1
|
Lan Z, Zhong S, Qu LJ. Plant reproduction: Seed size gated by central cell fertilization. Curr Biol 2025; 35:R389-R391. [PMID: 40393403 DOI: 10.1016/j.cub.2025.03.078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2025]
Abstract
Double fertilization produces the embryo and endosperm, the primary components of a seed. A recent study shows how central cell fertilization specifically initiates the opening of a vascular gate to ensure efficient allocation of maternal resources for optimal seed development.
Collapse
Affiliation(s)
- Zijun Lan
- State Key Laboratory for Gene Function and Modulation Research, Peking-Tsinghua Center for Life Sciences, New Cornerstone Science Laboratory, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Sheng Zhong
- State Key Laboratory for Gene Function and Modulation Research, Peking-Tsinghua Center for Life Sciences, New Cornerstone Science Laboratory, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China.
| | - Li-Jia Qu
- State Key Laboratory for Gene Function and Modulation Research, Peking-Tsinghua Center for Life Sciences, New Cornerstone Science Laboratory, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China.
| |
Collapse
|
2
|
Liu X, Nakajima KP, Adhikari PB, Wu X, Zhu S, Okada K, Kagenishi T, Kurotani KI, Ishida T, Nakamura M, Sato Y, Kawakatsu Y, Xie L, Huang C, He J, Yokawa K, Sawa S, Higashiyama T, Bradford KJ, Notaguchi M, Kasahara RD. Fertilization-dependent phloem end gate regulates seed size. Curr Biol 2025; 35:2049-2063.e3. [PMID: 40199323 DOI: 10.1016/j.cub.2025.03.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2024] [Revised: 01/09/2025] [Accepted: 03/17/2025] [Indexed: 04/10/2025]
Abstract
Seed formation is essential for plant propagation and food production. We present a novel mechanism for the regulation of seed size by a newly identified "gate" at the chalazal end of the ovule regulating nutrient transport into the developing seed. This gate is blocked by callose deposition in unfertilized mature ovules (closed state), but the callose is removed after central cell fertilization, allowing nutrient transport into the seed (open state). However, if fertilization fails, callose deposition persists, preventing transportation of nutrients from the funiculus. A mutant in an ovule-expressed β-1,3-glucanase gene (AtBG_ppap) showed incomplete callose degradation after fertilization and produced smaller seeds, apparently due to its partially closed state. By contrast, an AtBG_ppap overexpression line produced larger seeds due to continuous callose degradation, fully opening the gate for nutrient transport into the seed. The mechanism was also identified in rice, indicating that it potentially could be applied widely to angiosperms to increase seed size.
Collapse
Affiliation(s)
- Xiaoyan Liu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Kohdai P Nakajima
- Department of Biology, Technion-Institute of Technology, Haifa 320000, Israel
| | - Prakash Babu Adhikari
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Xiaoyan Wu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Shaowei Zhu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Kentaro Okada
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Tomoko Kagenishi
- Faculty of Engineering, Kitami Institute of Technology, 165 Koen-cho, Kitami, Hokkaido 090-8507, Japan
| | - Ken-Ichi Kurotani
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Takashi Ishida
- Graduate School of Science & Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan; International Research Organization for Advanced Science and Technology (IROAST), Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - Masayoshi Nakamura
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-chou, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Yoshikatsu Sato
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-chou, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Yaichi Kawakatsu
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan
| | - Liyang Xie
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Chen Huang
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Jiale He
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Ken Yokawa
- Faculty of Engineering, Kitami Institute of Technology, 165 Koen-cho, Kitami, Hokkaido 090-8507, Japan
| | - Shinichiro Sawa
- Graduate School of Science & Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan; International Research Organization for Advanced Science and Technology (IROAST), Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - Tetsuya Higashiyama
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kent J Bradford
- Department of Plant Sciences, Seed Biotechnology Center, University of California, Davis, Davis, CA 95616, USA
| | - Michitaka Notaguchi
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan; Department of Botany, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Kyoto 606-8502, Japan.
| | - Ryushiro D Kasahara
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan.
| |
Collapse
|
3
|
Zhong S, Lan Z, Qu LJ. Ingenious Male-Female Communication Ensures Successful Double Fertilization in Angiosperms. ANNUAL REVIEW OF PLANT BIOLOGY 2025; 76:401-431. [PMID: 39952677 DOI: 10.1146/annurev-arplant-083123-071512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2025]
Abstract
The colonization of land by plants marked a pivotal transformation in terrestrial ecosystems. In order to adapt to the terrestrial environment, angiosperms, which dominate the terrestrial flora with around 300,000 species, have evolved sophisticated mechanisms for sexual reproduction involving intricate interactions between male and female structures, starting from pollen deposition on the stigma and culminating in double fertilization within the ovule. The pollen tube plays a crucial role by navigating through female tissues to deliver sperm cells. The molecular intricacies of these male-female interactions, involving numerous signaling pathways and regulatory proteins, have been extensively studied over the past two decades. This review summarizes recent findings on the regulatory mechanisms of these male-female interactions in angiosperms. We aim to provide a comprehensive understanding of plant reproductive biology and highlight the implications of these mechanisms for crop improvement and the development of new agricultural technologies.
