 09/15/2022] [Indexed: 06/15/2023]
Abstract
In Arabidopsis thaliana, the female gametophyte consists of two synergid cells, an egg cell, a diploid central cell, and three antipodal cells. CYTOKININ INDEPENDENT 1 (CKI1), a histidine kinase constitutively activating the cytokinin signaling pathway, specifies the central cell and restricts the egg cell. However, the mechanism regulating CKI1-dependent central cell specification is largely unknown. Here, we showed that the type-B ARABIDOPSIS RESPONSE REGULATORS10, 12, and 18 (ARR10/12/18) localize at the chalazal pole of the female gametophyte. Phenotypic analysis showed that the arr10 12 18 triple mutant is female sterile. We examined the expression patterns of embryo sac marker genes and found that the embryo sac of arr10 12 18 plants had lost central cell identity, a phenotype similar to that of the Arabidopsis cki1 mutant. Genetic analyses demonstrated that ARR10/12/18, CKI1, and ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN2, 3, and 5 (AHP2/3/5) function in a common pathway to regulate female gametophyte development. In addition, constitutively activated ARR10/12/18 in the cki1 embryo sac partially restored the fertility of cki1. Results of transcriptomic analysis supported the conclusion that ARR10/12/18 and CKI1 function together to regulate the identity of the central cell. Our results demonstrated that ARR10/12/18 function downstream of CKI1-AHP2/3/5 as core factors to determine cell fate of the female gametophyte.
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Affiliation(s)
- Mingsong Zhu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Liang Tao
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jinghua Zhang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Ruini Liu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Hongai Tian
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Chong Hu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yafen Zhu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Meizhen Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Zhuoyun Wei
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jing Yi
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Jia Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Xiaoping Gou
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
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14
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Gupta N, Jain SK, Tomar BS, Anand A, Singh J, Sagar V, Kumar R, Singh V, Chaubey T, Abd-Elsalam KA, Singh AK. Impact of Foliar Application of ZnO and Fe 3O 4 Nanoparticles on Seed Yield and Physio-Biochemical Parameters of Cucumber ( Cucumis sativus L.) Seed under Open Field and Protected Environment vis a vis during Seed Germination. PLANTS (BASEL, SWITZERLAND) 2022; 11:3211. [PMID: 36501251 PMCID: PMC9738616 DOI: 10.3390/plants11233211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/04/2022] [Accepted: 11/07/2022] [Indexed: 06/17/2023]
Abstract
Nutritionally rich cucumber seeds remain in demand in the agricultural, health and cosmetic sectors as they are essential for a successful crop stand establishment and seed-based products. However, the production of cucumber seeds is impeded by source limitation and nutrient deficiency. The foliar application of micronutrients can supplement this deficiency and overcome the physiological setback. An experiment was undertaken to compare the impacts of the foliar application of Fe and Zn, as nanoparticles and fertilizers, on the yield and seed quality of cucumber under open and protected environments. A foliar spray of nano-ZnO (ZnNPs) and nano-Fe3O4 (FeNPs) at 100, 200 and 300 mg L-1, as well as ZnSO4 and FeSO4 as fertilizer (0.5%), was conducted at the vegetative stage and pre- and post-flowering stages. The NPs had a greater efficacy in an open field than in the protected (naturally ventilated poly house) environment. The application of both NPs increased seed yield (51.7-52.2%), total chlorophyll content (15.9-17.3%) and concentration of Zn and Fe in the fruit and the seed, by 2.0-58.5% and 5.0-30.5%, respectively. A significant increase in starch, soluble proteins, soluble sugars and oil content was observed in the seeds from the NP treated plants. NP treatment also enhanced the germination-related parameters, such as percent germination (16.8-17.0%), rate of germination (18.0-22.2%) and seedling vigor (59.8-72.6%). The biochemical characterization showed a significant improvement in the seed water uptake and the activity of hydrolytic enzymes (amylase and protease) in the germinating seed. The involvement of reactive oxygen species (superoxide anion and hydrogen peroxide) and antioxidant enzymes (Superoxide dismutase, Catalase and Peroxidase) in the germination process was indicated by an increase in their activities in the seeds from NP treated plants. Hence, the study proposes the potential benefit of the foliar application of 300 mg L-1 ZnNPs and 200 mg L-1 FeNPs at crucial stages of plant growth to improve the yield and seed quality in cucumbers.
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Affiliation(s)
- Nakul Gupta
- ICAR—Indian Institute of Vegetable Research, PB-01, Po-Jakhini (Sahanshahpur), Varanasi 221305, India
- ICAR—Indian Agricultural Research Institute, New Delhi 110012, India
| | - Sudhir Kumar Jain
- ICAR—Indian Agricultural Research Institute, New Delhi 110012, India
| | | | - Anjali Anand
- ICAR—Indian Agricultural Research Institute, New Delhi 110012, India
| | - Jogendra Singh
- ICAR—Indian Agricultural Research Institute, New Delhi 110012, India
| | - Vidya Sagar
- ICAR—Indian Institute of Vegetable Research, PB-01, Po-Jakhini (Sahanshahpur), Varanasi 221305, India
| | - Rajesh Kumar
- ICAR—Indian Institute of Vegetable Research, PB-01, Po-Jakhini (Sahanshahpur), Varanasi 221305, India
| | - Vikas Singh
- ICAR—Indian Institute of Vegetable Research, PB-01, Po-Jakhini (Sahanshahpur), Varanasi 221305, India
| | - Tribhuvan Chaubey
- ICAR—Indian Institute of Vegetable Research, PB-01, Po-Jakhini (Sahanshahpur), Varanasi 221305, India
| | - Kamel A. Abd-Elsalam
- Plant Pathology Research Institute, Agricultural Research Center, Giza 12619, Egypt
| | - Awani Kumar Singh
- ICAR—Indian Agricultural Research Institute, New Delhi 110012, India
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15
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Xia Y, Wang Y, Hu Y, Zhan Y, Dan J, Tang N, Tian J, Cao M. Double-seedlings and embryo-free seeds generated by genetic engineering. FRONTIERS IN PLANT SCIENCE 2022; 13:999031. [PMID: 36262658 PMCID: PMC9576183 DOI: 10.3389/fpls.2022.999031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Apomixis can fix the heterosis of Hybrid F1, by maintaining its heterozygous genotype, and is an ideal way for the development of hybrid rice. In this paper, we designed an engineering strategy for realizing apomictic reproduction of hybrid rice in the way of induce adventitious embryos. An embryogenesis gene, AtWUS, controlled by the ovule-specific promoter, a ribonuclease gene Barnase driven by the egg cell-specific promoter pDD45, and an inactivation gene ZmAA1 driven by the pollen-specific promoter pG47 were simultaneously integrated into one T-DNA, and co-transformed with the second T-DNA carrying a Barstar gene. Double-seedlings were observed in transgenic line. Whole-genome sequencing and ploidy levels confirmed by flow cytometry showed that one of the double-seedlings was heterozygous diploid and the other seedling was homozygous haploid, which confirmed that embryogenesis in one of the double-seedlings arises from the zygote after fertilization and the other derived from an unfertilized gamete. Meanwhile we obtained embryo-free seeds at frequencies of 2.6% to 3.8% in T1 generation, and 0.75% to 3% in T2 generation. Though we did not obtained adventitious embryos in hybrid rice in this study, the phenomenon of double-seedlings and embryo-free seeds in transgenic line was informative and strongly suggested that endosperm development is an autonomously organized process in rice, independent of egg cell fertilization and embryo-endosperm communication. This provides novel insights into the induction of haploid embryos and lends theoretical support to successful clonal propagation using synthetic apomixis.
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Affiliation(s)
- Yumei Xia
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, China
- National Center of Technology Innovation for Saline-Alkali Tolerant Rice in Sanya, Sanya, China
| | - Yao Wang
- Long Ping Branch, Graduate School of Hunan University, Changsha, China
| | - Yuanyi Hu
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, China
- National Center of Technology Innovation for Saline-Alkali Tolerant Rice in Sanya, Sanya, China
| | - Yijie Zhan
- Long Ping Branch, Graduate School of Hunan University, Changsha, China
| | - Junhao Dan
- Long Ping Branch, Graduate School of Hunan University, Changsha, China
| | - Ning Tang
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, China
| | - Junyou Tian
- Long Ping Branch, Graduate School of Hunan University, Changsha, China
| | - Mengliang Cao
- State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha, China
- National Center of Technology Innovation for Saline-Alkali Tolerant Rice in Sanya, Sanya, China
- Long Ping Branch, Graduate School of Hunan University, Changsha, China
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16
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Doronina TV, Ashapkin VV, Lazareva EM. Wheat Antipodal Cells with Polytene Chromosomes in the Embryo Sac Are Key to Understanding the Formation of Grain in Cereals. BIOLOGY 2022; 11:biology11091340. [PMID: 36138819 PMCID: PMC9495325 DOI: 10.3390/biology11091340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/07/2022] [Accepted: 09/09/2022] [Indexed: 11/27/2022]
Abstract
Simple Summary The present work is devoted to the features of antipodal cells at the early stages of wheat seed development, ensuring the formation and protection of a full-fledged grain. Using the methods of cell and molecular biology, changes in the structure of these cells and their components during active functioning and death are shown. For the first time, data on the expression of some genes confirming the functions of antipodal cells were obtained. The characteristic features of cells at the stages of death were revealed. The data obtained indicate the key role of antipodal cells in the process of grain maturation and subsequently allow us to identify substances that ensure the formation of tissue, which is the food of the whole world. Abstract The ultrastructure of antipodal cells of the Triticum aestivum embryo sac was studied at different stages of differentiation and programmed cell death. The importance of cell function in the antipodal complex is evidenced by the fact that it is fully formed before double fertilization, past the stages of proliferation of three initial cells, and several rounds of genome endoreduplication during differentiation. In this study, we showed that the actively synthesizing organelles, the granular reticulum, and Golgi apparatus, alter their structure during differentiation and death. The polymorphism of the shape of the mitochondria and plastids was demonstrated. For the first time, the actin filaments of the cytoskeleton and numerous multivesicular bodies associated with the plasma membrane were detected in the cytoplasm. The transfer of cytoplasm and organelles between antipodal cells and into the coenocyte of the endosperm was confirmed. DNA breaks and the release of cytochrome c at various stages of death were revealed. To understand the function of the antipodal cells, a quantitative PCR analysis of the expression of wheat genes involved in protective, antistress, and metabolic processes was carried out. We found that gene expression in the antipodal cell fraction was increased compared with that in the whole embryo sac. On the basis of the data, we assume that antipodal cells produce both nutrients and numerous antistress factors that ensure the normal development of the endosperm of the grain, which, in turn, further ensures the development of the embryo.
