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Yan H, Mendieta JP, Zhang X, Marand AP, Liang Y, Luo Z, Minow MAA, Jang H, Li X, Roule T, Wagner D, Tu X, Wang Y, Jiang D, Zhong S, Huang L, Wessler SR, Schmitz RJ. Evolution of plant cell-type-specific cis-regulatory elements. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.08.574753. [PMID: 38260561 PMCID: PMC10802394 DOI: 10.1101/2024.01.08.574753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Cis-regulatory elements (CREs) are critical in regulating gene expression, and yet understanding of CRE evolution remains challenging. Here, we constructed a comprehensive single-cell atlas of chromatin accessibility in Oryza sativa, integrating data from 103,911 nuclei representing 126 discrete cell states across nine distinct organs. We used comparative genomics to compare cell-type resolved chromatin accessibility between O. sativa and 57,552 nuclei from four additional grass species (Zea mays, Sorghum bicolor, Panicum miliaceum, and Urochloa fusca). Accessible chromatin regions (ACRs) had different levels of conservation depending on the degree of cell-type specificity. We found a complex relationship between ACRs with conserved noncoding sequences, cell-type specificity, conservation, and tissue-specific switching. Additionally, we found that epidermal ACRs were less conserved compared to other cell types, potentially indicating that more rapid regulatory evolution has occurred in the L1-derived epidermal layer of these species. Finally, we identified and characterized a conserved subset of ACRs that overlapped the repressive histone modification H3K27me3, implicating them as potentially silencer-like CREs maintained by evolution. Collectively, this comparative genomics approach highlights the dynamics of plant cell-type-specific CRE evolution.
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2
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Tonosaki K, Susaki D, Morinaka H, Ono A, Nagata H, Furuumi H, Nonomura KI, Sato Y, Sugimoto K, Comai L, Hatakeyama K, Kawakatsu T, Kinoshita T. Multilayered epigenetic control of persistent and stage-specific imprinted genes in rice endosperm. NATURE PLANTS 2024; 10:1231-1245. [PMID: 39080502 DOI: 10.1038/s41477-024-01754-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 07/01/2024] [Indexed: 08/22/2024]
Abstract
In angiosperms, epigenetic profiles for genomic imprinting are established before fertilization. However, the causal relationships between epigenetic modifications and imprinted expression are not fully understood. In this study, we classified 'persistent' and 'stage-specific' imprinted genes on the basis of time-course transcriptome analysis in rice (Oryza sativa) endosperm and compared them to epigenetic modifications at a single time point. While the levels of epigenetic modifications are relatively low in stage-specific imprinted genes, they are considerably higher in persistent imprinted genes. Overall trends revealed that the maternal alleles of maternally expressed imprinted genes are activated by DNA demethylation, while the maternal alleles of paternally expressed imprinted genes with gene body methylation (gbM) are silenced by DNA demethylation and H3K27me3 deposition, and these regions are associated with an enriched motif related to Tc/Mar-Stowaway. Our findings provide insight into the stability of genomic imprinting and the potential variations associated with endosperm development, different cell types and parental genotypes.
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Grants
- 20K15504 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 22K15145 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 23H04749 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 23H04756 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 23K23585 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 22H05175 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 21H02170 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- 22H02320 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
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Affiliation(s)
- Kaoru Tonosaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Kanagawa, Japan.
- Faculty of Agriculture, Iwate University, Morioka, Iwate, Japan.
| | - Daichi Susaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Kanagawa, Japan
| | - Hatsune Morinaka
- RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan
| | - Akemi Ono
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Kanagawa, Japan
| | - Hiroki Nagata
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Kanagawa, Japan
| | - Hiroyasu Furuumi
- Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Ken-Ichi Nonomura
- Plant Cytogenetics, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Yutaka Sato
- Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Keiko Sugimoto
- RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan
| | - Luca Comai
- Department of Plant Biology and Genome Center, University of California, Davis, CA, USA
| | | | - Taiji Kawakatsu
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Kanagawa, Japan.
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3
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Zhang J, Zhang Z, Zhang R, Yang C, Zhang X, Chang S, Chen Q, Rossi V, Zhao L, Xiao J, Xin M, Du J, Guo W, Hu Z, Liu J, Peng H, Ni Z, Sun Q, Yao Y. Type I MADS-box transcription factor TaMADS-GS regulates grain size by stabilizing cytokinin signalling during endosperm cellularization in wheat. PLANT BIOTECHNOLOGY JOURNAL 2024; 22:200-215. [PMID: 37752705 PMCID: PMC10754016 DOI: 10.1111/pbi.14180] [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: 05/03/2023] [Revised: 09/01/2023] [Accepted: 09/09/2023] [Indexed: 09/28/2023]
Abstract
Grain size is one of the important traits in wheat breeding programs aimed at improving yield, and cytokinins, mainly involved in cell division, have a positive impact on grain size. Here, we identified a novel wheat gene TaMADS-GS encoding type I MADS-box transcription factor, which regulates the cytokinins signalling pathway during early stages of grain development to modulate grain size and weight in wheat. TaMADS-GS is exclusively expressed in grains at early stage of seed development and its knockout leads to delayed endosperm cellularization, smaller grain size and lower grain weight. TaMADS-GS protein interacts with the Polycomb Repressive Complex 2 (PRC2) and leads to repression of genes encoding cytokinin oxidase/dehydrogenases (CKXs) stimulating cytokinins inactivation by mediating accumulation of the histone H3 trimethylation at lysine 27 (H3K27me3). Through the screening of a large wheat germplasm collection, an elite allele of the TaMADS-GS exhibits higher ability to repress expression of genes inactivating cytokinins and a positive correlation with grain size and weight, thus representing a novel marker for breeding programs in wheat. Overall, these findings support the relevance of TaMADS-GS as a key regulator of wheat grain size and weight.