Collapse
Affiliation(s)
- Sheng Zhong
- State Key Laboratory of Gene Function and Modulation Research, Peking-Tsinghua Center for Life Sciences, New Cornerstone Science Laboratory, College of Life Sciences, Peking University, Beijing, China;
| | - Zijun Lan
- State Key Laboratory of Gene Function and Modulation Research, Peking-Tsinghua Center for Life Sciences, New Cornerstone Science Laboratory, College of Life Sciences, Peking University, Beijing, China;
| | - Li-Jia Qu
- State Key Laboratory of Gene Function and Modulation Research, Peking-Tsinghua Center for Life Sciences, New Cornerstone Science Laboratory, College of Life Sciences, Peking University, Beijing, China;
| |
Collapse
|
4
|
Hirano T, Murata M, Watarikawa Y, Hoshino Y, Abe T, Kunitake H. Distinctive development of embryo and endosperm caused by male gametes irradiated with carbon-ion beam. PLANT REPRODUCTION 2024; 37:355-363. [PMID: 38332356 PMCID: PMC11377488 DOI: 10.1007/s00497-024-00496-9] [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: 10/22/2023] [Accepted: 01/10/2024] [Indexed: 02/10/2024]
Abstract
KEY MESSAGE In Cyrtanthus mackenii, development of embryo and endosperm were differentially affected by fertilization of male gametes with DNA damage and mutations. Pollen irradiation with ionizing radiations has been applied in plant breeding and genetic research, and haploid plant induction has mainly been performed by male inactivation with high-dose irradiation. However, the fertilization process of irradiated male gametes and the early development of embryo and endosperm have not received much attention. Heavy-ion beams, a type of radiation, have been widely applied as effective mutagens for plants and show a high mutation rate even at low-dose irradiation. In this study, we analyzed the effects of male gametes of Cyrtanthus mackenii irradiated with a carbon-ion beam at low doses on fertilization. In immature seeds derived from the pollination of irradiated pollen grains, two types of embryo sacs were observed: embryo sac with a normally developed embryo and endosperm and embryo sac with an egg cell or an undivided zygote and an endosperm. Abnormalities in chromosome segregation, such as chromosomal bridges, were observed only in the endosperm nuclei, irrespective of the presence or absence of embryogenesis. Therefore, in Cyrtanthus, embryogenesis is strongly affected by DNA damage or mutations in male gametes. Moreover, various DNA contents were detected in the embryo and endosperm nuclei, and endoreduplication may have occurred in the endosperm nuclei. As carbon-ion irradiation causes chromosomal rearrangements even at low doses, pollen irradiation can be an interesting tool for studying double fertilization and mutation heritability.
Collapse
Affiliation(s)
- Tomonari Hirano
- Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai Nishi, Miyazaki, 889-2192, Japan.
- Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
| | - Muneaki Murata
- Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai Nishi, Miyazaki, 889-2192, Japan
| | - Yurie Watarikawa
- Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai Nishi, Miyazaki, 889-2192, Japan
| | - Yoichiro Hoshino
- Field Science Center for Northern Biosphere, Hokkaido University, Kita 11, Nishi 10, Kita-ku, Sapporo, 060-0811, Japan
| | - Tomoko Abe
- Nishina Center for Accelerator-Based Science, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Hisato Kunitake
- Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-Kibanadai Nishi, Miyazaki, 889-2192, Japan
| |
Collapse
|
5
|
Qiu R, Liu Y, Cai Z, Li J, Wu C, Wang G, Lin C, Peng Y, Deng Z, Tang W, Wu W, Duan Y. Glucan Synthase-like 2 is Required for Seed Initiation and Filling as Well as Pollen Fertility in Rice. RICE (NEW YORK, N.Y.) 2023; 16:44. [PMID: 37804355 PMCID: PMC10560172 DOI: 10.1186/s12284-023-00662-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 09/25/2023] [Indexed: 10/09/2023]
Abstract
BACKGROUND The Glucan synthase-like (GSL) genes are indispensable for some important highly-specialized developmental and cellular processes involving callose synthesis and deposition in plants. At present, the best-characterized reproductive functions of GSL genes are those for pollen formation and ovary expansion, but their role in seed initiation remains unknown. RESULTS We identified a rice seed mutant, watery seed 1-1 (ws1-1), which contained a mutation in the OsGSL2 gene. The mutant produced seeds lacking embryo and endosperm but filled with transparent and sucrose-rich liquid. In a ws1-1 spikelet, the ovule development was normal, but the microsporogenesis and male gametophyte development were compromised, resulting in the reduction of fertile pollen. After fertilization, while the seed coat normally developed, the embryo failed to differentiate normally. In addition, the divided endosperm-free nuclei did not migrate to the periphery of the embryo sac but aggregated so that their proliferation and cellularization were arrested. Moreover, the degeneration of nucellus cells was delayed in ws1-1. OsGSL2 is highly expressed in reproductive organs and developing seeds. Disrupting OsGSL2 reduced callose deposition on the outer walls of the microspores and impaired the formation of the annular callose sheath in developing caryopsis, leading to pollen defect and seed abortion. CONCLUSIONS Our findings revealed that OsGSL2 is essential for rice fertility and is required for embryo differentiation and endosperm-free nucleus positioning, indicating a distinct role of OsGSL2, a callose synthase gene, in seed initiation, which provides new insight into the regulation of seed development in cereals.
Collapse
Affiliation(s)
- Ronghua Qiu
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Yang Liu
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Zhengzheng Cai
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Jieqiong Li
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Chunyan Wu
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Gang Wang
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Chenchen Lin
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Yulin Peng
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Zhanlin Deng
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Weiqi Tang
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Weiren Wu
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
| | - Yuanlin Duan
- Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
- Fujian Key Laboratory of Crop Breeding By Design, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
| |
Collapse
|
6
|
Liu X, Adhikari PB, Kasahara RD. Pollen Tube Content Facilitates and Increases the Potential of Endosperm Proliferation Irrespective of Fertilization in <i>Arabidopsis thaliana</i>. CYTOLOGIA 2023. [DOI: 10.1508/cytologia.88.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
|
7
|
Takasaki H, Ikeda M, Hasegawa R, Zhang Y, Sakamoto S, Maruyama D, Mitsuda N, Kinoshita T, Ohme-Takagi M. Elongation of Siliques Without Pollination 3 Regulates Nutrient Flow Necessary for Embryogenesis. PLANT & CELL PHYSIOLOGY 2023; 64:117-123. [PMID: 36264192 DOI: 10.1093/pcp/pcac151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 10/17/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Apomixis, defined as the transfer of maternal germplasm to offspring without fertilization, enables the fixation of F1-useful traits, providing advantages in crop breeding. However, most apomictic plants require pollination to produce the endosperm. The endosperm is essential for embryogenesis, and its development is suppressed until fertilization. We show that the expression of a chimeric repressor of the Elongation of Siliques without Pollination 3 (ESP3) gene (Pro35S:ESP3-SRDX) induces ovule enlargement without fertilization in Arabidopsis thaliana. The ESP3 gene encodes a protein similar to the flowering Wageningen homeodomain transcription factor containing a StAR-related lipid transfer domain. However, ESP3 lacks the homeobox-encoding region. Genes related to the cell cycle and sugar metabolism were upregulated in unfertilized Pro35S:ESP3-SRDX ovules similar to those in fertilized seeds, while those related to autophagy were downregulated similar to those in fertilized seeds. Unfertilized Pro35S:ESP3-SRDX ovules partially nourished embryos when only the egg was fertilized, accumulating hexoses without central cell proliferation. ESP3 may regulate nutrient flow during seed development, and ESP3-SRDX could be a useful tool for complete apomixis that does not require pseudo-fertilization.