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Affiliation(s)
- Tatiana V. Doronina
- Biology Faculty, Lomonosov Moscow State University, Moscow 119234, Russia
- Correspondence:
| | - Vasily V. Ashapkin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| | - Elena M. Lazareva
- Biology Faculty, Lomonosov Moscow State University, Moscow 119234, Russia
- All-Russia Research Institute for Agricultural Biotechnology, Moscow 119234, Russia
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17
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Chahal LS, Conner JA, Ozias-Akins P. Phylogenetically Distant BABY BOOM Genes From Setaria italica Induce Parthenogenesis in Rice. FRONTIERS IN PLANT SCIENCE 2022; 13:863908. [PMID: 35909735 PMCID: PMC9329937 DOI: 10.3389/fpls.2022.863908] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 06/13/2022] [Indexed: 06/02/2023]
Abstract
The combination of apomixis and hybrid production is hailed as the holy grail of agriculture for the ability of apomixis to fix heterosis of F1 hybrids in succeeding generations, thereby eliminating the need for repeated crosses to produce F1 hybrids. Apomixis, asexual reproduction through seed, achieves this feat by circumventing two processes that are fundamental to sexual reproduction (meiosis and fertilization) and replacing them with apomeiosis and parthenogenesis, resulting in seeds that are clonal to the maternal parent. Parthenogenesis, embryo development without fertilization, has been genetically engineered in rice, maize, and pearl millet using PsASGR-BABY BOOM-like (PsASGR-BBML) transgenes and in rice using the OsBABY BOOM1 (OsBBM1) cDNA sequence when expressed under the control of egg cell-specific promoters. A phylogenetic analysis revealed that BABY BOOM (BBM)/BBML genes from monocots cluster within three different clades. The BBM/BBML genes shown to induce parthenogenesis cluster within clade 1 (the ASGR-BBML clade) along with orthologs from other monocot species, such as Setaria italica. For this study, we tested the parthenogenetic potential of three BBM transgenes from S. italica, each a member of a different phylogenetic BBM clade. All transgenes were genomic constructs under the control of the AtDD45 egg cell-specific promoter. All SiBBM transgenes induced various levels of parthenogenetic embryo development, resulting in viable haploid T1 seedlings. Poor seed set and lower haploid seed production were characteristics of multiple transgenic lines. The results presented in this study illustrate that further functional characterization of BBMs in zygote/embryo development is warranted.
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Affiliation(s)
- Lovepreet Singh Chahal
- Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Tifton, GA, United States
| | - Joann A. Conner
- Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Tifton, GA, United States
- Department of Horticulture, University of Georgia, Tifton, GA, United States
| | - Peggy Ozias-Akins
- Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Tifton, GA, United States
- Department of Horticulture, University of Georgia, Tifton, GA, United States
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18
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Sidhu GS, Conner JA, Ozias-Akins P. Controlled Induction of Parthenogenesis in Transgenic Rice via Post-translational Activation of PsASGR-BBML. FRONTIERS IN PLANT SCIENCE 2022; 13:925467. [PMID: 35873991 PMCID: PMC9305695 DOI: 10.3389/fpls.2022.925467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
Modern plant breeding programs rely heavily on the generation of homozygous lines, with the traditional process requiring the inbreeding of a heterozygous cross for five to six generations. Doubled haploid (DH) technology, a process of generating haploid plants from an initial heterozygote, followed by chromosome doubling, reduces the process to two generations. Currently established in vitro methods of haploid induction include androgenesis and gynogenesis, while in vivo methods are based on uni-parental genome elimination. Parthenogenesis, embryogenesis from unfertilized egg cells, presents another potential method of haploid induction. PsASGR-BABY BOOM-like, an AP2 transcription factor, induces parthenogenesis in a natural apomictic species, Pennisetum squamulatum (Cenchrus squamulatus) and PsASGR-BBML transgenes promote parthenogenesis in several crop plants, including rice, maize, and pearl millet. The dominant nature of PsASGR-BBML transgenes impedes their use in DH technology. Using a glucocorticoid-based post-translational regulation system and watering with a 100 μM DEX solution before anthesis, PsASGR-BBML can be regulated at the flowering stage to promote parthenogenesis. Conditional expression presents a novel opportunity to use parthenogenetic genes in DH production technology and to elucidate the molecular mechanism underlying parthenogenetic embryogenesis.
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Affiliation(s)
- Gurjot Singh Sidhu
- Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Tifton, GA, United States
| | - Joann A. Conner
- Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Tifton, GA, United States
- Department of Horticulture, University of Georgia, Tifton, GA, United States
| | - Peggy Ozias-Akins
- Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Tifton, GA, United States
- Department of Horticulture, University of Georgia, Tifton, GA, United States
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19
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Toda E, Kiba T, Kato N, Okamoto T. Isolation of gametes and zygotes from Setaria viridis. JOURNAL OF PLANT RESEARCH 2022; 135:627-633. [PMID: 35534650 DOI: 10.1007/s10265-022-01393-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/25/2022] [Indexed: 06/14/2023]
Abstract
Setaria viridis, the wild ancestor of foxtail millet (Setaria italica), is an effective model plant for larger C4 crops because S. viridis has several desirable traits, such as short generation time, prolific seed production and a small genome size. These advantages are well suited for investigating molecular mechanisms in angiosperms, especially C4 crop species. Here, we report a procedure for isolating gametes and zygotes from S. viridis flowers. To isolate egg cells, ovaries were harvested from unpollinated mature flowers and cut transversely, which allowed direct access to the embryo sac. Thereafter, an egg cell was released from the cut end of the basal portion of the dissected ovary. To isolate sperm cells, pollen grains released from anthers were immersed in a mannitol solution, resulting in pollen-grain bursting, which released sperm cells. Additionally, S. viridis zygotes were successfully isolated from freshly pollinated flowers. Isolated zygotes cultured in a liquid medium developed into globular-like embryos and cell masses. Thus, isolated S. viridis gametes, zygotes and embryos are attainable for detailed observations and investigations of fertilization and developmental events in angiosperms.
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Affiliation(s)
- Erika Toda
- Plant Breeding Innovation Laboratory, RIKEN Cluster for Science, Technology and Innovation Hub, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan.
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji, Tokyo, 192-0392, Japan.
- Department of Biological Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
| | - Takatoshi Kiba
- Plant Breeding Innovation Laboratory, RIKEN Cluster for Science, Technology and Innovation Hub, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Norio Kato
- Plant Breeding Innovation Laboratory, RIKEN Cluster for Science, Technology and Innovation Hub, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji, Tokyo, 192-0392, Japan
| | - Takashi Okamoto
- Plant Breeding Innovation Laboratory, RIKEN Cluster for Science, Technology and Innovation Hub, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji, Tokyo, 192-0392, Japan
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20
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Abstract
The zygote is a totipotent structure that develops into an embryo with all of the cells needed to produce an entire plant. The BABY BOOM (BBM) transcription factor induces spontaneous asexual embryo development on plant organs when ectopically expressed. Although BBM is at the top of a transcriptional network that promotes asexual embryo development, little is known about its expression and role during zygotic embryogenesis. Here we show in Arabidopsis that BBM regulates the progression of zygotic embryo development and embryo patterning, and division and cellularization of the filial endosperm. In line with its role as a totipotency factor, ectopic BBM expression in the egg cell is also sufficient to induce haploid embryo development in Arabidopsis and dicot crops. The BABY BOOM (BBM) AINTEGUMENTA-LIKE (AIL) AP2/ERF domain transcription factor is a major regulator of plant cell totipotency, as it induces asexual embryo formation when ectopically expressed. Surprisingly, only limited information is available on the role of BBM during zygotic embryogenesis. Here we reexamined BBM expression and function in the model plant Arabidopsis thaliana (Arabidopsis) using reporter analysis and newly developed CRISPR mutants. BBM was expressed in the embryo from the zygote stage and also in the maternal (nucellus) and filial (endosperm) seed tissues. Analysis of CRISPR mutant alleles for BBM (bbm-cr) and the redundantly acting AIL gene PLETHORA2 (PLT2) (plt2-cr) uncovered individual roles for these genes in the timing of embryo progression. We also identified redundant roles for BBM and PLT2 in endosperm proliferation and cellularization and the maintenance of zygotic embryo development. Finally, we show that ectopic BBM expression in the egg cell of Arabidopsis and the dicot crops Brassica napus and Solanum lycopersicon is sufficient to bypass the fertilization requirement for embryo development. Together these results highlight roles for BBM and PLT2 in seed development and demonstrate the utility of BBM genes for engineering asexual embryo development in dicot species.
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21
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Chen X, Lai S, Zhuang C, Huang J, Hu Y. Sandwich Ct real-time PCR identifies single-copy T-DNA integration accumulating in backbone-free transgenic T 1 Arabidopsis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 318:111204. [PMID: 35351295 DOI: 10.1016/j.plantsci.2022.111204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/27/2022] [Accepted: 01/30/2022] [Indexed: 06/14/2023]
Abstract
A sandwich Ct real-time PCR (SC-PCR) was used to detect single-copy T-DNA plants by visualizing Ct patterns of T-DNA and two reference amplicons. Detecting the T-DNA copy number directly by visualizing the Ct pattern eliminates the errors introduced by multistep calculations of relative Ct values. Using SC-PCR, we found that single-copy T-DNA integrations were more frequent in transgenic T1 Arabidopsis without a vector backbone. On the basis of this phenomenon, we combined the negative screen of the vector backbone and SC-PCR to efficiently identify single-copy T-DNA plants. We found that T-DNA copy number detection was underestimated in transgenic plants containing inverted T-DNA repeats due to hairpin structures formed during PCR, indicating that PCR-based methods for detecting T-DNA copy number should be reevaluated. We solved this problem by releasing T-DNA from the complex structures using restriction enzymes before performing SC-PCR. We also demonstrated that latent Agrobacterium contamination in the T1 transgenic Arabidopsis generated by the floral dip method was exceedingly low and may not affect the detection of T-DNA copy number. Overall, our method provides a whole-set procedure for detecting single-copy T-DNA plants more efficiently than other screening methods including Southern blotting.