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Affiliation(s)
- Jianing Zhang
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Zhaoheng Zhang
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Ruijie Zhang
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Changfeng Yang
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Xiaobang Zhang
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Siyuan Chang
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Qian Chen
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Vincenzo Rossi
- Council for Agricultural Research and EconomicsResearch Centre for Cereal and Industrial CropsBergamoItaly
| | - Long Zhao
- Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
| | - Jun Xiao
- Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijingChina
| | - Mingming Xin
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Jinkun Du
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Weilong Guo
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Zhaorong Hu
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Jie Liu
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Huiru Peng
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Zhongfu Ni
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Qixin Sun
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
| | - Yingyin Yao
- Frontiers Science Center for Molecular Design Breeding, Key Laboratory of Crop Heterosis and Utilization (MOE), and Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijingChina
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Tonosaki K, Kinoshita T. Polycomb repression of the asexual embryo. NATURE PLANTS 2023; 9:1783-1784. [PMID: 37814023 DOI: 10.1038/s41477-023-01537-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Affiliation(s)
- Kaoru Tonosaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan.
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan.
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5
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Kan Y, Mu XR, Gao J, Lin HX, Lin Y. The molecular basis of heat stress responses in plants. MOLECULAR PLANT 2023; 16:1612-1634. [PMID: 37740489 DOI: 10.1016/j.molp.2023.09.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 08/30/2023] [Accepted: 09/19/2023] [Indexed: 09/24/2023]
Abstract
Global warming impacts crop production and threatens food security. Elevated temperatures are sensed by different cell components. Temperature increases are classified as either mild warm temperatures or excessively hot temperatures, which are perceived by distinct signaling pathways in plants. Warm temperatures induce thermomorphogenesis, while high-temperature stress triggers heat acclimation and has destructive effects on plant growth and development. In this review, we systematically summarize the heat-responsive genetic networks in Arabidopsis and crop plants based on recent studies. In addition, we highlight the strategies used to improve grain yield under heat stress from a source-sink perspective. We also discuss the remaining issues regarding the characteristics of thermosensors and the urgency required to explore the basis of acclimation under multifactorial stress combination.
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Affiliation(s)
- Yi Kan
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Xiao-Rui Mu
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Jin Gao
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Hong-Xuan Lin
- National Key Laboratory of Plant Molecular Genetics, CAS Centre for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; University of the Chinese Academy of Sciences, Beijing 100049, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China.
| | - Youshun Lin
- Joint Center for Single Cell Biology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
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6
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Li JY, Yang C, Xu J, Lu HP, Liu JX. The hot science in rice research: How rice plants cope with heat stress. PLANT, CELL & ENVIRONMENT 2023; 46:1087-1103. [PMID: 36478590 DOI: 10.1111/pce.14509] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 11/13/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
Global climate change has great impacts on plant growth and development, reducing crop productivity worldwide. Rice (Oryza sativa L.), one of the world's most important food crops, is susceptible to high-temperature stress from seedling stage to reproductive stage. In this review, we summarize recent advances in understanding the molecular mechanisms underlying heat stress responses in rice, including heat sensing and signalling, transcriptional regulation, transcript processing, protein translation, and post-translational regulation. We also highlight the irreversible effects of high temperature on reproduction and grain quality in rice. Finally, we discuss challenges and opportunities for future research on heat stress responses in rice.
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Affiliation(s)
- Jin-Yu Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Chuang Yang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Jiming Xu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Hai-Ping Lu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Jian-Xiang Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, China
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7
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Singh KBM, Thakur JK. Endosperm ontogeny through the lens of epigenetics. MOLECULAR PLANT 2023; 16:295-297. [PMID: 36258669 DOI: 10.1016/j.molp.2022.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/15/2022] [Accepted: 10/16/2022] [Indexed: 06/16/2023]
Affiliation(s)
- Kajol B M Singh
- National Institute of Plant Genome Research, New Delhi 110067, India
| | - Jitendra K Thakur
- National Institute of Plant Genome Research, New Delhi 110067, India; International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India.
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8
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Cheng K, Lei C, Zhang S, Zheng Q, Wei C, Huang W, Xing M, Zhang J, Zhang X, Zhang X. Genome-wide identification and characterization of polycomb repressive complex 2 core components in upland cotton (Gossypium hirsutum L.). BMC PLANT BIOLOGY 2023; 23:66. [PMID: 36721081 PMCID: PMC9890721 DOI: 10.1186/s12870-023-04075-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND The evolutionarily conserved Polycomb Repressive Complex 2 (PRC2) plays a vital role in epigenetic gene repression by depositing tri-methylation on lysine residue K27 of histone H3 (H3K27me3) at the target loci, thus participating in diverse biological processes. However, few reports about PRC2 are available in plant species with large and complicated genomes, like cotton. RESULTS Here, we performed a genome-wide identification and comprehensive analysis of cotton PRC2 core components, especially in upland cotton (Gossypium hirsutum). Firstly, a total of 8 and 16 PRC2 core components were identified in diploid and tetraploid cotton species, respectively. These components were classified into four groups, E(z), Su(z)12, ESC and p55, and the members in the same group displayed good collinearity, similar gene structure and domain organization. Next, we cloned G. hirsutum PRC2 (GhPRC2) core components, and found that most of GhPRC2 proteins were localized in the nucleus, and interacted with each other to form multi-subunit complexes. Moreover, we analyzed the expression profile of GhPRC2 genes. The transcriptome data and quantitative real-time PCR (qRT-PCR) assays indicated that GhPRC2 genes were ubiquitously but differentially expressed in various tissues, with high expression levels in reproductive organs like petals, stamens and pistils. And the expressions of several GhPRC2 genes, especially E(z) group genes, were responsive to various abiotic and biotic stresses, including drought, salinity, extreme temperature, and Verticillium dahliae (Vd) infection. CONCLUSION We identified PRC2 core components in upland cotton, and systematically investigated their classifications, phylogenetic and synteny relationships, gene structures, domain organizations, subcellular localizations, protein interactions, tissue-specific and stresses-responsive expression patterns. Our results will provide insights into the evolution and composition of cotton PRC2, and lay the foundation for further investigation of their biological functions and regulatory mechanisms.