Collapse
Affiliation(s)
- Hironori Takasaki
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570 Japan
| | - Miho Ikeda
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570 Japan
- Department of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Matsuoka-Kenjojima, Eiheiji-cho, Fukui, 910-1195 Japan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8570 Japan
| | - Reika Hasegawa
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570 Japan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8570 Japan
| | - Yilin Zhang
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570 Japan
| | - Shingo Sakamoto
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8570 Japan
| | - Daisuke Maruyama
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka-cho, Toksuka-ku, Yokohama, Kanagawa, 244-0813 Japan
| | - Nobutaka Mitsuda
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki, 305-8570 Japan
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka-cho, Toksuka-ku, Yokohama, Kanagawa, 244-0813 Japan
| | - Masaru Ohme-Takagi
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570 Japan
- Institute of Tropical Plant Science and Microbiology, National Cheng Kung University, No.1, University Road, Tainan City 701, Taiwan
| |
Collapse
|
8
|
Guo L, Luo X, Li M, Joldersma D, Plunkert M, Liu Z. Mechanism of fertilization-induced auxin synthesis in the endosperm for seed and fruit development. Nat Commun 2022; 13:3985. [PMID: 35810202 PMCID: PMC9271072 DOI: 10.1038/s41467-022-31656-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 06/26/2022] [Indexed: 11/09/2022] Open
Abstract
The dominance of flowering plants on earth is owed largely to the evolution of maternal tissues such as fruit and seedcoat that protect and disseminate the seeds. The mechanism of how fertilization triggers the development of these specialized maternal tissues is not well understood. A key event is the induction of auxin synthesis in the endosperm, and the mobile auxin subsequently stimulates seedcoat and fruit development. However, the regulatory mechanism of auxin synthesis in the endosperm remains unknown. Here, we show that a type I MADS box gene AGL62 is required for the activation of auxin synthesis in the endosperm in both Fragaria vesca, a diploid strawberry, and in Arabidopsis. Several strawberry FveATHB genes were identified as downstream targets of FveAGL62 and act to repress auxin biosynthesis. In this work, we identify a key mechanism for auxin induction to mediate fertilization success, a finding broadly relevant to flowering plants. In flowering plants, fertilization triggers auxin synthesis in the endosperm to promote seed and fruit development. Here the authors show that an MADS-box transcription factor AGL62 is required to activate auxin synthesis in the endosperms of Fragaria vesca, a diploid strawberry, and Arabidopsis.
Collapse
Affiliation(s)
- Lei Guo
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Xi Luo
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Muzi Li
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Dirk Joldersma
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Madison Plunkert
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Zhongchi Liu
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA.
| |
Collapse
|
9
|
Shin S, Chairattanawat C, Yamaoka Y, Yang Q, Lee Y, Hwang JU. Early seed development requires the A-type ATP-binding cassette protein ABCA10. PLANT PHYSIOLOGY 2022; 189:360-374. [PMID: 35166840 PMCID: PMC9070825 DOI: 10.1093/plphys/kiac062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/06/2022] [Indexed: 05/11/2023]
Abstract
A-type ATP-binding cassette (ABCA) proteins transport lipids and lipid-based molecules in humans, and their malfunction is associated with various inherited diseases. Although plant genomes encode many ABCA transporters, their molecular and physiological functions remain largely unknown. Seeds are rapidly developing organs that rely on the biosynthesis and transport of large quantities of lipids to generate new membranes and storage lipids. In this study, we characterized the Arabidopsis (Arabidopsis thaliana) ABCA10 transporter, which is selectively expressed in female gametophytes and early developing seeds. By 3 d after flowering (DAF), seeds from the abca10 loss-of-function mutant exhibited a smaller chalazal endosperm than those of the wild-type. By 4 DAF, their endosperm nuclei occupied a smaller area than those of the wild-type. The endosperm nuclei of the mutants also failed to distribute evenly inside the seed coat and stayed aggregated instead, possibly due to inadequate expansion of abca10 endosperm. This endosperm defect might have retarded abca10 embryo development. At 7 DAF, a substantial portion of abca10 embryos remained at the globular or earlier developmental stages, whereas wild-type embryos were at the torpedo or later stages. ABCA10 is likely involved in lipid metabolism, as ABCA10 overexpression induced the overaccumulation of triacylglycerol but did not change the carbohydrate or protein contents in seeds. In agreement, ABCA10 localized to the endoplasmic reticulum (ER), the major site of lipid biosynthesis. Our results reveal that ABCA10 plays an essential role in early seed development, possibly by transporting substrates for lipid metabolism to the ER.