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Affiliation(s)
- Xiaojing Chen
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Shaojuan Lai
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Chuxiong Zhuang
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Jilei Huang
- Instrumental Analysis and Research Center, South China Agricultural University, Guangzhou 510642, China
| | - Yufei Hu
- College of Life Sciences, South China Agricultural University, Guangzhou 510642, China.
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22
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Tek MI, Budak K. A New Approach to Develop Resistant Cultivars Against the Plant Pathogens: CRISPR Drives. FRONTIERS IN PLANT SCIENCE 2022; 13:889497. [PMID: 35574145 PMCID: PMC9096106 DOI: 10.3389/fpls.2022.889497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 03/25/2022] [Indexed: 06/01/2023]
Abstract
CRISPR drive is a recent and robust tool that allows durable genetic manipulation of the pest population like human disease vectors such as malaria vector mosquitos. In recent years, it has been suggested that CRISPR drives can also be used to control plant diseases, pests, and weeds. However, using a CRISPR drive in Arabidopsis for the first time in 2021 has been shown to use this technology in plant breeding to obtain homozygous parental lines. This perspective has proposed using CRISPR drive to develop pathogen-resistant cultivars by disrupting the susceptibility gene (S). In the breeding program, CRISPR is used to create S-gene mutations in two parental lines of hybrid cultivars. However, CRISPR must be reapplied or long-term backcrossed for the parental line to obtain homozygous S-mutant cultivars. When a parental line crosses with different parental lines to develop new hybrids, heterozygous S-mutations could not resist in hybrid against the pathogen. CRISPR drives are theoretically valid to develop homozygous S-mutant plants against pathogens by only routine pollination after CRISPR drive transformation to just one parental line. This way, breeders could use this parental line in different crossing combinations without reapplying the genome-editing technique or backcrossing. Moreover, CRISPR drive also could allow the development of marker-free resistant cultivars with modifications on the drive cassette.
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Affiliation(s)
- Mumin Ibrahim Tek
- Molecular Mycology Laboratory, Plant Protection Department, Akdeniz University, Antalya, Turkey
| | - Kubra Budak
- Plant Transformation Laboratory, Plant Biotechnology, Akdeniz University, Antalya, Turkey
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23
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ROS homeostasis mediated by MPK4 and SUMM2 determines synergid cell death. Nat Commun 2022; 13:1746. [PMID: 35365652 PMCID: PMC8976062 DOI: 10.1038/s41467-022-29373-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 03/02/2022] [Indexed: 11/22/2022] Open
Abstract
Sexual plant reproduction depends on the attraction of sperm-cell delivering pollen tubes (PT) by two synergids, followed by their programmed cell death (PCD) in Arabidopsis. Disruption of the mitogen-activated protein kinase 4 (MPK4) by pathogenic effectors activates the resistance protein (R) SUMM2-mediated immunity and cell death. Here we show that synergid preservation and reactive oxygen species (ROS) homeostasis are intimately linked and maintained by MPK4. In mpk4, ROS levels are increased and synergids prematurely undergo PCD before PT-reception. However, ROS scavengers and the disruption of SUMM2, in mpk4, restore ROS homeostasis, synergid maintenance and PT perception, demonstrating that the guardian of MPK4, SUMM2, triggers synergid-PCD. In mpk4/summ2, PTs show a feronia-like overgrowth phenotype. Our results show that immunity-associated PCD and synergid cell death during plant reproduction are regulated by MPK4 underscoring an underlying molecular mechanism for the suppression of plant reproduction during systemic R-mediated immunity. Synergid cells undergo programmed cell death following pollen tube reception and successful fertilization. Here the authors show that premature synergid cell death is prevented by the mitogen activated protein kinase MPK4 and the R protein SUMM2 which maintain ROS homeostasis in Arabidopsis.
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24
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Yin PP, Tang LP, Zhang XS, Su YH. Options for Engineering Apomixis in Plants. FRONTIERS IN PLANT SCIENCE 2022; 13:864987. [PMID: 35371148 PMCID: PMC8967160 DOI: 10.3389/fpls.2022.864987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
In plants, embryogenesis and reproduction are not strictly dependent on fertilization. Several species can produce embryos in seeds asexually, a process known as apomixis. Apomixis is defined as clonal asexual reproduction through seeds, whereby the progeny is identical to the maternal genotype, and provides valuable opportunities for developing superior cultivars, as its induction in agricultural crops can facilitate the development and maintenance of elite hybrid genotypes. In this review, we summarize the current understanding of apomixis and highlight the successful introduction of apomixis methods into sexual crops. In addition, we discuss several genes whose overexpression can induce somatic embryogenesis as candidate genes to induce parthenogenesis, a unique reproductive method of gametophytic apomixis. We also summarize three schemes to achieve engineered apomixis, which will offer more opportunities for the realization of apomictic reproduction.
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25
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Kulichová K, Pieters J, Kumar V, Honys D, Hafidh S. A Plastid-Bound Ankyrin Repeat Protein Controls Gametophyte and Early Embryo Development in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2022; 13:767339. [PMID: 35350296 PMCID: PMC8958021 DOI: 10.3389/fpls.2022.767339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 01/10/2022] [Indexed: 06/14/2023]
Abstract
Proplastids are essential precursors for multi-fate plastid biogenesis, including chloroplast differentiation, a powerhouse for photosynthesis in plants. Arabidopsis ankyrin repeat protein (AKRP, AT5G66055) is a plastid-localized protein with a putative function in plastid differentiation and morphogenesis. Loss of function of akrp leads to embryo developmental arrest. Whether AKRP is critical pre-fertilization has remained unresolved. Here, using reverse genetics, we report a new allele, akrp-3, that exhibited a reduced frequency of mutant embryos (<13%) compared to previously reported alleles. akrp-3 affected both male and female gametophytes resulting in reduced viability, incompetence in pollen tube attraction, altered gametic cell fate, and embryo arrest that were depleted of chlorophyll. AKRP is widely expressed, and the AKRP-GFP fusion localized to plastids of both gametophytes, in isolated chloroplast and co-localized with a plastid marker in pollen and pollen tubes. Cell-type-specific complementation of akrp-3 hinted at the developmental timing at which AKRP might play an essential role. Our findings provide a plausible insight into the crucial role of AKRP in the differentiation of both gametophytes and coupling embryo development with chlorophyll synthesis.
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Affiliation(s)
- Katarína Kulichová
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czechia
| | - Janto Pieters
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czechia
| | - Vinod Kumar
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czechia
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czechia
- Department of Plant Experimental Biology, Faculty of Science, Charles University, Prague, Czechia
| | - Said Hafidh
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czechia
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26
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Zhang Z, Guo Y, Marasigan KM, Conner JA, Ozias-Akins P. Gene activation via Cre/lox-mediated excision in cowpea (Vigna unguiculata). PLANT CELL REPORTS 2022; 41:119-138. [PMID: 34591155 PMCID: PMC8803690 DOI: 10.1007/s00299-021-02789-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/15/2021] [Indexed: 05/11/2023]
Abstract
Expression of Cre recombinase by AtRps5apro or AtDD45pro enabled Cre/lox-mediated recombination at an early embryonic developmental stage upon crossing, activating transgenes in the hybrid cowpea and tobacco. Genetic engineering ideally results in precise spatiotemporal control of transgene expression. To activate transgenes exclusively in a hybrid upon fertilization, we evaluated a Cre/lox-mediated gene activation system with the Cre recombinase expressed by either AtRps5a or AtDD45 promoters that showed activity in egg cells and young embryos. In crosses between Cre recombinase lines and transgenic lines harboring a lox-excision reporter cassette with ZsGreen driven by the AtUbq3 promoter after Cre/lox-mediated recombination, we observed complete excision of the lox-flanked intervening DNA sequence between the AtUbq3pro and the ZsGreen coding sequence in F1 progeny upon genotyping but no ZsGreen expression in F1 seeds or seedlings. The incapability to observe ZsGreen fluorescence was attributed to the activity of the AtUbq3pro. Strong ZsGreen expression in F1 seeds was observed after recombination when ZsGreen was driven by the AtUbq10 promoter. Using the AtDD45pro to express Cre resulted in more variation in recombination frequencies between transgenic lines and crosses. Regardless of the promoter used to regulate Cre, mosaic F1 progeny were rare, suggesting gene activation at an early embryo-developmental stage. Observation of ZsGreen-expressing tobacco embryos at the globular stage from crosses with the AtRps5aproCre lines pollinated by the AtUbq3prolox line supported the early activation mode.
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Affiliation(s)
- Zhifen Zhang
- Department of Horticulture and Institute of Plant Breeding, Genetics and Genomics, University of Georgia, 2356 Rainwater Rd, Tifton, GA, 31793, USA
| | - Yinping Guo
- Department of Horticulture and Institute of Plant Breeding, Genetics and Genomics, University of Georgia, 2356 Rainwater Rd, Tifton, GA, 31793, USA
| | - Kathleen Monfero Marasigan
- Department of Horticulture and Institute of Plant Breeding, Genetics and Genomics, University of Georgia, 2356 Rainwater Rd, Tifton, GA, 31793, USA
| | - Joann A Conner
- Department of Horticulture and Institute of Plant Breeding, Genetics and Genomics, University of Georgia, 2356 Rainwater Rd, Tifton, GA, 31793, USA
| | - Peggy Ozias-Akins
- Department of Horticulture and Institute of Plant Breeding, Genetics and Genomics, University of Georgia, 2356 Rainwater Rd, Tifton, GA, 31793, USA.
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27
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Wang L, Liu Y, Aslam M, Jakada BH, Qin Y, Cai H. The Glycine-Rich Domain Protein GRDP2 Regulates Ovule Development via the Auxin Pathway in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2021; 12:698487. [PMID: 34777406 PMCID: PMC8585784 DOI: 10.3389/fpls.2021.698487] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 10/11/2021] [Indexed: 05/22/2023]
Abstract
The glycine-rich domain proteins (GRDP) have been functionally implicated in the cell wall structure, biotic, and abiotic stress responses. However, little is known about GRDP genes in female gametophyte development of Arabidopsis. This study shows that GRDP2, a GRDP, plays a crucial role in female gametophyte development. In GRDP2 overexpression lines, grdp2-3, the embryo sacs were arrested at FG1 and no nucleus stages. Furthermore, callose staining shows that cell plate formation during megasporogenesis is disturbed in grdp2-3. In contrast, the pollen development is not affected in grdp2-3. The expression patterns of auxin-specific marker lines in female gametophytes showed that the auxin distribution and transport were significantly changed during megagametogenesis in grdp2-3. In addition, compared with the membrane-localized pattern of PIN1, PIN2, and PIN7 in WT, the signals were detected in the cytoplasm in grdp2-3. Together, our data suggest that GRDP2 plays an essential role in auxin-mediated female gametophyte development.