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Affiliation(s)
- Kai Cheng
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Cangbao Lei
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Siyuan Zhang
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Qiao Zheng
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Chunyan Wei
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Weiyi Huang
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Minghui Xing
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Junli Zhang
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Xiangyu Zhang
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China
| | - Xiao Zhang
- State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, 475001, Kaifeng, China.
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Wu D, Wei Y, Zhao X, Li B, Zhang H, Xu G, Lv J, Zhang D, Zhang X, Ni M. Ancestral function but divergent epigenetic regulation of HAIKU2 reveals routes of seed developmental evolution. MOLECULAR PLANT 2022; 15:1575-1589. [PMID: 36071671 DOI: 10.1016/j.molp.2022.09.002] [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: 05/13/2022] [Revised: 07/19/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
Evolution is driven by various mechanisms. A directional increase in the embryo to endosperm ratio is an evolutionary trend within the angiosperms. The endosperm constitutes a major portion of the seed volume in Poales and some dicots. However, in other dicots such as Arabidopsis and soybean, the endosperm proliferates early, followed by embryo growth to replace the endosperm. The Arabidopsis leucine-rich repeat receptor protein kinase AtHAIKU2 (AtIKU2) is a key regulator of early endosperm proliferation. In this study, we found that IKU2s from Brachypodium, rice, and soybean can complement the abnormal seed developmental phenotype of Atiku2, while AtIKU2 also rescues the defective endosperm proliferation in the Brachypodium BdIKU2 knockout mutant seeds. AtIKU2 and soybean GmIKU2 are actively expressed a few days after fertilization. Thereafter, expression of AtIKU2 is suppressed by the FIS-PRC2 complex-mediated H3K27me3. The soybean GmIKU2 locus is also enriched with H3K27me3 marks. The histone methyltransferase AtMEA is unique to Brassicaceae, but one GmSWN in soybean plays a similar role in seed development as AtMEA. By contrast, the BdIKU2 and rice OsIKU2 loci are continuously expressed and are devoid of H3K27me3 marks. Taken together, these results suggest that IKU2 genes retain an ancestral function, but the duration of their expression that is controlled by PRC2-mediated epigenetic silencing contributes to silenced or persistent endosperm proliferation in different species. Our study reveals an epigenetic mechanism that drives the development of vastly different seed ontogenies.
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Affiliation(s)
- Di Wu
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
| | - Yiming Wei
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
| | - Xiangyu Zhao
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
| | - Boka Li
- State Key Laboratory of Systematic and Evolutionary Botany, CAS Center for Excellence in Molecular Plant Sciences, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huankai Zhang
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
| | - Gang Xu
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
| | - Juntong Lv
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
| | - Dajian Zhang
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China
| | - Xiansheng Zhang
- National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian 271018, China.
| | - Min Ni
- Department of Plant and Microbial Biology, University of Minnesota at Twin Cities, Saint Paul, MN 55108, USA.
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10
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Tonosaki K, Fujimoto R, Dennis ES, Raboy V, Osabe K. Will epigenetics be a key player in crop breeding? FRONTIERS IN PLANT SCIENCE 2022; 13:958350. [PMID: 36247549 PMCID: PMC9562705 DOI: 10.3389/fpls.2022.958350] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
If food and feed production are to keep up with world demand in the face of climate change, continued progress in understanding and utilizing both genetic and epigenetic sources of crop variation is necessary. Progress in plant breeding has traditionally been thought to be due to selection for spontaneous DNA sequence mutations that impart desirable phenotypes. These spontaneous mutations can expand phenotypic diversity, from which breeders can select agronomically useful traits. However, it has become clear that phenotypic diversity can be generated even when the genome sequence is unaltered. Epigenetic gene regulation is a mechanism by which genome expression is regulated without altering the DNA sequence. With the development of high throughput DNA sequencers, it has become possible to analyze the epigenetic state of the whole genome, which is termed the epigenome. These techniques enable us to identify spontaneous epigenetic mutations (epimutations) with high throughput and identify the epimutations that lead to increased phenotypic diversity. These epimutations can create new phenotypes and the causative epimutations can be inherited over generations. There is evidence of selected agronomic traits being conditioned by heritable epimutations, and breeders may have historically selected for epiallele-conditioned agronomic traits. These results imply that not only DNA sequence diversity, but the diversity of epigenetic states can contribute to increased phenotypic diversity. However, since the modes of induction and transmission of epialleles and their stability differ from that of genetic alleles, the importance of inheritance as classically defined also differs. For example, there may be a difference between the types of epigenetic inheritance important to crop breeding and crop production. The former may depend more on longer-term inheritance whereas the latter may simply take advantage of shorter-term phenomena. With the advances in our understanding of epigenetics, epigenetics may bring new perspectives for crop improvement, such as the use of epigenetic variation or epigenome editing in breeding. In this review, we will introduce the role of epigenetic variation in plant breeding, largely focusing on DNA methylation, and conclude by asking to what extent new knowledge of epigenetics in crop breeding has led to documented cases of its successful use.