Collapse
Affiliation(s)
- Seungjun Shin
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | | | - Yasuyo Yamaoka
- Division of Biotechnology, The Catholic University of Korea, Bucheon 14662, Republic of Korea
| | - Qianying Yang
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Youngsook Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
- Department of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | | |
Collapse
|
10
|
Heydlauff J, Erbasol Serbes I, Vo D, Mao Y, Gieseking S, Nakel T, Harten T, Völz R, Hoffmann A, Groß-Hardt R. Dual and opposing roles of EIN3 reveal a generation conflict during seed growth. MOLECULAR PLANT 2022; 15:363-371. [PMID: 34848348 PMCID: PMC8837274 DOI: 10.1016/j.molp.2021.11.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/12/2021] [Accepted: 11/26/2021] [Indexed: 05/28/2023]
Abstract
Seed size critically affects grain yield of crops and hence represents a key breeding target. The development of embryo-nourishing endosperm is a key driver of seed expansion. We here report unexpected dual roles of the transcription factor EIN3 in regulating seed size. These EIN3 functions have remained largely undiscovered because they oppose each other. Capitalizing on the analysis of multiple ethylene biosynthesis mutants, we demonstrate that EIN3 represses endosperm and seed development in a pathway regulated by ethylene. We, in addition, provide evidence that EIN3-mediated synergid nucleus disintegration promotes endosperm expansion. Interestingly, synergid nucleus disintegration is not affected in various ethylene biosynthesis mutants, suggesting that this promoting function of EIN3 is independent of ethylene. Whereas the growth-inhibitory ethylene-dependent EIN3 action appears to be encoded by sporophytic tissue, the growth-promoting role of EIN3 is induced by fertilization, revealing a generation conflict that converges toward the key signaling component EIN3.
Collapse
Affiliation(s)
- Juliane Heydlauff
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany
| | - Isil Erbasol Serbes
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany
| | - Dieu Vo
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany
| | - Yanbo Mao
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany
| | - Sonja Gieseking
- ZMBP, University of Tübingen, Auf der Morgenstelle 32 72076 Tübingen, Germany
| | - Thomas Nakel
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany
| | - Theresa Harten
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany
| | - Ronny Völz
- ZMBP, University of Tübingen, Auf der Morgenstelle 32 72076 Tübingen, Germany
| | - Anja Hoffmann
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany
| | - Rita Groß-Hardt
- University of Bremen, Centre for Biomolecular Interactions Bremen (CBIB), Leobenerstrasse 5, 28359 Bremen, Germany.
| |
Collapse
|
11
|
Motomura K, Takeuchi H, Notaguchi M, Tsuchi H, Takeda A, Kinoshita T, Higashiyama T, Maruyama D. Persistent directional growth capability in Arabidopsis thaliana pollen tubes after nuclear elimination from the apex. Nat Commun 2021; 12:2331. [PMID: 33888710 PMCID: PMC8062503 DOI: 10.1038/s41467-021-22661-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 03/22/2021] [Indexed: 02/04/2023] Open
Abstract
During the double fertilization process, pollen tubes deliver two sperm cells to an ovule containing the female gametes. In the pollen tube, the vegetative nucleus and sperm cells move together to the apical region where the vegetative nucleus is thought to play a crucial role in controlling the direction and growth of the pollen tube. Here, we report the generation of pollen tubes in Arabidopsis thaliana whose vegetative nucleus and sperm cells are isolated and sealed by callose plugs in the basal region due to apical transport defects induced by mutations in the WPP domain-interacting tail-anchored proteins (WITs) and sperm cell-specific expression of a dominant mutant of the CALLOSE SYNTHASE 3 protein. Through pollen-tube guidance assays, we show that the physiologically anuclear mutant pollen tubes maintain the ability to grow and enter ovules. Our findings provide insight into the sperm cell delivery mechanism and illustrate the independence of the tip-localized vegetative nucleus from directional growth control of the pollen tube.
Collapse
Affiliation(s)
- Kazuki Motomura
- Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan.,Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.,JST, PRESTO, Kawaguchi, Saitama, 332-0012, Japan
| | - Hidenori Takeuchi
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.,Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Michitaka Notaguchi
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.,Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Haruna Tsuchi
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan
| | - Atsushi Takeda
- Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan.,College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan
| | - Tetsuya Higashiyama
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan.,Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.,Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Daisuke Maruyama
- Kihara Institute for Biological Research, Yokohama City University, Maioka-cho, Totsuka-ku, Yokohama, Kanagawa, 244-0813, Japan.
| |
Collapse
|
12
|
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: 30] [Impact Index Per Article: 7.5] [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.
Collapse
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)
| |
Collapse
|
13
|
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: 0.8] [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.
Collapse
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
| |
Collapse
|
14
|
Abstract
Carbohydrates (sugars) are an essential energy-source for all life forms. They take a significant share of our daily consumption and are used for biofuel production as well. However, sugarcane and sugar beet are the only two crop plants which are used to produce sugar in significant amounts. Here, we have discovered and fine-tuned a phenomenon in rice which leads them to produce sugary-grain. We knocked-out GCS1 genes in rice by using CRISPR technology, which led to fertilization failure and pollen tube-dependent ovule enlargement morphology (POEM) phenomenon. Apparently, the POEMed-like rice ovule ('endosperm-focused') can grow near-normal seed-size unlike earlier observations in Arabidopsis in which gcs1 ovules ('embryo-focused') were aborted quite early. The POEMed-like rice ovules contained 10-20% sugar, with extremely high sucrose content (98%). Trancriptomic analysis revealed that the osgcs1 ovules had downregulation of starch biosynthetic genes, which would otherwise have converted sucrose to starch. Overall, this study shows that pollen tube content release is sufficient to trigger sucrose unloading at rice ovules. However, successful fertilization is indispensable to trigger sucrose-starch conversion. These findings are expected to pave the way for developing novel sugar producing crops suited for diverse climatic regions.
Collapse
|
15
|
Adhikari PB, Liu X, Kasahara RD. Mechanics of Pollen Tube Elongation: A Perspective. FRONTIERS IN PLANT SCIENCE 2020; 11:589712. [PMID: 33193543 PMCID: PMC7606272 DOI: 10.3389/fpls.2020.589712] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/30/2020] [Indexed: 05/13/2023]
Abstract
Pollen tube (PT) serves as a vehicle that delivers male gametes (sperm cells) to a female gametophyte during double fertilization, which eventually leads to the seed formation. It is one of the fastest elongating structures in plants. Normally, PTs traverse through the extracellular matrix at the transmitting tract after penetrating the stigma. While the endeavor may appear simple, the molecular processes and mechanics of the PT elongation is yet to be fully resolved. Although it is the most studied "tip-growing" structure in plants, several features of the structure (e.g., Membrane dynamics, growth behavior, mechanosensing etc.) are only partially understood. In many aspects, PTs are still considered as a tissue rather than a "unique cell." In this review, we have attempted to discuss mainly on the mechanics behind PT-elongation and briefly on the molecular players involved in the process. Four aspects of PTs are particularly discussed: the PT as a cell, its membrane dynamics, mechanics of its elongation, and the potential mechanosensors involved in its elongation based on relevant findings in both plant and non-plant models.