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Affiliation(s)
- Lulu Wang
- Guangxi Key Laboratory of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning, China
| | - Yanhui Liu
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Mohammad Aslam
- Guangxi Key Laboratory of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning, China
| | - Bello Hassan Jakada
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yuan Qin
- Guangxi Key Laboratory of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning, China
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Hanyang Cai
- Guangxi Key Laboratory of Sugarcane Biology, State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, College of Agriculture, Guangxi University, Nanning, China
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
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28
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Julca I, Ferrari C, Flores-Tornero M, Proost S, Lindner AC, Hackenberg D, Steinbachová L, Michaelidis C, Gomes Pereira S, Misra CS, Kawashima T, Borg M, Berger F, Goldberg J, Johnson M, Honys D, Twell D, Sprunck S, Dresselhaus T, Becker JD, Mutwil M. Comparative transcriptomic analysis reveals conserved programmes underpinning organogenesis and reproduction in land plants. NATURE PLANTS 2021; 7:1143-1159. [PMID: 34253868 DOI: 10.1101/2020.10.29.361501] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 06/02/2021] [Indexed: 05/19/2023]
Abstract
The appearance of plant organs mediated the explosive radiation of land plants, which shaped the biosphere and allowed the establishment of terrestrial animal life. The evolution of organs and immobile gametes required the coordinated acquisition of novel gene functions, the co-option of existing genes and the development of novel regulatory programmes. However, no large-scale analyses of genomic and transcriptomic data have been performed for land plants. To remedy this, we generated gene expression atlases for various organs and gametes of ten plant species comprising bryophytes, vascular plants, gymnosperms and flowering plants. A comparative analysis of the atlases identified hundreds of organ- and gamete-specific orthogroups and revealed that most of the specific transcriptomes are significantly conserved. Interestingly, our results suggest that co-option of existing genes is the main mechanism for evolving new organs. In contrast to female gametes, male gametes showed a high number and conservation of specific genes, which indicates that male reproduction is highly specialized. The expression atlas capturing pollen development revealed numerous transcription factors and kinases essential for pollen biogenesis and function.
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Affiliation(s)
- Irene Julca
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Camilla Ferrari
- Max Planck Institute for Molecular Plant Physiology, Potsdam-Golm, Germany
| | - María Flores-Tornero
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Sebastian Proost
- Max Planck Institute for Molecular Plant Physiology, Potsdam-Golm, Germany
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium
- VIB, Center for Microbiology, Leuven, Belgium
| | | | - Dieter Hackenberg
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
- School of Life Sciences, Gibbet Hill Campus, The University of Warwick, Coventry, UK
| | - Lenka Steinbachová
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | - Christos Michaelidis
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | | | - Chandra Shekhar Misra
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Tomokazu Kawashima
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna, BioCenter (VBC), Vienna, Austria
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, USA
| | - Michael Borg
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna, BioCenter (VBC), Vienna, Austria
| | - Frédéric Berger
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna, BioCenter (VBC), Vienna, Austria
| | - Jacob Goldberg
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Mark Johnson
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | - David Twell
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Stefanie Sprunck
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Jörg D Becker
- Instituto Gulbenkian de Ciência, Oeiras, Portugal.
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal.
| | - Marek Mutwil
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
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29
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Julca I, Ferrari C, Flores-Tornero M, Proost S, Lindner AC, Hackenberg D, Steinbachová L, Michaelidis C, Gomes Pereira S, Misra CS, Kawashima T, Borg M, Berger F, Goldberg J, Johnson M, Honys D, Twell D, Sprunck S, Dresselhaus T, Becker JD, Mutwil M. Comparative transcriptomic analysis reveals conserved programmes underpinning organogenesis and reproduction in land plants. NATURE PLANTS 2021; 7:1143-1159. [PMID: 34253868 DOI: 10.1038/s41477-021-00958-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 06/02/2021] [Indexed: 05/22/2023]
Abstract
The appearance of plant organs mediated the explosive radiation of land plants, which shaped the biosphere and allowed the establishment of terrestrial animal life. The evolution of organs and immobile gametes required the coordinated acquisition of novel gene functions, the co-option of existing genes and the development of novel regulatory programmes. However, no large-scale analyses of genomic and transcriptomic data have been performed for land plants. To remedy this, we generated gene expression atlases for various organs and gametes of ten plant species comprising bryophytes, vascular plants, gymnosperms and flowering plants. A comparative analysis of the atlases identified hundreds of organ- and gamete-specific orthogroups and revealed that most of the specific transcriptomes are significantly conserved. Interestingly, our results suggest that co-option of existing genes is the main mechanism for evolving new organs. In contrast to female gametes, male gametes showed a high number and conservation of specific genes, which indicates that male reproduction is highly specialized. The expression atlas capturing pollen development revealed numerous transcription factors and kinases essential for pollen biogenesis and function.
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Affiliation(s)
- Irene Julca
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Camilla Ferrari
- Max Planck Institute for Molecular Plant Physiology, Potsdam-Golm, Germany
| | - María Flores-Tornero
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Sebastian Proost
- Max Planck Institute for Molecular Plant Physiology, Potsdam-Golm, Germany
- Laboratory of Molecular Bacteriology, Department of Microbiology and Immunology, Rega Institute, KU Leuven, Leuven, Belgium
- VIB, Center for Microbiology, Leuven, Belgium
| | | | - Dieter Hackenberg
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
- School of Life Sciences, Gibbet Hill Campus, The University of Warwick, Coventry, UK
| | - Lenka Steinbachová
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | - Christos Michaelidis
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | | | - Chandra Shekhar Misra
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Tomokazu Kawashima
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna, BioCenter (VBC), Vienna, Austria
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, USA
| | - Michael Borg
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna, BioCenter (VBC), Vienna, Austria
| | - Frédéric Berger
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna, BioCenter (VBC), Vienna, Austria
| | - Jacob Goldberg
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Mark Johnson
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czech Republic
| | - David Twell
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Stefanie Sprunck
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Jörg D Becker
- Instituto Gulbenkian de Ciência, Oeiras, Portugal.
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal.
| | - Marek Mutwil
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
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30
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Takeuchi H. The role of diverse LURE-type cysteine-rich peptides as signaling molecules in plant reproduction. Peptides 2021; 142:170572. [PMID: 34004266 DOI: 10.1016/j.peptides.2021.170572] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/12/2021] [Accepted: 05/06/2021] [Indexed: 02/08/2023]
Abstract
In angiosperm sexual reproduction, the male pollen tube undergoes a series of interactions with female tissues. For efficient growth and precise guidance, the pollen tube perceives extracellular ligands. In recent decades, various types of secreted cysteine-rich peptides (CRPs) have been identified as peptide ligands that regulate diverse angiosperm reproduction processes, including pollen tube germination, growth, guidance, and rupture. Notably, in two distant core eudicot plants, multiple LURE-type CRPs were found to be secreted from egg-accompanying synergid cells, and these CRPs act as a cocktail of pollen tube attractants for the final step of pollen tube guidance. LURE-type CRPs have species-preferential activity, even among close relatives, and exhibit remarkably divergent molecular evolution with conserved cysteine frameworks, demonstrating that they play a key role in species recognition in pollen tube guidance. In this review, I focus on "reproductive CRPs," particularly LURE-type CRPs, which underlie common but species-specific mechanisms in angiosperm sexual reproduction, and discuss their action, functional regulation, receptors, and evolution.
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Affiliation(s)
- Hidenori Takeuchi
- Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan; Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.
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31
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Selective inheritance of target genes from only one parent of sexually reproduced F1 progeny in Arabidopsis. Nat Commun 2021; 12:3854. [PMID: 34158505 PMCID: PMC8219824 DOI: 10.1038/s41467-021-24195-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 06/01/2021] [Indexed: 11/08/2022] Open
Abstract
Sexual reproduction constrains progeny to inherit allelic genes from both parents. Selective acquisition of target genes from only one parent in the F1 generation of plants has many potential applications including the elimination of undesired alleles and acceleration of trait stacking. CRISPR/Cas9-based gene drives can generate biased transmission of a preferred allele and convert heterozygotes to homozygotes in insects and mice, but similar strategies have not been implementable in plants because of a lack of efficient homology-directed repair (HDR). Here, we place a gene drive, which consists of cassettes that produce Cas9, guide RNAs (gRNA), and fluorescent markers, into the CRYPTOCHROME 1 (CRY1) gene through CRISPR/Cas9-mediated HDR, resulting in cry1drive lines. After crossing the cry1drive/cry1drive lines to wild type, we observe F1 plants which have DNA at the CRY1 locus from only the cry1drive/cry1drive parent. Moreover, a non-autonomous trans-acting gene drive, in which the gene drive unit and the target gene are located on different chromosomes, converts a heterozygous mutation in the target gene to homozygous. Our results demonstrate that homozygous F1 plants can be obtained through zygotic conversion using a CRISPR/Cas9-based gene drive. Unlike insects and mice, CRISPR/Cas9-based gene drives have not been achieved in plants. Here, the authors demonstrate homozygous F1 Arabidopsis plants can be obtained through zygotic conversion using CRISPR/Cas9-mediated homology-directed repair.
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Xiong H, Wang W, Sun MX. Endosperm development is an autonomously programmed process independent of embryogenesis. THE PLANT CELL 2021; 33:1151-1160. [PMID: 33793916 DOI: 10.1093/plcell/koab007] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
The seeds of flowering plants contain three genetically distinct structures: the embryo, endosperm, and seed coat. The embryo and endosperm need to interact and exchange signals to ensure coordinated growth. Accumulating evidence has confirmed that embryo growth is supported by the nourishing endosperm and regulated by signals originating from the endosperm. Available data also support that endosperm development requires communication with the embryo. Here, using single-fertilization mutants, Arabidopsis thaliana dmp8 dmp9 and gex2, we demonstrate that in the absence of a zygote and embryo, endosperm initiation, syncytium formation, free nuclear cellularization, and endosperm degeneration occur as in the wild type in terms of the cytological process and time course. Although rapid embryo expansion accelerates endosperm breakdown, our findings strongly suggest that endosperm development is an autonomously organized process, independent of egg cell fertilization and embryo-endosperm communication. This work confirms both the altruistic and self-directed nature of the endosperm during coordinated embryo-endosperm development. Our findings provide insights into the intricate interaction between the two fertilization products and will help to distinguish the physiological roles of the signaling between endosperm and embryo. These findings also open new avenues in agro-biotechnology for crop improvement.