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Affiliation(s)
- Kaoru Tonosaki
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Japan
| | - Ryo Fujimoto
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
| | - Elizabeth S. Dennis
- Commonwealth Scientific and Industrial Research Organisation (CSIRO) Agriculture and Food, Canberra, ACT, Australia
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Victor Raboy
- Independent Researcher Portland, Portland, OR, United States
| | - Kenji Osabe
- Institute of Scientific and Industrial Research (SANKEN), Osaka University, Osaka, Japan
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11
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Vadde BVL. PACP recruits PRC2 to TALE targets. THE PLANT CELL 2022; 34:2821-2822. [PMID: 35666578 PMCID: PMC9338791 DOI: 10.1093/plcell/koac159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 05/18/2022] [Indexed: 05/28/2023]
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12
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Liu J, Wu MW, Liu CM. Cereal Endosperms: Development and Storage Product Accumulation. ANNUAL REVIEW OF PLANT BIOLOGY 2022; 73:255-291. [PMID: 35226815 DOI: 10.1146/annurev-arplant-070221-024405] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The persistent triploid endosperms of cereal crops are the most important source of human food and animal feed. The development of cereal endosperms progresses through coenocytic nuclear division, cellularization, aleurone and starchy endosperm differentiation, and storage product accumulation. In the past few decades, the cell biological processes involved in endosperm formation in most cereals have been described. Molecular genetic studies performed in recent years led to the identification of the genes underlying endosperm differentiation, regulatory network governing storage product accumulation, and epigenetic mechanism underlying imprinted gene expression. In this article, we outline recent progress in this area and propose hypothetical models to illustrate machineries that control aleurone and starchy endosperm differentiation, sugar loading, and storage product accumulations. A future challenge in this area is to decipher the molecular mechanisms underlying coenocytic nuclear division, endosperm cellularization, and programmed cell death.
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Affiliation(s)
- Jinxin Liu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China;
| | - Ming-Wei Wu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China;
| | - Chun-Ming Liu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China;
- Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
- School of Advanced Agricultural Sciences, Peking University, Beijing, China
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13
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Matilla AJ. Exploring Breakthroughs in Three Traits Belonging to Seed Life. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11040490. [PMID: 35214823 PMCID: PMC8875957 DOI: 10.3390/plants11040490] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/02/2022] [Accepted: 02/09/2022] [Indexed: 05/06/2023]
Abstract
Based on prior knowledge and with the support of new methodology, solid progress in the understanding of seed life has taken place over the few last years. This update reflects recent advances in three key traits of seed life (i.e., preharvest sprouting, genomic imprinting, and stored-mRNA). The first breakthrough refers to cloning of the mitogen-activated protein kinase-kinase 3 (MKK3) gene in barley and wheat. MKK3, in cooperation with ABA signaling, controls seed dormancy. This advance has been determinant in producing improved varieties that are resistant to preharvest sprouting. The second advance concerns to uniparental gene expression (i.e., imprinting). Genomic imprinting primarily occurs in the endosperm. Although great advances have taken place in the last decade, there is still a long way to go to complete the puzzle regarding the role of genomic imprinting in seed development. This trait is probably one of the most important epigenetic facets of developing endosperm. An example of imprinting regulation is polycomb repressive complex 2 (PRC2). The mechanism of PRC2 recruitment to target endosperm with specific genes is, at present, robustly studied. Further progress in the knowledge of recruitment of PRC2 epigenetic machinery is considered in this review. The third breakthrough referred to in this update involves stored mRNA. The role of the population of this mRNA in germination is far from known. Its relations to seed aging, processing bodies (P bodies), and RNA binding proteins (RBPs), and how the stored mRNA is targeted to monosomes, are aspects considered here. Perhaps this third trait is the one that will require greater experimental dedication in the future. In order to make progress, herein are included some questions that are needed to be answered.
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Affiliation(s)
- Angel J Matilla
- Departamento de Biología Funcional (Área Fisiología Vegetal), Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
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14
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Vijayanathan M, Trejo-Arellano MG, Mozgová I. Polycomb Repressive Complex 2 in Eukaryotes-An Evolutionary Perspective. EPIGENOMES 2022; 6:3. [PMID: 35076495 PMCID: PMC8788455 DOI: 10.3390/epigenomes6010003] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/12/2022] [Accepted: 01/12/2022] [Indexed: 12/23/2022] Open
Abstract
Polycomb repressive complex 2 (PRC2) represents a group of evolutionarily conserved multi-subunit complexes that repress gene transcription by introducing trimethylation of lysine 27 on histone 3 (H3K27me3). PRC2 activity is of key importance for cell identity specification and developmental phase transitions in animals and plants. The composition, biochemistry, and developmental function of PRC2 in animal and flowering plant model species are relatively well described. Recent evidence demonstrates the presence of PRC2 complexes in various eukaryotic supergroups, suggesting conservation of the complex and its function. Here, we provide an overview of the current understanding of PRC2-mediated repression in different representatives of eukaryotic supergroups with a focus on the green lineage. By comparison of PRC2 in different eukaryotes, we highlight the possible common and diverged features suggesting evolutionary implications and outline emerging questions and directions for future research of polycomb repression and its evolution.
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Affiliation(s)
- Mallika Vijayanathan
- Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, 370 05 Ceske Budejovice, Czech Republic; (M.V.); (M.G.T.-A.)
| | - María Guadalupe Trejo-Arellano
- Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, 370 05 Ceske Budejovice, Czech Republic; (M.V.); (M.G.T.-A.)
| | - Iva Mozgová
- Biology Centre, Institute of Plant Molecular Biology, Czech Academy of Sciences, 370 05 Ceske Budejovice, Czech Republic; (M.V.); (M.G.T.-A.)
- Faculty of Science, University of South Bohemia, 370 05 Ceske Budejovice, Czech Republic
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15
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Zhang H, Xu H, Jiang Y, Zhang H, Wang S, Wang F, Zhu Y. Genetic Control and High Temperature Effects on Starch Biosynthesis and Grain Quality in Rice. FRONTIERS IN PLANT SCIENCE 2021; 12:757997. [PMID: 34975940 PMCID: PMC8718882 DOI: 10.3389/fpls.2021.757997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 11/23/2021] [Indexed: 05/29/2023]
Abstract
Grain quality is one of the key targets to be improved for rice breeders and covers cooking, eating, nutritional, appearance, milling, and sensory properties. Cooking and eating quality are mostly of concern to consumers and mainly determined by starch structure and composition. Although many starch synthesis enzymes have been identified and starch synthesis system has been established for a long time, novel functions of some starch synthesis genes have continually been found, and many important regulatory factors for seed development and grain quality control have recently been identified. Here, we summarize the progress in this field as comprehensively as possible and hopefully reveal some underlying molecular mechanisms controlling eating quality in rice. The regulatory network of amylose content (AC) determination is emphasized, as AC is the most important index for rice eating quality (REQ). Moreover, the regulatory mechanism of REQ, especially AC influenced by high temperature which is concerned as a most harmful environmental factor during grain filling is highlighted in this review.