Collapse
Affiliation(s)
- Prakash Babu Adhikari
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaoyan Liu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, China
| | - Ryushiro D. Kasahara
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, China
| |
Collapse
|
16
|
Adhikari PB, Liu X, Kasahara RD. Fertilization-Defective Gametophytic Mutant Screening: A Novel Approach. FRONTIERS IN PLANT SCIENCE 2020; 11:967. [PMID: 32714355 PMCID: PMC7340155 DOI: 10.3389/fpls.2020.00967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Gametophytic mutants share very small proportion of the total mutants generated by any mutagenic approach; even rarer are the fertilization-defective gametophytic mutants. They require an efficient and targeted strategy instead of 'brute force' screening approach. The classical gametophyte mutant screening method, mainly based on the segregation distortion, can distinguish gametophytic mutants from the others. However, the mutants pooled after the screening constitute both fertilization-defective and developmental-defective gametophytic mutants. Until recently, there has not been any straightforward way to screen the former from the latter. Additionally, most of the mutations affecting both gametes are lost during the screening process. The novel gametophyte screening approach tends to circumvent those shortcomings. This review discusses on the classical approach of gametophytic mutant screening and focuses on the novel approach on distinguishing fertilization-/developmental-defective gametophytic mutants (both male and female). It offers an empirical basis of screening such mutants by taking in the consideration of earlier studies on fertilization failure, initiation of seed coat formation, and fertilization recovery system in plants.
Collapse
Affiliation(s)
- Prakash Babu Adhikari
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaoyan Liu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, China
| | - Ryushiro D. Kasahara
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, China
| |
Collapse
|
17
|
Adhikari PB, Liu X, Wu X, Zhu S, Kasahara RD. Fertilization in flowering plants: an odyssey of sperm cell delivery. PLANT MOLECULAR BIOLOGY 2020; 103:9-32. [PMID: 32124177 DOI: 10.1007/s11103-020-00987-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 02/26/2020] [Indexed: 05/22/2023]
Abstract
In light of the available discoveries in the field, this review manuscript discusses on plant reproduction mechanism and molecular players involved in the process. Sperm cells in angiosperms are immotile and are physically distant to the female gametophytes (FG). To secure the production of the next generation, plants have devised a clever approach by which the two sperm cells in each pollen are safely delivered to the female gametophyte where two fertilization events occur (by each sperm cell fertilizing an egg cell and central cell) to give rise to embryo and endosperm. Each of the successfully fertilized ovules later develops into a seed. Sets of macromolecules play roles in pollen tube (PT) guidance, from the stigma, through the transmitting tract and funiculus to the micropylar end of the ovule. Other sets of genetic players are involved in PT reception and in its rupture after it enters the ovule, and yet other sets of genes function in gametic fusion. Angiosperms have come long way from primitive reproductive structure development to today's sophisticated, diverse, and in most cases flamboyant organ. In this review, we will be discussing on the intricate yet complex molecular mechanism of double fertilization and how it might have been shaped by the evolutionary forces focusing particularly on the model plant Arabidopsis.
Collapse
Affiliation(s)
- Prakash B Adhikari
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Xiaoyan Liu
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Xiaoyan Wu
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Shaowei Zhu
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Ryushiro D Kasahara
- College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
- Horticultural Plant Biology and Metabolomics Center (HBMC), Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
| |
Collapse
|
18
|
Hater F, Nakel T, Groß-Hardt R. Reproductive Multitasking: The Female Gametophyte. ANNUAL REVIEW OF PLANT BIOLOGY 2020; 71:517-546. [PMID: 32442389 DOI: 10.1146/annurev-arplant-081519-035943] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Fertilization of flowering plants requires the organization of complex tasks, many of which become integrated by the female gametophyte (FG). The FG is a few-celled haploid structure that orchestrates division of labor to coordinate successful interaction with the sperm cells and their transport vehicle, the pollen tube. As reproductive outcome is directly coupled to evolutionary success, the underlying mechanisms are under robust molecular control, including integrity check and repair mechanisms. Here, we review progress on understanding the development and function of the FG, starting with the functional megaspore, which represents the haploid founder cell of the FG. We highlight recent achievements that have greatly advanced our understanding of pollen tube attraction strategies and the mechanisms that regulate plant hybridization and gamete fusion. In addition, we discuss novel insights into plant polyploidization strategies that expand current concepts on the evolution of flowering plants.
Collapse
Affiliation(s)
- Friederike Hater
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
| | - Thomas Nakel
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
| | - Rita Groß-Hardt
- Centre for Biomolecular Interactions, University of Bremen, 28359 Bremen, Germany;
| |
Collapse
|
19
|
Liu X, Wu X, Adhikari PB, Zhu S, Kinoshita Y, Berger F, Higashiyama T, Kasahara RD. Establishment of a novel method for the identification of fertilization defective mutants in Arabidopsis thaliana. Biochem Biophys Res Commun 2020; 521:928-932. [PMID: 31711640 DOI: 10.1016/j.bbrc.2019.11.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 11/04/2019] [Indexed: 10/25/2022]
Abstract
Plant reproduction is an extremely important phenomenon, as it is strongly associated with plant genetics and early development. Additionally, foundations of the reproductive system have direct implications on plant breeding and agriculture. Investigation of the functions of male and female gametophytes is critical since their fusion is required for seed formation. Although a large number of mutants have been generated to understand the functions of male and female gametophytes, only a small number of genes required for plant fertilization have been identified to date. This is because the screening method used previously required the dissection of siliques, and fertilization-specific mutants exhibiting semi-fertility (or ∼50% fertility) were difficult to identify. Here, we report a new efficient screening method for the identification of fertilization defective mutants in Arabidopsis thaliana using vanillin staining. This method is based on the pollen tube-dependent ovule enlargement morphology (POEM) phenomenon, which generates a partial seed coat within the ovule without fertilization. Using this method, we successfully identified 23 putative fertilization defective mutants in Arabidopsis.