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Affiliation(s)
- Hanxian Xiong
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Wei Wang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Meng-Xiang Sun
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
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Yang C, Ge J, Fu X, Luo K, Xu C. Dual Reproductive Cell-Specific Promoter-Mediated Split-Cre/LoxP System Suitable for Exogenous Gene Deletion in Hybrid Progeny of Transgenic Arabidopsis. Int J Mol Sci 2021; 22:5080. [PMID: 34064885 PMCID: PMC8151399 DOI: 10.3390/ijms22105080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/07/2021] [Accepted: 05/10/2021] [Indexed: 01/02/2023] Open
Abstract
Genetically modified (GM) crops possess some superior characteristics, such as high yield and insect resistance, but their biosafety has aroused broad public concern. Some genetic engineering technologies have recently been proposed to remove exogenous genes from GM crops. Few approaches have been applied to maintain advantageous traits, but excising exogenous genes in seeds or fruits from these hybrid crops has led to the generation of harvested food without exogenous genes. In a previous study, split-Cre mediated by split intein could recombine its structure and restore recombination activity in hybrid plants. In the current study, the recombination efficiency of split-Cre under the control of ovule-specific or pollen-specific promoters was validated by hybridization of transgenic Arabidopsis containing the improved expression vectors. In these vectors, all exogenous genes were flanked by two loxP sites, including promoters, resistance genes, reporter genes, and split-Cre genes linked to the reporter genes via LP4/2A. A gene deletion system was designed in which NCre was driven by proDD45, and CCre was driven by proACA9 and proDLL. Transgenic lines containing NCre were used as paternal lines to hybridize with transgenic lines containing CCre. Because this hybridization method results in no co-expression of the NCre and CCre genes controlled by reproduction-specific promoters in the F1 progeny, the desirable characteristics could be retained. After self-crossing in F1 progeny, the expression level and protein activity of reporter genes were detected, and confirmed that recombination of split-Cre had occurred and the exogenous genes were partially deleted. The gene deletion efficiency represented by the quantitative measurements of GUS enzyme activity was over 59%, with the highest efficiency of 73% among variable hybrid combinations. Thus, in the present study a novel dual reproductive cell-specific promoter-mediated gene deletion system was developed that has the potential to take advantage of the merits of GM crops while alleviating biosafety concerns.
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Affiliation(s)
| | | | | | - Keming Luo
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-Environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China; (C.Y.); (J.G.); (X.F.)
| | - Changzheng Xu
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Key Laboratory of Eco-Environments of Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China; (C.Y.); (J.G.); (X.F.)
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Sanjaya A, Kazama Y, Ishii K, Muramatsu R, Kanamaru K, Ohbu S, Abe T, Fujiwara MT. An Argon-Ion-Induced Pale Green Mutant of Arabidopsis Exhibiting Rapid Disassembly of Mesophyll Chloroplast Grana. PLANTS (BASEL, SWITZERLAND) 2021; 10:848. [PMID: 33922223 PMCID: PMC8145761 DOI: 10.3390/plants10050848] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/18/2021] [Accepted: 04/21/2021] [Indexed: 01/13/2023]
Abstract
Argon-ion beam is an effective mutagen capable of inducing a variety of mutation types. In this study, an argon ion-induced pale green mutant of Arabidopsis thaliana was isolated and characterized. The mutant, designated Ar50-33-pg1, exhibited moderate defects of growth and greening and exhibited rapid chlorosis in photosynthetic tissues. Fluorescence microscopy confirmed that mesophyll chloroplasts underwent substantial shrinkage during the chlorotic process. Genetic and whole-genome resequencing analyses revealed that Ar50-33-pg1 contained a large 940 kb deletion in chromosome V that encompassed more than 100 annotated genes, including 41 protein-coding genes such as TYRAAt1/TyrA1, EGY1, and MBD12. One of the deleted genes, EGY1, for a thylakoid membrane-localized metalloprotease, was the major contributory gene responsible for the pale mutant phenotype. Both an egy1 mutant and F1 progeny of an Ar50-33-pg1 × egy1 cross-exhibited chlorotic phenotypes similar to those of Ar50-33-pg1. Furthermore, ultrastructural analysis of mesophyll cells revealed that Ar50-33-pg1 and egy1 initially developed wild type-like chloroplasts, but these were rapidly disassembled, resulting in thylakoid disorganization and fragmentation, as well as plastoglobule accumulation, as terminal phenotypes. Together, these data support the utility of heavy-ion mutagenesis for plant genetic analysis and highlight the importance of EGY1 in the structural maintenance of grana in mesophyll chloroplasts.
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Affiliation(s)
- Alvin Sanjaya
- Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan; (A.S.); (R.M.)
| | - Yusuke Kazama
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
- Faculty of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuoka-Kenjojima, Eiheiji, Yoshida, Fukui 910-1195, Japan
| | - Kotaro Ishii
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
| | - Ryohsuke Muramatsu
- Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan; (A.S.); (R.M.)
| | - Kengo Kanamaru
- Faculty of Agriculture, Kobe University, Nada, Kobe, Hyogo 657-8501, Japan;
| | - Sumie Ohbu
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
| | - Tomoko Abe
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
| | - Makoto T. Fujiwara
- Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda, Tokyo 102-8554, Japan; (A.S.); (R.M.)
- RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (K.I.); (S.O.); (T.A.)
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Zeng W, Huang H, Lin X, Zhu C, Kosami K, Huang C, Zhang H, Duan C, Zhu J, Miki D. Roles of DEMETER in regulating DNA methylation in vegetative tissues and pathogen resistance. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:691-706. [PMID: 33236824 PMCID: PMC8251943 DOI: 10.1111/jipb.13037] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Accepted: 11/03/2020] [Indexed: 05/06/2023]
Abstract
DNA methylation is an epigenetic mark important for genome stability and gene expression. In Arabidopsis thaliana, the 5-methylcytosine DNA glycosylase/demethylase DEMETER (DME) controls active DNA demethylation during the reproductive stage; however, the lethality of loss-of-function dme mutations has made it difficult to assess DME function in vegetative tissues. Here, we edited DME using clustered regularly interspaced short palindromic repeats (CRISPR) /CRISPR-associated protein 9 and created three weak dme mutants that produced a few viable seeds. We also performed central cell-specific complementation in a strong dme mutant and combined this line with mutations in the other three Arabidopsis demethylase genes to generate the dme ros1 dml2 dml3 (drdd) quadruple mutant. A DNA methylome analysis showed that DME is required for DNA demethylation at hundreds of genomic regions in vegetative tissues. A transcriptome analysis of the drdd mutant revealed that DME and the other three demethylases are important for plant responses to biotic and abiotic stresses in vegetative tissues. Despite the limited role of DME in regulating DNA methylation in vegetative tissues, the dme mutants showed increased susceptibility to bacterial and fungal pathogens. Our study highlights the important functions of DME in vegetative tissues and provides valuable genetic tools for future investigations of DNA demethylation in plants.
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Affiliation(s)
- Wenjie Zeng
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
- University of the Chinese Academy of SciencesShanghai201602China
| | - Huan Huang
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
| | - Xueqiang Lin
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
- University of the Chinese Academy of SciencesShanghai201602China
| | - Chen Zhu
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
| | - Ken‐ichi Kosami
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
- Fruit Tree Research Center, Ehime Research Institute of Agriculture, Forestry and FisheriesEhime7910112Japan
| | - Chaofeng Huang
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
| | - Huiming Zhang
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
| | - Cheng‐Guo Duan
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
| | - Jian‐Kang Zhu
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
- Department of Horticulture and Landscape ArchitecturePurdue UniversityWest LafayetteIndiana47907USA
| | - Daisuke Miki
- Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciencesthe Chinese Academy of SciencesShanghai210602China
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Yu X, Zhang X, Zhao P, Peng X, Chen H, Bleckmann A, Bazhenova A, Shi C, Dresselhaus T, Sun MX. Fertilized egg cells secrete endopeptidases to avoid polytubey. Nature 2021; 592:433-437. [PMID: 33790463 DOI: 10.1038/s41586-021-03387-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 02/24/2021] [Indexed: 11/09/2022]
Abstract
Upon gamete fusion, animal egg cells secrete proteases from cortical granules to establish a fertilization envelope as a block to polyspermy1-4. Fertilization in flowering plants is more complex and involves the delivery of two non-motile sperm cells by pollen tubes5,6. Simultaneous penetration of ovules by multiple pollen tubes (polytubey) is usually avoided, thus indirectly preventing polyspermy7,8. How plant egg cells regulate the rejection of extra tubes after successful fertilization is not known. Here we report that the aspartic endopeptidases ECS1 and ECS2 are secreted to the extracellular space from a cortical network located at the apical domain of the Arabidopsis egg cell. This reaction is triggered only after successful fertilization. ECS1 and ECS2 are exclusively expressed in the egg cell and transcripts are degraded immediately after gamete fusion. ECS1 and ESC2 specifically cleave the pollen tube attractor LURE1. As a consequence, polytubey is frequent in ecs1 ecs2 double mutants. Ectopic secretion of these endopeptidases from synergid cells led to a decrease in the levels of LURE1 and reduced the rate of pollen tube attraction. Together, these findings demonstrate that plant egg cells sense successful fertilization and elucidate a mechanism as to how a relatively fast post-fertilization block to polytubey is established by fertilization-induced degradation of attraction factors.
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Affiliation(s)
- Xiaobo Yu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xuecheng Zhang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Peng Zhao
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiongbo Peng
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Hong Chen
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Andrea Bleckmann
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Anastasiia Bazhenova
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany
| | - Ce Shi
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, University of Regensburg, Regensburg, Germany.
| | - Meng-Xiang Sun
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China.