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Affiliation(s)
- Hua Zhang
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, China
| | - Heng Xu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, China
| | - Yingying Jiang
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, China
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Heng Zhang
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, China
| | - Shiyu Wang
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, China
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, China
| | - Fulin Wang
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, China
| | - Ying Zhu
- State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Science, Hangzhou, China
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16
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Tonosaki K, Ono A, Kunisada M, Nishino M, Nagata H, Sakamoto S, Kijima ST, Furuumi H, Nonomura KI, Sato Y, Ohme-Takagi M, Endo M, Comai L, Hatakeyama K, Kawakatsu T, Kinoshita T. Mutation of the imprinted gene OsEMF2a induces autonomous endosperm development and delayed cellularization in rice. THE PLANT CELL 2021; 33:85-103. [PMID: 33751094 PMCID: PMC8136911 DOI: 10.1093/plcell/koaa006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 10/29/2020] [Indexed: 05/22/2023]
Abstract
In angiosperms, endosperm development comprises a series of developmental transitions controlled by genetic and epigenetic mechanisms that are initiated after double fertilization. Polycomb repressive complex 2 (PRC2) is a key component of these mechanisms that mediate histone H3 lysine 27 trimethylation (H3K27me3); the action of PRC2 is well described in Arabidopsis thaliana but remains uncertain in cereals. In this study, we demonstrate that mutation of the rice (Oryza sativa) gene EMBRYONIC FLOWER2a (OsEMF2a), encoding a zinc-finger containing component of PRC2, causes an autonomous endosperm phenotype involving proliferation of the central cell nuclei with separate cytoplasmic domains, even in the absence of fertilization. Detailed cytological and transcriptomic analyses revealed that the autonomous endosperm can produce storage compounds, starch granules, and protein bodies specific to the endosperm. These events have not been reported in Arabidopsis. After fertilization, we observed an abnormally delayed developmental transition in the endosperm. Transcriptome and H3K27me3 ChIP-seq analyses using endosperm from the emf2a mutant identified downstream targets of PRC2. These included >100 transcription factor genes such as type-I MADS-box genes, which are likely required for endosperm development. Our results demonstrate that OsEMF2a-containing PRC2 controls endosperm developmental programs before and after fertilization.
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Affiliation(s)
- Kaoru Tonosaki
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka, Totsuka, Yokohama, Kanagawa 244-0813, Japan
- Department of Plant Biology and Genome Center, University of California, Davis, CA 95616, USA
- Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka, Iwate 020-8550, Japan
- Author for correspondence: (T.Ki.), (K.T.)
| | - Akemi Ono
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka, Totsuka, Yokohama, Kanagawa 244-0813, Japan
| | - Megumi Kunisada
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka, Totsuka, Yokohama, Kanagawa 244-0813, Japan
| | - Megumi Nishino
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka, Totsuka, Yokohama, Kanagawa 244-0813, Japan
| | - Hiroki Nagata
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka, Totsuka, Yokohama, Kanagawa 244-0813, Japan
| | - Shingo Sakamoto
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan
| | - Saku T Kijima
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan
| | - Hiroyasu Furuumi
- Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Ken-Ichi Nonomura
- Plant Cytogenetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Yutaka Sato
- Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Masaru Ohme-Takagi
- Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
| | - Masaki Endo
- Division of Applied Genetics, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8602, Japan
| | - Luca Comai
- Department of Plant Biology and Genome Center, University of California, Davis, CA 95616, USA
| | - Katsunori Hatakeyama
- Faculty of Agriculture, Iwate University, 3-18-8 Ueda, Morioka, Iwate 020-8550, Japan
| | - Taiji Kawakatsu
- Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8602, Japan
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka, Totsuka, Yokohama, Kanagawa 244-0813, Japan
- Author for correspondence: (T.Ki.), (K.T.)
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17
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Cheng X, Pan M, E Z, Zhou Y, Niu B, Chen C. The maternally expressed polycomb group gene OsEMF2a is essential for endosperm cellularization and imprinting in rice. PLANT COMMUNICATIONS 2021; 2:100092. [PMID: 33511344 DOI: 10.1016/j.xplc.2020.10009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 06/17/2020] [Accepted: 06/22/2020] [Indexed: 05/22/2023]
Abstract
Cellularization is a key event in endosperm development. Polycomb group (PcG) genes, such as Fertilization-Independent Seed 2 (FIS2), are vital for the syncytium-to-cellularization transition in Arabidopsis plants. In this study, we found that OsEMF2a, a rice homolog of the Arabidopsis PcG gene Embryonic Flower2 (EMF2), plays a role similar to that of FIS2 in regard to seed development, although there is limited sequence similarity between the genes. Delayed cellularization was observed in osemf2a, associated with an unusual activation of type I MADS-box genes. The cell cycle was persistently activated in osemf2a caryopses, which was likely caused by cytokinin overproduction. However, the overaccumulation of auxin was not found to be associated with the delayed cellularization. As OsEMF2a is a maternally expressed gene in the endosperm, a paternally inherited functional allele was unable to recover the maternal defects of OsEMF2a. Many imprinted rice genes were deregulated in the defective hybrid seeds of osemf2a (♀)/9311 (♂) (m9). The paternal expression bias of some paternally expressed genes was disrupted in m9 due to either the activation of maternal alleles or the repression of paternal alleles. These findings suggest that OsEMF2a-PRC2-mediated H3K27me3 is necessary for endosperm cellularization and genomic imprinting in rice.