Collapse
Affiliation(s)
- Xiaoyan Liu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Xiaoyan Wu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Prakash Babu Adhikari
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Shaowei Zhu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Yoshihiro Kinoshita
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan
| | - Frederic Berger
- Gregor Mendel Institute of Molecular Plant Biology GmbH Dr, Bohr-Gasse 3, 1030, Vienna, Austria
| | - Tetsuya Higashiyama
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan; Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8601, Japan
| | - Ryushiro D Kasahara
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China; FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China.
| |
Collapse
|
20
|
Milutinovic M, Lindsey BE, Wijeratne A, Hernandez JM, Grotewold N, Fernández V, Grotewold E, Brkljacic J. Arabidopsis EMSY-like (EML) histone readers are necessary for post-fertilization seed development, but prevent fertilization-independent seed formation. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 285:99-109. [PMID: 31203898 DOI: 10.1016/j.plantsci.2019.04.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/07/2019] [Accepted: 04/09/2019] [Indexed: 06/09/2023]
Abstract
Seed development is a complex regulatory process that includes a transition from gametophytic to sporophytic program. The synchronized development of different seed compartments (seed coat, endosperm and embryo) depends on a balance in parental genome contributions. In the most severe cases, the disruption of the balance leads to seed abortion. This represents one of the main obstacles for the engineering of asexual reproduction through seeds (apomixis), and for generating new interspecies hybrids. The repression of auxin synthesis by the Polycomb Repressive Complex 2 (PRC2) is a major mechanism contributing to sensing genome balance. However, current efforts focusing on decreasing PRC2 or elevating auxin levels have not yet resulted in the production of apomictic seed. Here, we show that EMSY-Like Tudor/Agenet H3K36me3 histone readers EML1 and EML3 are necessary for early stages of seed development to proceed at a normal rate in Arabidopsis. We further demonstrate that both EML1 and EML3 are required to prevent the initiation of seed development in the absence of fertilization. Based on the whole genome expression analysis, we identify auxin transport and signaling genes as the most enriched downstream targets of EML1 and EML3. We hypothesize that EML1 and EML3 function to repress and soften paternal gene expression by fine-tuning auxin responses. Discovery of this pathway may contribute to the engineering of apomixis and interspecies hybrids.
Collapse
Affiliation(s)
- Milica Milutinovic
- Arabidopsis Biological Resource Center, The Ohio State University, Columbus, OH, 43210, USA
| | - Benson E Lindsey
- Arabidopsis Biological Resource Center, The Ohio State University, Columbus, OH, 43210, USA
| | - Asela Wijeratne
- Department of Molecular Genetics, Center for Applied Plant Sciences, The Ohio State University, Columbus, OH, 43210, USA
| | - J Marcela Hernandez
- Department of Molecular Genetics, Center for Applied Plant Sciences, The Ohio State University, Columbus, OH, 43210, USA
| | - Nikolas Grotewold
- Arabidopsis Biological Resource Center, The Ohio State University, Columbus, OH, 43210, USA
| | - Virginia Fernández
- Arabidopsis Biological Resource Center, The Ohio State University, Columbus, OH, 43210, USA
| | - Erich Grotewold
- Department of Molecular Genetics, Center for Applied Plant Sciences, The Ohio State University, Columbus, OH, 43210, USA.
| | - Jelena Brkljacic
- Arabidopsis Biological Resource Center, The Ohio State University, Columbus, OH, 43210, USA.
| |
Collapse
|
21
|
Liu X, Adhikari PB, Kasahara RD. Pollen tube contents from failed fertilization contribute to seed coat initiation in Arabidopsis. F1000Res 2019; 8:348. [PMID: 31031972 PMCID: PMC6468697 DOI: 10.12688/f1000research.18644.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/26/2019] [Indexed: 11/20/2022] Open
Abstract
Plant seeds are essential for human beings, constituting 70% of carbohydrate resources worldwide; examples include rice, wheat, and corn. In angiosperms, fertilization of the egg by a sperm cell is required for seed formation; therefore, fertilization failure results in no seed formation, except in the special case of apomixis. Initially, plants produce many pollen grains inside the anthers; once the pollen grain is deposited onto the top of the pistil, the pollen tube elongates until it reaches the ovule. Generally, only one pollen tube is inserted into the ovule; however, we previously found that if fertilization by the first pollen tube fails, a second pollen tube could rescue fertilization via the so-called fertilization recovery system (FRS). Our previous reports also demonstrated that failed fertilization results in pollen tube-dependent ovule enlargement morphology (POEM), enlarged seeds, and partial seed coat formation if the pollen tube releases the pollen tube contents into the ovule. However, we have not determined whether all the ovules enlarge or produce seed coats if an ovule accepts the pollen tube contents. Therefore, we conducted a partial seed coat formation experiment taking into account both the FRS and POEM phenomena. Notably, the ratios of failed fertilization and the ovules with partial seed coats matched, indicating that all ovules initiate seed coat formation if the fertilization fails but the pollen tube contents enter the ovule. In addition, we confirmed that the agl62 mutant , defective in early endosperm formation, showed seed coat initiation with and without fertilization, indicating that for a normal seed coat initiation, fertilization is not required; however, for the completion of normal seed coat formation, both normal fertilization and endosperm formation are required. Further molecular evidence is required to understand these phenomena because very few factors related to FRS and POEM have been identified.
Collapse
Affiliation(s)
- Xiaoyan Liu
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.,FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Parakash Babu Adhikari
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.,FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| | - Ryushiro D Kasahara
- School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China.,FAFU-UCR Joint Center and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, China
| |
Collapse
|
22
|
Abstract
This review by Figueiredo and Köhler describes the molecular mechanisms driving seed development. They review the role of the hormone auxin for the initial development of the three seed structures and as a trigger of fertilization-independent seed development. The evolution of seeds defines a remarkable landmark in the history of land plants. A developing seed contains three genetically distinct structures: the embryo, the nourishing tissue, and the seed coat. While fertilization is necessary to initiate seed development in most plant species, apomicts have evolved mechanisms allowing seed formation independently of fertilization. Despite their socio–economical relevance, the molecular mechanisms driving seed development have only recently begun to be understood. Here we review the current knowledge on the role of the hormone auxin for the initial development of the three seed structures and as a trigger of fertilization-independent seed development.