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Susaki D, Suzuki T, Maruyama D, Ueda M, Higashiyama T, Kurihara D. Dynamics of the cell fate specifications during female gametophyte development in Arabidopsis. PLoS Biol 2021; 19:e3001123. [PMID: 33770073 PMCID: PMC7997040 DOI: 10.1371/journal.pbio.3001123] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 01/29/2021] [Indexed: 01/10/2023] Open
Abstract
The female gametophytes of angiosperms contain cells with distinct functions, such as those that enable reproduction via pollen tube attraction and fertilization. Although the female gametophyte undergoes unique developmental processes, such as several rounds of nuclear division without cell plate formation and final cellularization, it remains unknown when and how the cell fate is determined during development. Here, we visualized the living dynamics of female gametophyte development and performed transcriptome analysis of individual cell types to assess the cell fate specifications in Arabidopsis thaliana. We recorded time lapses of the nuclear dynamics and cell plate formation from the 1-nucleate stage to the 7-cell stage after cellularization using an in vitro ovule culture system. The movies showed that the nuclear division occurred along the micropylar–chalazal (distal–proximal) axis. During cellularization, the polar nuclei migrated while associating with the forming edge of the cell plate, and then, migrated toward each other to fuse linearly. We also tracked the gene expression dynamics and identified that the expression of MYB98pro::GFP–MYB98, a synergid-specific marker, was initiated just after cellularization in the synergid, egg, and central cells and was then restricted to the synergid cells. This indicated that cell fates are determined immediately after cellularization. Transcriptome analysis of the female gametophyte cells of the wild-type and myb98 mutant revealed that the myb98 synergid cells had egg cell–like gene expression profiles. Although in myb98, egg cell–specific gene expression was properly initiated in the egg cells only after cellularization, but subsequently expressed ectopically in one of the 2 synergid cells. These results, together with the various initiation timings of the egg cell–specific genes, suggest complex regulation of the individual gametophyte cells, such as cellularization-triggered fate initiation, MYB98-dependent fate maintenance, cell morphogenesis, and organelle positioning. Our system of live-cell imaging and cell type–specific gene expression analysis provides insights into the dynamics and mechanisms of cell fate specifications in the development of female gametophytes in plants. The female gametophytes of angiosperms contain cells with distinct functions, such as those that enable reproduction via pollen tube attraction and fertilization. Live-cell imaging and transcriptome analysis of single female gametophyte cell reveal novel insights into the dynamics and mechanisms of cell fate specifications in the model plant Arabidopsis.
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Affiliation(s)
- Daichi Susaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Takamasa Suzuki
- Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, Kasugai, Japan
| | - Daisuke Maruyama
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Minako Ueda
- Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Nagoya, Japan
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Tetsuya Higashiyama
- Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Nagoya, Japan
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
- * E-mail: (TH); (DK)
| | - Daisuke Kurihara
- Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Nagoya, Japan
- JST, PRESTO, Nagoya, Japan
- * E-mail: (TH); (DK)
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38
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Susaki D, Suzuki T, Maruyama D, Ueda M, Higashiyama T, Kurihara D. Dynamics of the cell fate specifications during female gametophyte development in Arabidopsis. PLoS Biol 2021; 19:e3001123. [PMID: 33770073 DOI: 10.1101/2020.04.07.023028] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 01/29/2021] [Indexed: 05/22/2023] Open
Abstract
The female gametophytes of angiosperms contain cells with distinct functions, such as those that enable reproduction via pollen tube attraction and fertilization. Although the female gametophyte undergoes unique developmental processes, such as several rounds of nuclear division without cell plate formation and final cellularization, it remains unknown when and how the cell fate is determined during development. Here, we visualized the living dynamics of female gametophyte development and performed transcriptome analysis of individual cell types to assess the cell fate specifications in Arabidopsis thaliana. We recorded time lapses of the nuclear dynamics and cell plate formation from the 1-nucleate stage to the 7-cell stage after cellularization using an in vitro ovule culture system. The movies showed that the nuclear division occurred along the micropylar-chalazal (distal-proximal) axis. During cellularization, the polar nuclei migrated while associating with the forming edge of the cell plate, and then, migrated toward each other to fuse linearly. We also tracked the gene expression dynamics and identified that the expression of MYB98pro::GFP-MYB98, a synergid-specific marker, was initiated just after cellularization in the synergid, egg, and central cells and was then restricted to the synergid cells. This indicated that cell fates are determined immediately after cellularization. Transcriptome analysis of the female gametophyte cells of the wild-type and myb98 mutant revealed that the myb98 synergid cells had egg cell-like gene expression profiles. Although in myb98, egg cell-specific gene expression was properly initiated in the egg cells only after cellularization, but subsequently expressed ectopically in one of the 2 synergid cells. These results, together with the various initiation timings of the egg cell-specific genes, suggest complex regulation of the individual gametophyte cells, such as cellularization-triggered fate initiation, MYB98-dependent fate maintenance, cell morphogenesis, and organelle positioning. Our system of live-cell imaging and cell type-specific gene expression analysis provides insights into the dynamics and mechanisms of cell fate specifications in the development of female gametophytes in plants.
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Affiliation(s)
- Daichi Susaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Takamasa Suzuki
- Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University, Kasugai, Japan
| | - Daisuke Maruyama
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Minako Ueda
- Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Nagoya, Japan
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Tetsuya Higashiyama
- Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Nagoya, Japan
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Tokyo, Japan
| | - Daisuke Kurihara
- Institute of Transformative Bio-Molecules (ITbM), Nagoya University, Nagoya, Japan
- JST, PRESTO, Nagoya, Japan
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Cabral LM, Masuda HP, Ballesteros HF, de Almeida-Engler J, Alves-Ferreira M, De Toni KLG, Bizotto FM, Ferreira PCG, Hemerly AS. ABAP1 Plays a Role in the Differentiation of Male and Female Gametes in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2021; 12:642758. [PMID: 33643370 PMCID: PMC7903899 DOI: 10.3389/fpls.2021.642758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 01/22/2021] [Indexed: 05/07/2023]
Abstract
The correct development of a diploid sporophyte body and a haploid gametophyte relies on a strict coordination between cell divisions in space and time. During plant reproduction, these divisions have to be temporally and spatially coordinated with cell differentiation processes, to ensure a successful fertilization. Armadillo BTB Arabidopsis protein 1 (ABAP1) is a plant exclusive protein that has been previously reported to control proliferative cell divisions during leaf growth in Arabidopsis. Here, we show that ABAP1 binds to different transcription factors that regulate male and female gametophyte differentiation, repressing their target genes expression. During male gametogenesis, the ABAP1-TCP16 complex represses CDT1b transcription, and consequently regulates microspore first asymmetric mitosis. In the female gametogenesis, the ABAP1-ADAP complex represses EDA24-like transcription, regulating polar nuclei fusion to form the central cell. Therefore, besides its function during vegetative development, this work shows that ABAP1 is also involved in differentiation processes during plant reproduction, by having a dual role in regulating both the first asymmetric cell division of male gametophyte and the cell differentiation (or cell fusion) of female gametophyte.
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Affiliation(s)
- Luiz M. Cabral
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Departamento de Biologia Celular e Molecular, Instituto de Biologia, Universidade Federal Fluminense, Niterói, Brazil
| | - Hana P. Masuda
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, São Bernardo do Campo, Brazil
| | - Helkin F. Ballesteros
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Janice de Almeida-Engler
- Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Institut Sophia Agrobiotech, Université Côte d’Azur, Sophia Antipolis, France
| | - Márcio Alves-Ferreira
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Karen L. G. De Toni
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fernanda M. Bizotto
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, São Bernardo do Campo, Brazil
| | - Paulo C. G. Ferreira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Adriana S. Hemerly
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- *Correspondence: Adriana S. Hemerly, ;
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Zhan X, Lu Y, Zhu JK, Botella JR. Genome editing for plant research and crop improvement. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:3-33. [PMID: 33369120 DOI: 10.1111/jipb.13063] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 12/22/2020] [Indexed: 05/27/2023]
Abstract
The advent of clustered regularly interspaced short palindromic repeat (CRISPR) has had a profound impact on plant biology, and crop improvement. In this review, we summarize the state-of-the-art development of CRISPR technologies and their applications in plants, from the initial introduction of random small indel (insertion or deletion) mutations at target genomic loci to precision editing such as base editing, prime editing and gene targeting. We describe advances in the use of class 2, types II, V, and VI systems for gene disruption as well as for precise sequence alterations, gene transcription, and epigenome control.
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Affiliation(s)
- Xiangqiang Zhan
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Horticulture, Northwest A&F University, Xianyang, 712100, China
| | - Yuming Lu
- Shanghai Center for Plant Stress Biology, CAS Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology, CAS Center of Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Jose Ramon Botella
- School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland, 4072, Australia
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Li C, Gong X, Zhang B, Liang Z, Wong CE, See BYH, Yu H. TOP1α, UPF1, and TTG2 regulate seed size in a parental dosage-dependent manner. PLoS Biol 2020; 18:e3000930. [PMID: 33156841 PMCID: PMC7673560 DOI: 10.1371/journal.pbio.3000930] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 11/18/2020] [Accepted: 09/24/2020] [Indexed: 11/19/2022] Open
Abstract
Cues of maternal and paternal origins interact to control seed development, and the underlying molecular mechanisms are still far from clear. Here, we show that TOPOISOMERASE Iα (TOP1α), UP-FRAMESHIFT SUPPRESSOR 1 (UPF1), and TRANSPARENT TESTA GLABRA2 (TTG2) gametophytically, biparentally regulate seed size in Arabidopsis. TOP1α and UPF1 are mainly expressed in antipodal cells, and loss of their function leads to ectopic TTG2 expression in these female gametophytic cells. We further demonstrate that TOP1α and UPF1 directly repress TTG2 expression through affecting its chromatin status and determine its relative expression in antipodal cells versus sperm cells, which controls seed size in a dosage-dependent and parent-of-origin-dependent manner. The molecular interplay among these three genes explains their biparental gametophytic effect during diploidy and interploidy reciprocal crosses. Taken together, our findings reveal a molecular framework of parental interaction for seed size control. Cues of maternal and paternal origin interact to control seed development, and the underlying molecular mechanisms are still far from clear. This study shows that in Arabidopsis, the relative dosage of the transcription factor TTG2 between antipodal cells and sperm cells at the beginning of seed development determines seed size under the control of TOP1α and UPF1.