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Affiliation(s)
- Xiaojun Cheng
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Meiyao Pan
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Zhiguo E
- Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Yong Zhou
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Baixiao Niu
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Chen Chen
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
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18
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Cheng X, Pan M, E Z, Zhou Y, Niu B, Chen C. The maternally expressed polycomb group gene OsEMF2a is essential for endosperm cellularization and imprinting in rice. PLANT COMMUNICATIONS 2021; 2:100092. [PMID: 33511344 PMCID: PMC7816080 DOI: 10.1016/j.xplc.2020.100092] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 06/17/2020] [Accepted: 06/22/2020] [Indexed: 05/18/2023]
Abstract
Cellularization is a key event in endosperm development. Polycomb group (PcG) genes, such as Fertilization-Independent Seed 2 (FIS2), are vital for the syncytium-to-cellularization transition in Arabidopsis plants. In this study, we found that OsEMF2a, a rice homolog of the Arabidopsis PcG gene Embryonic Flower2 (EMF2), plays a role similar to that of FIS2 in regard to seed development, although there is limited sequence similarity between the genes. Delayed cellularization was observed in osemf2a, associated with an unusual activation of type I MADS-box genes. The cell cycle was persistently activated in osemf2a caryopses, which was likely caused by cytokinin overproduction. However, the overaccumulation of auxin was not found to be associated with the delayed cellularization. As OsEMF2a is a maternally expressed gene in the endosperm, a paternally inherited functional allele was unable to recover the maternal defects of OsEMF2a. Many imprinted rice genes were deregulated in the defective hybrid seeds of osemf2a (♀)/9311 (♂) (m9). The paternal expression bias of some paternally expressed genes was disrupted in m9 due to either the activation of maternal alleles or the repression of paternal alleles. These findings suggest that OsEMF2a-PRC2-mediated H3K27me3 is necessary for endosperm cellularization and genomic imprinting in rice.
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Affiliation(s)
- Xiaojun Cheng
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Meiyao Pan
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Zhiguo E
- Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Yong Zhou
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Baixiao Niu
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
| | - Chen Chen
- Jiangsu Key Laboratory of Crop Genetics and Physiology, Key Laboratory of Plant Functional Genomics of the Ministry of Education, Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou, China
- Corresponding author
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19
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Strejčková B, Čegan R, Pecinka A, Milec Z, Šafář J. Identification of polycomb repressive complex 1 and 2 core components in hexaploid bread wheat. BMC PLANT BIOLOGY 2020; 20:175. [PMID: 33050875 PMCID: PMC7557041 DOI: 10.1186/s12870-020-02384-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/02/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Polycomb repressive complexes 1 and 2 play important roles in epigenetic gene regulation by posttranslationally modifying specific histone residues. Polycomb repressive complex 2 is responsible for the trimethylation of lysine 27 on histone H3; Polycomb repressive complex 1 catalyzes the monoubiquitination of histone H2A at lysine 119. Both complexes have been thoroughly studied in Arabidopsis, but the evolution of polycomb group gene families in monocots, particularly those with complex allopolyploid origins, is unknown. RESULTS Here, we present the in silico identification of the Polycomb repressive complex 1 and 2 (PRC2, PRC1) subunits in allohexaploid bread wheat, the reconstruction of their evolutionary history and a transcriptional analysis over a series of 33 developmental stages. We identified four main subunits of PRC2 [E(z), Su(z), FIE and MSI] and three main subunits of PRC1 (Pc, Psc and Sce) and determined their chromosomal locations. We found that most of the genes coding for subunit proteins are present as paralogs in bread wheat. Using bread wheat RNA-seq data from different tissues and developmental stages throughout plant ontogenesis revealed variable transcriptional activity for individual paralogs. Phylogenetic analysis showed a high level of protein conservation among temperate cereals. CONCLUSIONS The identification and chromosomal location of the Polycomb repressive complex 1 and 2 core components in bread wheat may enable a deeper understanding of developmental processes, including vernalization, in commonly grown winter wheat.
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Affiliation(s)
- Beáta Strejčková
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 31, 77900, Olomouc, Czech Republic
| | - Radim Čegan
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 31, 77900, Olomouc, Czech Republic
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, 61200, Brno, Czech Republic
| | - Ales Pecinka
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 31, 77900, Olomouc, Czech Republic
| | - Zbyněk Milec
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 31, 77900, Olomouc, Czech Republic
| | - Jan Šafář
- Institute of Experimental Botany, Czech Academy of Sciences, Centre of the Region Haná for Biotechnological and Agricultural Research, Šlechtitelů 31, 77900, Olomouc, Czech Republic.
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20
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Cheng X, Pan M, E Z, Zhou Y, Niu B, Chen C. Functional divergence of two duplicated Fertilization Independent Endosperm genes in rice with respect to seed development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:124-137. [PMID: 33463824 DOI: 10.1111/tpj.14911] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 05/14/2020] [Accepted: 06/26/2020] [Indexed: 05/22/2023]
Abstract
Fertilization Independent Endosperm (FIE) is an essential member of Polycomb Repressive Complex 2 (PRC2) that plays important roles in the developmental regulation of plants. OsFIE1 and OsFIE2 are two FIE homologs in the rice genome. Here, we showed that OsFIE1 probably duplicated from OsFIE2 after the origin of the tribe Oryzeae, but has a specific expression pattern and methylation landscape. During evolution, OsFIE1 underwent a less intensive purifying selection than did OsFIE2. The mutant osfie1 produced smaller seeds and displayed reduced dormancy, indicating that OsFIE1 predominantly functions in late seed development. Ectopic expression of OsFIE1, but not OsFIE2, was deleterious to vegetative growth in a dose-dependent manner. The newly evolved N-terminal tail of OsFIE1 was probably not the cause of the adverse effects on vegetative growth. The CRISPR/Cas9-derived mutant osfie2 exhibited impaired cellularization of the endosperm, which suggested that OsFIE2 is indispensable for early seed development as a positive regulator of cellularization. Autonomous endosperm was observed in both OsFIE2+- and osfie1/OsFIE2+- but at a very low frequency. Although OsFIE1-PRC2 exhibited H3K27me3 methyltransferase ability in plants, OsFIE1-PRC2 is likely to be less important for development in rice than is OsFIE2-PRC2. Our findings revealed the functional divergence of OsFIE1 and OsFIE2 and shed light on their distinct evolution following duplication.