Collapse
Affiliation(s)
- Duarte D Figueiredo
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
| | - Claudia Köhler
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
| |
Collapse
|
23
|
Kanaoka MM. Cell-cell communications and molecular mechanisms in plant sexual reproduction. JOURNAL OF PLANT RESEARCH 2018; 131:37-47. [PMID: 29181649 DOI: 10.1007/s10265-017-0997-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 10/29/2017] [Indexed: 06/07/2023]
Abstract
Sexual reproduction is achieved by precise interactions between male and female reproductive organs. In plant fertilization, sperm cells are carried to ovules by pollen tubes. Signals from the pistil are involved in elongation and control of the direction of the pollen tube. Genetic, reverse genetic, and cell biological analyses using model plants have identified various factors related to the regulation of pollen tube growth and guidance. In this review, I summarize the mechanisms and molecules controlling pollen tube growth to the ovule, micropylar guidance, reception of the guidance signal in the pollen tube, rupture of the pollen tube to release sperm cells, and cessation of the tube guidance signal. I also briefly introduce various techniques used to analyze pollen tube guidance in vitro.
Collapse
Affiliation(s)
- Masahiro M Kanaoka
- Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8602, Japan.
| |
Collapse
|
24
|
Fiume E, Coen O, Xu W, Lepiniec L, Magnani E. Developmental patterning of sub-epidermal cells in the outer integument of Arabidopsis seeds. PLoS One 2017; 12:e0188148. [PMID: 29141031 PMCID: PMC5687734 DOI: 10.1371/journal.pone.0188148] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 11/01/2017] [Indexed: 11/18/2022] Open
Abstract
The seed, the reproductive unit of angiosperms, is generally protected by the seed coat. The seed coat is made of one or two integuments, each comprising two epidermal cells layers and, in some cases, extra sub-epidermal cell layers. The thickness of the seed-coat affects several aspects of seed biology such as dormancy, germination and mortality. In Arabidopsis, the inner integument displays one or two sub-epidermal cell layers that originate from periclinal cell divisions of the innermost epidermal cell layer. By contrast, the outer integument was considered to be two-cell layered. Here, we show that sub-epidermal chalazal cells grow in between the epidermal outer integument cell layers to create an incomplete three-cell layered outer integument. We found that the MADS box transcription factor TRANSPARENT TESTA 16 represses growth of the chalaza and formation of sub-epidermal outer integument cells. Finally, we demonstrate that sub-epidermal cells of the outer and inner integument respond differently to the repressive mechanism mediated by FERTILIZATION INDEPENDENT SEED Polycomb group proteins and to fertilization signals. Our data suggest that integument cell origin rather than sub-epidermal cell position underlies different responses to fertilization.
Collapse
Affiliation(s)
- Elisa Fiume
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Versailles, France
| | - Olivier Coen
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Versailles, France
- Ecole Doctorale 567 Sciences du Végétal, University Paris-Sud, University of Paris-Saclay, bat 360, Orsay, France
| | - Wenjia Xu
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Versailles, France
| | - Loïc Lepiniec
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Versailles, France
| | - Enrico Magnani
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Versailles, France
- * E-mail:
| |
Collapse
|
25
|
Qu LJ, Sun MX. Plant reproduction: Recent discoveries from China. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2017; 59:591-593. [PMID: 28805951 DOI: 10.1111/jipb.12576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Affiliation(s)
- Li-Jia Qu
- College of Life Sciences, Peking University, Beijing, China
| | - Meng-Xiang Sun
- College of Life Sciences, Wuhan University, Wuhan, China
| |
Collapse
|
26
|
Zhong S, Zhang J, Qu LJ. The signals to trigger the initiation of ovule enlargement are from the pollen tubes: The direct evidence. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2017; 59:600-603. [PMID: 28815896 DOI: 10.1111/jipb.12577] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 08/14/2017] [Indexed: 06/07/2023]
Abstract
In angiosperms, initiation of ovule enlargement represents the start of seed development, the molecular mechanism of which is not yet elucidated. It was previously reported that pollen tube contents, rather than double fertilization, can trigger ovule enlargement. However, it remains unclear whether the signal(s) to trigger the initiation of ovule enlargement are from the sperm cells or from the pollen tubes. Recently, we identified a mutant drop1- drop2-, which produces pollen tubes with no sperm cells. Taking advantage of this special genetic material, we conducted pollination assays, and found that the ovules pollinated with drop1- drop2- pollen could initiate the enlargement and exhibited significant enlarged sizes at 36 h after pollination in comparison with those unpollinated ovules. However, the sizes of the ovules pollinated with drop1- drop2- pollen are significantly smaller than those of the ovules pollinated with wild-type pollen. These results demonstrate that the pollen tube, rather than the sperm cells, release the signal to trigger the initiation of ovule enlargement, and that double fertilization is required for further enlargement of the seeds.
Collapse
Affiliation(s)
- Sheng Zhong
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, China
| | - Jun Zhang
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, China
| | - Li-Jia Qu
- State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences at College of Life Sciences, Peking University, Beijing 100871, China
- The National Plant Gene Research Center (Beijing), Beijing 100101, China
| |
Collapse
|
27
|
Fiume E, Coen O, Xu W, Lepiniec L, Magnani E. Growth of the Arabidopsis sub-epidermal integument cell layers might require an endosperm signal. PLANT SIGNALING & BEHAVIOR 2017; 12:e1339000. [PMID: 28613109 PMCID: PMC5616150 DOI: 10.1080/15592324.2017.1339000] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The seed, the reproductive unit of angiosperms, is physically protected by the seed coat. The seed coat develops from the ovule integuments after fertilization. The Arabidopsis ovule integuments are made of 5-6 cell layers of epidermal and sub-epidermal origin. The growth of the epidermal integument cell layers responds to an endosperm signal mediated by the AGAMOUS-LIKE 62 MADS box transcription factor with limited embryo contribution. By contrast, the sub-epidermal integument cell layers require the embryo to expand whereas the role of the endosperm is still unclear. Here, we analyzed the development of the sub-epidermal integument cell layers in agl62 mutant seeds, which undergo premature endosperm cellularization and arrest. Our data suggest that embryo and endosperm are both necessary to trigger the expansion of the sub-epidermal integument cell layers.