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Affiliation(s)
- Chengxiang Li
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore
| | - Ximing Gong
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
| | - Bin Zhang
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore
| | - Zhe Liang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
| | - Chui Eng Wong
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore
| | - Benjamin Yen How See
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
| | - Hao Yu
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore
- * E-mail:
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42
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Luo X, Ou Y, Li R, He Y. Maternal transmission of the epigenetic 'memory of winter cold' in Arabidopsis. NATURE PLANTS 2020; 6:1211-1218. [PMID: 32958896 DOI: 10.1038/s41477-020-00774-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 08/24/2020] [Indexed: 05/11/2023]
Abstract
Some plants can 'remember' past environmental experience to become adapted to a given environment. For instance, after experiencing prolonged low-temperature exposure in winter (winter cold), vernalization-responsive plants remember past cold experience when temperature rises in spring, to acquire competence to flower at a later season favourable for seed production1,2. In Arabidopsis thaliana, prolonged cold induces silencing of the potent floral repressor FLOWERING LOCUS C (FLC) by Polycomb group (PcG) chromatin modifiers. This Polycomb-repressed chromatin state is epigenetically maintained and thus 'memorized' in subsequent growth and development upon return to warmth1,3. 'Memory of winter cold' has been viewed as being mitotically stable but meiotically unstable3-5, and thus not to be transmitted intergenerationally. In general, whether and how chromatin-mediated environmental memories are transmitted across generations are unknown in plants. Here, we show that the cold-induced Polycomb-repressed chromatin state at FLC or memory of winter cold is maintained in the egg cell, that is meiotically stable in the process of female gamete formation, and provide evidence that this Polycomb-mediated memory is not maintained in the sperm cell. Moreover, we show that this cold memory is inherited maternally but not paternally to the zygote and early embryos. Our study demonstrates and further provides mechanistic insights into intergenerational transmission of chromatin state-mediated environmental memories in plants.
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Affiliation(s)
- Xiao Luo
- Shanghai Center for Plant Stress Biology & National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai, China
| | - Yang Ou
- Shanghai Center for Plant Stress Biology & National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Renjie Li
- Shanghai Center for Plant Stress Biology & National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai, China
- School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Yuehui He
- Shanghai Center for Plant Stress Biology & National Key Laboratory of Plant Molecular Genetics, Chinese Academy of Sciences Center for Excellence in Molecular Plant Sciences, Shanghai, China.
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Zhang Z, Conner J, Guo Y, Ozias-Akins P. Haploidy in Tobacco Induced by PsASGR-BBML Transgenes via Parthenogenesis. Genes (Basel) 2020; 11:E1072. [PMID: 32932590 PMCID: PMC7564442 DOI: 10.3390/genes11091072] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/10/2020] [Accepted: 09/10/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Engineering apomixis in sexually reproducing plants has been long desired because of the potential to fix hybrid vigor. Validating the functionality of genes originated from apomictic species that contribute to apomixis upon transfer to sexually reproducing species is an important step. The PsASGR-BABYBOOM-like (PsASGR-BBML) gene from Pennisetum squamulatum confers parthenogenesis in this apomict, and its functionality was demonstrated in several sexually reproducing monocots but not in any dicots. METHODS We introduced the PsASGR-BBML gene regulated by egg cell-specific promoters, either AtDD45 or AtRKD2, into tobacco, and analyzed progeny of the transgenic lines resulting from self-pollination and crossing by flow cytometry. RESULTS We identified haploid progeny at a frequency lower than 1% in the AtDD45pro lines, while at a frequency of 9.3% for an octoploid (2n = 8x) AtRKD2pro line. Haploid production in the T2 generation, derived from the tetraploid T1 offspring of this original octoploid AtRKD2pro line, was also observed. Pollinated by homozygous transgenic tobacco carrying a DsRed marker gene, 4x progeny of the AtRKD2pro line yielded parthenogenetic embryos identified as DsRed negative. We verified that the DsRed negative seedlings recovered were haploid (2x). CONCLUSION The PsASGR-BBML gene regulated by egg cell-specific promoters could enable parthenogenesis in tobacco, a dicotyledon species.
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Affiliation(s)
| | | | | | - Peggy Ozias-Akins
- Department of Horticulture and Institute of Plant Breeding, Genetics & Genomics, University of Georgia, Tifton, GA 31793, USA; (Z.Z.); (J.C.); (Y.G.)
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44
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Mou W, Kao YT, Michard E, Simon AA, Li D, Wudick MM, Lizzio MA, Feijó JA, Chang C. Ethylene-independent signaling by the ethylene precursor ACC in Arabidopsis ovular pollen tube attraction. Nat Commun 2020; 11:4082. [PMID: 32796832 PMCID: PMC7429864 DOI: 10.1038/s41467-020-17819-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 07/20/2020] [Indexed: 11/09/2022] Open
Abstract
The phytohormone ethylene has numerous effects on plant growth and development. Its immediate precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), is a non-proteinogenic amino acid produced by ACC SYNTHASE (ACS). ACC is often used to induce ethylene responses. Here, we demonstrate that ACC exhibits ethylene-independent signaling in Arabidopsis thaliana reproduction. By analyzing an acs octuple mutant with reduced seed set, we find that ACC signaling in ovular sporophytic tissue is involved in pollen tube attraction, and promotes secretion of the pollen tube chemoattractant LURE1.2. ACC activates Ca2+-containing ion currents via GLUTAMATE RECEPTOR-LIKE (GLR) channels in root protoplasts. In COS-7 cells expressing moss PpGLR1, ACC induces the highest cytosolic Ca2+ elevation compared to all twenty proteinogenic amino acids. In ovules, ACC stimulates transient Ca2+ elevation, and Ca2+ influx in octuple mutant ovules rescues LURE1.2 secretion. These findings uncover a novel ACC function and provide insights for unraveling new physiological implications of ACC in plants.
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Affiliation(s)
- Wangshu Mou
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA.,Division of Crop Biotechnics, Department of Biosystems, University of Leuven, Leuven, Belgium
| | - Yun-Ting Kao
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Erwan Michard
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Alexander A Simon
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Dongdong Li
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA.,Division of Crop Biotechnics, Department of Biosystems, University of Leuven, Leuven, Belgium
| | - Michael M Wudick
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA.,Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Michael A Lizzio
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - José A Feijó
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA.
| | - Caren Chang
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA.
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45
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Song Q, Ando A, Jiang N, Ikeda Y, Chen ZJ. Single-cell RNA-seq analysis reveals ploidy-dependent and cell-specific transcriptome changes in Arabidopsis female gametophytes. Genome Biol 2020; 21:178. [PMID: 32698836 PMCID: PMC7375004 DOI: 10.1186/s13059-020-02094-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 07/06/2020] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Polyploidy provides new genetic material that facilitates evolutionary novelty, species adaptation, and crop domestication. Polyploidy often leads to an increase in cell or organism size, which may affect transcript abundance or transcriptome size, but the relationship between polyploidy and transcriptome changes remains poorly understood. Plant cells often undergo endoreduplication, confounding the polyploid effect. RESULTS To mitigate these effects, we select female gametic cells that are developmentally stable and void of endoreduplication. Using single-cell RNA sequencing (scRNA-seq) in Arabidopsis thaliana tetraploid lines and isogenic diploids, we show that transcriptome abundance doubles in the egg cell and increases approximately 1.6-fold in the central cell, consistent with cell size changes. In the central cell of tetraploid plants, DEMETER (DME) is upregulated, which can activate PRC2 family members FIS2 and MEA, and may suppress the expression of other genes. Upregulation of cell size regulators in tetraploids, including TOR and OSR2, may increase the size of reproductive cells. In diploids, the order of transcriptome abundance is central cell, synergid cell, and egg cell, consistent with their cell size variation. Remarkably, we uncover new sets of female gametophytic cell-specific transcripts with predicted biological roles; the most abundant transcripts encode families of cysteine-rich peptides, implying roles in cell-cell recognition during double fertilization. CONCLUSIONS Transcriptome in single cells doubles in tetraploid plants compared to diploid, while the degree of change and relationship to the cell size depends on cell types. These scRNA-seq resources are free of cross-contamination and are uniquely valuable for advancing plant hybridization, reproductive biology, and polyploid genomics.
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Affiliation(s)
- Qingxin Song
- Department of Molecular Biosciences, The University of Texas at Austin, 1 University Station A5000, Austin, TX, 78712, USA
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China
| | - Atsumi Ando
- Department of Molecular Biosciences, The University of Texas at Austin, 1 University Station A5000, Austin, TX, 78712, USA
| | - Ning Jiang
- Department of Biomedical Engineering, The University of Texas at Austin, 1 University Station C0800, Austin, TX, 78712, USA
| | - Yoko Ikeda
- Institute of Plant Science and Resources, Okayama University, Chuo 2-20-1, Kurashiki, Okayama, 710-0046, Japan
| | - Z Jeffrey Chen
- Department of Molecular Biosciences, The University of Texas at Austin, 1 University Station A5000, Austin, TX, 78712, USA.
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46
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Toda E, Okamoto T. Gene Expression and Genome Editing Systems by Direct Delivery of Macromolecules Into Rice Egg Cells and Zygotes. Bio Protoc 2020; 10:e3681. [PMID: 33659352 PMCID: PMC7842353 DOI: 10.21769/bioprotoc.3681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 05/05/2020] [Accepted: 05/09/2020] [Indexed: 11/02/2022] Open
Abstract
Polyethylene glycol calcium (PEG-Ca2+)-mediated transfection allows rapid and efficient examination to analyze diverse cellular functions of genes of interest. In plant cells, macromolecules, such as DNA, RNA and protein, are delivered into protoplasts derived from somatic tissues or calli via PEG-Ca2+ transfection. To broaden and develop the scope of investigations using plant gametes and zygotes, a procedure for direct delivery of macromolecules into these cells has recently been established using PEG-Ca2+ transfection. This PEG-Ca2+-mediated delivery into rice egg cells/zygotes consists of four microtechniques, (i) isolation of gametes, (ii) production of zygotes by electrofusion of gametes, (iii) PEG-Ca2+-mediated delivery of macromolecules into isolated egg cells or produced zygotes, and (iv) culture and subsequent analyses of the transfected egg cells/zygotes. Because the full protocol for microtechniques (i) and (ii) have already been reported in Toda et al., 2016 , microtechniques (iii) and (iv) are mainly described in this protocol.