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Affiliation(s)
- Xiaojun Cheng
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, College of Agriculture, Yangzhou University, Yangzhou, China
| | - Meiyao Pan
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, College of Agriculture, Yangzhou University, Yangzhou, China
| | - Zhiguo E
- Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, China
| | - Yong Zhou
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, College of Agriculture, Yangzhou University, Yangzhou, China
| | - Baixiao Niu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, College of Agriculture, Yangzhou University, Yangzhou, China
| | - Chen Chen
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, College of Agriculture, Yangzhou University, Yangzhou, China
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21
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Olsen OA. The Modular Control of Cereal Endosperm Development. TRENDS IN PLANT SCIENCE 2020; 25:279-290. [PMID: 31956036 DOI: 10.1016/j.tplants.2019.12.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 11/20/2019] [Accepted: 12/06/2019] [Indexed: 05/05/2023]
Abstract
Expansion of the human population demands a significant increase in cereal production. The main component of cereal grains is endosperm, a body of starchy endosperm (SE) cells surrounded by aleurone (AL) cells with transfer cells (TC) at the base and embryo surrounding (ESR) cells adjacent to the embryo. The data reviewed here emphasize the modular nature of endosperm by first suggesting that sucrose promotes development of the fertilized triploid endosperm cell. Next, that the basal syncytial endosperm responds to glucose by turning on TC development. The default endosperm cell fate is SE and ESR differentiation is likely activated by signaling from the embryo. Cells on the exterior surface of the endosperm are specified as AL cells.
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Affiliation(s)
- Odd-Arne Olsen
- Department of Plant Science, Norwegian University of Life Sciences, 1434, Ås, Norway.
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22
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Ni J, Ma X, Feng Y, Tian Q, Wang Y, Xu N, Tang J, Wang G. Updating and interaction of polycomb repressive complex 2 components in maize (Zea mays). PLANTA 2019; 250:573-588. [PMID: 31127375 DOI: 10.1007/s00425-019-03193-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 05/16/2019] [Indexed: 06/09/2023]
Abstract
The information on core components in maize polycomb repressive complex 2 (PRC2) are updated at a genome-wide scale, and the protein-protein interaction networks of PRC2 components are further provided in maize. The evolutionarily conserved polycomb group (PcG) proteins form multi-subunits polycomb repressive complexes (PRCs) that repress gene expression via chromatin condensation. In Arabidopsis, three distinct PRC2s have been identified, each determining a specific developmental program with partly functional redundancy. However, the core components and biological functions of PRC2 in cereals remain obscure. Here, we updated the information on maize PRC2 components at a genome-wide scale. Maize PRC2 subunits are highly duplicated, with five MSI1, three E(z), two ESC and two Su(z)12 homologs. ZmFIE1 is preferentially expressed in the endosperm, whereas the remaining are broadly expressed in many tissues. ZmCLF/MEZ1 and ZmFIE1 are maternally expressed imprinted genes, in contrast to the paternal-dominantly expression of ZmFIE2 in the endosperm. In maize, E(z) members likely provide a scaffold for assembling PRC2 complexes, whereas Su(z)12 and p55/MSI1-like proteins together reinforce the complex; ESC members probably determine its specificity: FIE1-PRC2 regulates endosperm cell development, whereas FIE2-PRC2 controls other cell types. The duplicated Brassicaceae-specific MEA and FIS2 also directly interact with maize PRC2 members. Together, this study establishes a roadmap for protein-protein interactions of maize PRC2 components, providing new insights into their functions in the growth and development of cereals.
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Affiliation(s)
- Jiacheng Ni
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai, 200444, China
| | - Xuexia Ma
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai, 200444, China
| | - Yu Feng
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai, 200444, China
| | - Qiuzhen Tian
- Key Laboratory of Wheat and Maize Crops Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Yongyan Wang
- Key Laboratory of Wheat and Maize Crops Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Ningkun Xu
- Key Laboratory of Wheat and Maize Crops Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Jihua Tang
- Key Laboratory of Wheat and Maize Crops Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Guifeng Wang
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai, 200444, China.
- Key Laboratory of Wheat and Maize Crops Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China.
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Begcy K, Dresselhaus T. Epigenetic responses to abiotic stresses during reproductive development in cereals. PLANT REPRODUCTION 2018; 31:343-355. [PMID: 29943158 PMCID: PMC6244825 DOI: 10.1007/s00497-018-0343-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 06/22/2018] [Indexed: 05/03/2023]
Abstract
KEY MESSAGE Overview of current understanding of epigenetic alterations after abiotic stresses during reproductive development in cereals. Abiotic stresses, including heat, drought, cold, flooding, and salinity, negatively impact crop productivity. Various stages during reproductive development are especially sensitive to environmental stresses, which may lead to complete sterility and severe yield losses. Plants exhibit diverse responses to ameliorate stress damage. Changes in DNA methylation, histone modification as well as regulation of small RNA and long noncoding RNA pathways have been shown to represent key modulators in plant stress responses. During reproductive development in cereals, various protein complexes controlling histone and DNA methylation have been identified, revealing conserved and novel mechanisms regulating abiotic stress responses in cereals and other plant species. New findings highlight the role of transposable elements during stress periods. Here, we review our current understanding of epigenetic stress responses during male and female gametophyte formation (germline development), fertilization, early seed devolvement, and seed maturation in cereals. An integrative model of epigenetic responses during reproductive development in cereals is proposed, emphasizing the role of DNA methylation and histone modifications during abiotic stresses.
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Affiliation(s)
- Kevin Begcy
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93053, Regensburg, Germany.
| | - Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93053, Regensburg, Germany.
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24
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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.
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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
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25
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Affiliation(s)
- Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, Yokohama, Kanagawa, Japan.