Collapse
Affiliation(s)
- Elisa Fiume
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, France
| | - Olivier Coen
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, France
- Ecole Doctorale 567 Sciences du Végétal, University Paris-Sud, University of Paris-Saclay, France
| | - Wenjia Xu
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, France
| | - Loïc Lepiniec
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, France
| | - Enrico Magnani
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, France
- CONTACT Enrico Magnani Institut Jean-Pierre Bourgin, INRA Centre de Versailles-Grignon, Route de St-Cyr (RD10), 78026 Versailles, Cedex, France
| |
Collapse
|
28
|
Higashiyama T. Pollen tube navigation can inspire microrobot design. Sci Robot 2017; 2:2/8/eaao1891. [DOI: 10.1126/scirobotics.aao1891] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 07/14/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Tetsuya Higashiyama
- Institute of Transformative Bio-Molecules (WPI-ITbM) and Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601 Aichi, Japan
| |
Collapse
|
29
|
Kasahara RD, Notaguchi M, Honma Y. Discovery of pollen tube-dependent ovule enlargement morphology phenomenon, a new step in plant reproduction. Commun Integr Biol 2017. [PMCID: PMC5595410 DOI: 10.1080/19420889.2017.1338989] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
In animals, when semen is discharged into the uterus, the seminal plasma carries the sperm to the egg. In plants, the function of pollen tube contents (PTC) is analogous to that of the seminal plasma in animals, i.e., carrying sperm cells to the ovules for fertilization. Because the function of the seminal plasma is essential for fertilization in animals, we propose that the function of PTC must be important for plant fertilization. To understand the function of PTC, we examined the transcriptional variation after the release of PTC into the embryo sac. The phenotypic analysis revealed that ovules were enlarged without fertilization when the PTC was released into the ovule, entirely consistent with the transcriptome analysis. We identified a new plant phenomenon, pollen tube-dependent ovule enlargement morphology (POEM) phenomenon that occurs only when the ovule accepts PTC, irrespective of fertilization. POEM is a new phase between the pollen tube guidance and fertilization phases as a reproductive step. Here we established the in vitro POEM assay, which effectively measures POEM activity. Using this assay, we identified that a simple dose of plant hormone(s) cannot induce POEM. We also showed that this assay could be a powerful tool for identifying POEM factor(s).
Collapse
Affiliation(s)
- Ryushiro D. Kasahara
- PRESTO Kasahara Sakigake Project, Japan Science and Technology Agency (JST), Furo, Chikusa, Nagoya, Aichi, Japan
- Institute of transformative bio-molecules, Nagoya University, Furo, Chikusa, Nagoya, Aichi, Japan
| | - Michitaka Notaguchi
- Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya, Aichi, Japan
- PRESTO, JST, Furo, Chikusa, Nagoya, Aichi, Japan
| | - Yujiro Honma
- PRESTO Kasahara Sakigake Project, Japan Science and Technology Agency (JST), Furo, Chikusa, Nagoya, Aichi, Japan
- Institute of transformative bio-molecules, Nagoya University, Furo, Chikusa, Nagoya, Aichi, Japan
| |
Collapse
|
30
|
Coen O, Fiume E, Xu W, De Vos D, Lu J, Pechoux C, Lepiniec L, Magnani E. Developmental patterning of the sub-epidermal integument cell layer in Arabidopsis seeds. Development 2017; 144:1490-1497. [PMID: 28348169 PMCID: PMC5399669 DOI: 10.1242/dev.146274] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 03/06/2017] [Indexed: 12/14/2022]
Abstract
Angiosperm seed development is a paradigm of tissue cross-talk. Proper seed formation requires spatial and temporal coordination of the fertilization products – embryo and endosperm – and the surrounding seed coat maternal tissue. In early Arabidopsis seed development, all seed integuments were thought to respond homogenously to endosperm growth. Here, we show that the sub-epidermal integument cell layer has a unique developmental program. We characterized the cell patterning of the sub-epidermal integument cell layer, which initiates a previously uncharacterized extra cell layer, and identified TRANSPARENT TESTA 16 and SEEDSTICK MADS box transcription factors as master regulators of its polar development and cell architecture. Our data indicate that the differentiation of the sub-epidermal integument cell layer is insensitive to endosperm growth alone and to the repressive mechanism established by FERTILIZATION INDEPENDENT ENDOSPERM and MULTICOPY SUPPRESSOR OF IRA1 Polycomb group proteins. This work demonstrates the different responses of epidermal and sub-epidermal integument cell layers to fertilization. Summary: The sub-epidermal integument cell layer of the Arabidopsis seed coat is insensitive to endosperm growth alone and displays a unique response to fertilization.
Collapse
Affiliation(s)
- Olivier Coen
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), Versailles Cedex 78026, France.,Ecole Doctorale 567 Sciences du Végétal, University Paris-Sud, University of Paris-Saclay, bat 360, Orsay Cedex 91405, France
| | - Elisa Fiume
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), Versailles Cedex 78026, France
| | - Wenjia Xu
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), Versailles Cedex 78026, France
| | - Delphine De Vos
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), Versailles Cedex 78026, France
| | - Jing Lu
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), Versailles Cedex 78026, France.,Ecole Doctorale 567 Sciences du Végétal, University Paris-Sud, University of Paris-Saclay, bat 360, Orsay Cedex 91405, France
| | - Christine Pechoux
- INRA, Génétique Animale et Biologie Intégrative, Domaine de Vilvert, Jouy-en-Josas Cedex 78352, France
| | - Loïc Lepiniec
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), Versailles Cedex 78026, France
| | - Enrico Magnani
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, University of Paris-Saclay, Route de St-Cyr (RD10), Versailles Cedex 78026, France
| |
Collapse
|