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Affiliation(s)
- Erika Toda
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, 192-0397, Japan
| | - Takashi Okamoto
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, 192-0397, Japan
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47
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Chen D, Wang Y, Zhang W, Li N, Dai B, Xie F, Sun Y, Sun M, Peng X. Gametophyte-specific DEAD-box RNA helicase 29 is required for functional maturation of male and female gametophytes in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:4083-4092. [PMID: 32280991 DOI: 10.1093/jxb/eraa190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/10/2020] [Indexed: 06/11/2023]
Abstract
The maturation of male and female gametophytes together with its impact on plant sexual reproduction has not received much attention, and the molecular mechanisms underlying the process are largely unknown. Here, we show that Arabidopsis DEAD-box RNA helicase 29 (RH29) is critical for the functional maturation of both male and female gametophytes. Homozygous rh29 mutants could not be obtained, and heterozygous mutant plants were semi-sterile. Progression of the cell cycle in rh29 female gametophytes was delayed. Delayed pollination experiments showed that rh29 female gametophytes underwent cell-fate specification but were unable to develop into functional gametophytes. Functional specification but not morphogenesis was also disrupted in rh29 male gametophytes, causing defective pollen tube growth in the pistil. RH29 was highly and specifically expressed in gametophytic cells. RH29 shares high amino acid sequence identity with yeast Dbp10p, which partially rescues the aborted-ovules phenotype of rh29/RH29 plants. RH29 is essential for the synthesis of REGULATORY PARTICLE TRIPLE A ATPase 5a (RPT5a), a subunit of the regulatory particle of the 26S proteasome. Our results suggest that gametophyte functional maturation is a necessary process for successful fertilization and that RH29 is essential for the functional maturation of both male and female gametophytes.
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Affiliation(s)
- Dan Chen
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yameng Wang
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Wen Zhang
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Na Li
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Bo Dai
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Fei Xie
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yang Sun
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Mengxiang Sun
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiongbo Peng
- State Key Laboratory for Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
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48
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Min Y, Frost JM, Choi Y. Gametophytic Abortion in Heterozygotes but Not in Homozygotes: Implied Chromosome Rearrangement during T-DNA Insertion at the ASF1 Locus in Arabidopsis. Mol Cells 2020; 43:448-458. [PMID: 32259880 PMCID: PMC7264478 DOI: 10.14348/molcells.2020.2290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 03/05/2020] [Accepted: 03/08/2020] [Indexed: 12/24/2022] Open
Abstract
T-DNA insertional mutations in Arabidopsis genes have conferred huge benefits to the research community, greatly facilitating gene function analyses. However, the insertion process can cause chromosomal rearrangements. Here, we show an example of a likely rearrangement following T-DNA insertion in the Anti-Silencing Function 1B (ASF1B) gene locus on Arabidopsis chromosome 5, so that the phenotype was not relevant to the gene of interest, ASF1B. ASF1 is a histone H3/H4 chaperone involved in chromatin remodeling in the sporophyte and during reproduction. Plants that were homozygous for mutant alleles asf1a or asf1b were developmentally normal. However, following self-fertilization of double heterozygotes (ASF1A/asf1a ASF1B/asf1b, hereafter AaBb), defects were visible in both male and female gametes. Half of the AaBb and aaBb ovules displayed arrested embryo sacs with functional megaspore identity. Similarly, half of the AaBb and aaBb pollen grains showed centromere defects, resulting in pollen abortion at the bi-cellular stage of the male gametophyte. However, inheritance of the mutant allele in a given gamete did not solely determine the abortion phenotype. Introducing functional ASF1B failed to rescue the AaBb- and aaBb- mediated abortion, suggesting that heterozygosity in the ASF1B gene causes gametophytic defects, rather than the loss of ASF1. The presence of reproductive defects in heterozygous mutants but not in homozygotes, and the characteristic all-or-nothing pollen viability within tetrads, were both indicative of commonly-observed T-DNA-mediated translocation activity for this allele. Our observations reinforce the importance of complementation tests in assigning gene function using reverse genetics.
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Affiliation(s)
- Yunsook Min
- Department of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Jennifer M. Frost
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 9470, USA
- Present address: Genomics and Child Health, Queen Mary University of London, London E1 2AT, United Kingdom
| | - Yeonhee Choi
- Department of Biological Sciences, Seoul National University, Seoul 08826, Korea
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Warman C, Panda K, Vejlupkova Z, Hokin S, Unger-Wallace E, Cole RA, Chettoor AM, Jiang D, Vollbrecht E, Evans MMS, Slotkin RK, Fowler JE. High expression in maize pollen correlates with genetic contributions to pollen fitness as well as with coordinated transcription from neighboring transposable elements. PLoS Genet 2020; 16:e1008462. [PMID: 32236090 PMCID: PMC7112179 DOI: 10.1371/journal.pgen.1008462] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 02/27/2020] [Indexed: 12/20/2022] Open
Abstract
In flowering plants, gene expression in the haploid male gametophyte (pollen) is essential for sperm delivery and double fertilization. Pollen also undergoes dynamic epigenetic regulation of expression from transposable elements (TEs), but how this process interacts with gene expression is not clearly understood. To explore relationships among these processes, we quantified transcript levels in four male reproductive stages of maize (tassel primordia, microspores, mature pollen, and sperm cells) via RNA-seq. We found that, in contrast with vegetative cell-limited TE expression in Arabidopsis pollen, TE transcripts in maize accumulate as early as the microspore stage and are also present in sperm cells. Intriguingly, coordinate expression was observed between highly expressed protein-coding genes and their neighboring TEs, specifically in mature pollen and sperm cells. To investigate a potential relationship between elevated gene transcript level and pollen function, we measured the fitness cost (male-specific transmission defect) of GFP-tagged coding sequence insertion mutations in over 50 genes identified as highly expressed in the pollen vegetative cell, sperm cell, or seedling (as a sporophytic control). Insertions in seedling genes or sperm cell genes (with one exception) exhibited no difference from the expected 1:1 transmission ratio. In contrast, insertions in over 20% of vegetative cell genes were associated with significant reductions in fitness, showing a positive correlation of transcript level with non-Mendelian segregation when mutant. Insertions in maize gamete expressed2 (Zm gex2), the sole sperm cell gene with measured contributions to fitness, also triggered seed defects when crossed as a male, indicating a conserved role in double fertilization, given the similar phenotype previously demonstrated for the Arabidopsis ortholog GEX2. Overall, our study demonstrates a developmentally programmed and coordinated transcriptional activation of TEs and genes in pollen, and further identifies maize pollen as a model in which transcriptomic data have predictive value for quantitative phenotypes.
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Affiliation(s)
- Cedar Warman
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Kaushik Panda
- Donald Danforth Plant Science Center, St. Louis, Missouri, United States of America
| | - Zuzana Vejlupkova
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Sam Hokin
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California, United States of America
| | - Erica Unger-Wallace
- Department of Genetics Development and Cell Biology, Iowa State University, Ames, Iowa, United States of America
| | - Rex A. Cole
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Antony M. Chettoor
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California, United States of America
| | - Duo Jiang
- Department of Statistics, Oregon State University, Corvallis, Oregon, United States of America
| | - Erik Vollbrecht
- Department of Genetics Development and Cell Biology, Iowa State University, Ames, Iowa, United States of America
- Bioinformatics and Computational Biology, Iowa State University, Ames, Iowa, United States of America
- Interdepartmental Genetics, Iowa State University, Ames, Iowa, United States of America
| | - Matthew M. S. Evans
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California, United States of America
| | - R. Keith Slotkin
- Donald Danforth Plant Science Center, St. Louis, Missouri, United States of America
| | - John E. Fowler
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
- Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon, United States of America
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50
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Fíla J, Klodová B, Potěšil D, Juříček M, Šesták P, Zdráhal Z, Honys D. The beta Subunit of Nascent Polypeptide Associated Complex Plays A Role in Flowers and Siliques Development of Arabidopsis thaliana. Int J Mol Sci 2020; 21:E2065. [PMID: 32192231 PMCID: PMC7139743 DOI: 10.3390/ijms21062065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/11/2020] [Accepted: 03/14/2020] [Indexed: 01/06/2023] Open
Abstract
The nascent polypeptide-associated (NAC) complex was described in yeast as a heterodimer composed of two subunits, α and β, and was shown to bind to the nascent polypeptides newly emerging from the ribosomes. NAC function was widely described in yeast and several information are also available about its role in plants. The knock down of individual NAC subunit(s) led usually to a higher sensitivity to stress. In Arabidopsis thaliana genome, there are five genes encoding NACα subunit, and two genes encoding NACβ. Double homozygous mutant in both genes coding for NACβ was acquired, which showed a delayed development compared to the wild type, had abnormal number of flower organs, shorter siliques and greatly reduced seed set. Both NACβ genes were characterized in more detail-the phenotype of the double homozygous mutant was complemented by a functional NACβ copy. Then, both NACβ genes were localized to nuclei and cytoplasm and their promoters were active in many organs (leaves, cauline leaves, flowers, pollen grains, and siliques together with seeds). Since flowers were the most affected organs by nacβ mutation, the flower buds' transcriptome was identified by RNA sequencing, and their proteome by gel-free approach. The differential expression analyses of transcriptomic and proteomic datasets suggest the involvement of NACβ subunits in stress responses, male gametophyte development, and photosynthesis.
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Affiliation(s)
- Jan Fíla
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Praha 6, Czech Republic; (B.K.); (D.H.)
| | - Božena Klodová
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Praha 6, Czech Republic; (B.K.); (D.H.)
- Department of Experimental Plant Biology, Faculty of Science, Charles University, 12800 Praha 2, Czech Republic
| | - David Potěšil
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic; (D.P.); (Z.Z.)
| | - Miloslav Juříček
- Station of Apple Breeding for Disease Resistance, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Praha 6, Czech Republic;
| | - Petr Šesták
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Praha 6, Czech Republic; (B.K.); (D.H.)
- Department of Experimental Plant Biology, Faculty of Science, Charles University, 12800 Praha 2, Czech Republic
| | - Zbyněk Zdráhal
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, 62500 Brno, Czech Republic; (D.P.); (Z.Z.)
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, 16502 Praha 6, Czech Republic; (B.K.); (D.H.)
- Department of Experimental Plant Biology, Faculty of Science, Charles University, 12800 Praha 2, Czech Republic
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