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26
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Tonosaki K, Sekine D, Ohnishi T, Ono A, Furuumi H, Kurata N, Kinoshita T. Overcoming the species hybridization barrier by ploidy manipulation in the genus Oryza. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 93:534-544. [PMID: 29271099 DOI: 10.1111/tpj.13803] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 11/16/2017] [Accepted: 11/27/2017] [Indexed: 05/21/2023]
Abstract
In most eudicot and monocot species, interspecific and interploidy crosses generally display abnormalities in the endosperm that are the major cause of a post-zygotic hybridization barrier. In some eudicot species, however, this type of hybridization barrier can be overcome by the manipulation of ploidy levels of one parental species, suggesting that the molecular mechanisms underlying the species hybridization barrier can be circumvented by genome dosage. We previously demonstrated that endosperm barriers in interspecific and interploidy crosses in the genus Oryza involve overlapping but different mechanisms. This result contrasts with those in the genus Arabidopsis, which shows similar outcomes in both interploidy and interspecific crosses. Therefore, we postulated that an exploration of pathways for overcoming the species hybridization barrier in Oryza endosperm, by manipulating the ploidy levels in one parental species, might provide novel insights into molecular mechanisms. We showed that fertile hybrid seeds could be produced by an interspecific cross of female tetraploid Oryza sativa and male diploid Oryza longistaminata. Although the rate of nuclear divisions did not return to normal levels in the hybrid endosperm, the timing of cellularization, nucellus degeneration and the accumulation of storage products were close to normal levels. In addition, the expression patterns of the imprinted gene MADS87 and YUCCA11 were changed when the species barrier was overcome. These results suggest that the regulatory machinery for developmental transitions and imprinted gene expression are likely to play a central role in overcoming species hybridization barriers by genome dosage in the genus Oryza.
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Affiliation(s)
- Kaoru Tonosaki
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka Totsuka, Yokohama, Kanagawa, 244-0813, Japan
| | - Daisuke Sekine
- Institute of Crop Science, National Agriculture and Food Research Organization (NARO), 2-1-18 Kannondai, Tsukuba, Ibaraki, 305-8602, Japan
| | - Takayuki Ohnishi
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka Totsuka, Yokohama, Kanagawa, 244-0813, Japan
- Center for Education and Research of Community Collaboration, Utsunomiya University, 350 Mine, Utsunomiya, Tochigi, 321-8505, Japan
| | - Akemi Ono
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka Totsuka, Yokohama, Kanagawa, 244-0813, Japan
| | - Hiroyasu Furuumi
- Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka, 411-8540, Japan
| | - Nori Kurata
- Genetic Strains Research Center, National Institute of Genetics, Mishima, Shizuoka, 411-8540, Japan
| | - Tetsu Kinoshita
- Kihara Institute for Biological Research, Yokohama City University, 641-12 Maioka Totsuka, Yokohama, Kanagawa, 244-0813, Japan
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27
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Wang G, Köhler C. Epigenetic processes in flowering plant reproduction. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:797-807. [PMID: 28062591 DOI: 10.1093/jxb/erw486] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Seeds provide up to 70% of the energy intake of the human population, emphasizing the relevance of understanding the genetic and epigenetic mechanisms controlling seed formation. In flowering plants, seeds are the product of a double fertilization event, leading to the formation of the embryo and the endosperm surrounded by maternal tissues. Analogous to mammals, plants undergo extensive epigenetic reprogramming during both gamete formation and early seed development, a process that is supposed to be required to enforce silencing of transposable elements and thus to maintain genome stability. Global changes of DNA methylation, histone modifications, and small RNAs are closely associated with epigenome programming during plant reproduction. Here, we review current knowledge on chromatin changes occurring during sporogenesis and gametogenesis, as well as early seed development in major flowering plant models.
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Affiliation(s)
- Guifeng Wang
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Claudia Köhler
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
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28
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Abstract
Apomixis, commonly defined as asexual reproduction through seed, is a reproductive trait that occurs in only a few minor crops, but would be highly valuable in major crops. Apomixis results in seed-derived progenies that are genetically identical to their maternal parent. The advantage of apomixis would lie in seed propagation of elite food, feed, and biofuel crops that are heterozygous such as hybrid corn and switchgrass or self-pollinating crops for which no commercial-scale hybrid production system is available. While hybrid plants often outperform parental lines in growth and higher yields, production of hybrid seed is accomplished through carefully controlled, labor intensive crosses. Both small farmers in developing countries who produce their own seed and commercial companies that market hybrid seed could benefit from the establishment of engineered apomixis in plants. In this chapter, we review what has been learned from studying natural apomicts and mutations in sexual plants leading to apomixis-like development, plus discuss how the components of apomixis could be successfully engineered in plants.
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Affiliation(s)
- Joann A Conner
- Horticulture Department, NESPAL/University of Georgia-Tifton Campus, 2356 Rainwater Road, Tifton, GA, 31794, USA.
| | - Peggy Ozias-Akins
- Horticulture Department, NESPAL/University of Georgia-Tifton Campus, 2356 Rainwater Road, Tifton, GA, 31794, USA
- Institute of Plant Breeding, Genetics and Genomics, University of Georgia-Tifton Campus, Tifton, GA, USA
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29
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Nonogaki H. Seed Biology Updates - Highlights and New Discoveries in Seed Dormancy and Germination Research. FRONTIERS IN PLANT SCIENCE 2017; 8:524. [PMID: 28443117 PMCID: PMC5387071 DOI: 10.3389/fpls.2017.00524] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 03/24/2017] [Indexed: 05/05/2023]
Abstract
An understanding of the biology of seeds has been greatly advanced in recent years. The progresses, particularly in the field of seed dormancy and germination research, have been made at a remarkable speed. Some of the possible epigenetic mechanisms, including an involvement of non-coding RNA, which were predicted for DELAY OF GERMINATION1 just a few years ago, have now been demonstrated with strong molecular and genetic evidence. Imprinting, or parent-of-origin-specific gene silencing/expression, which was characterized particularly for developing seeds, was also found in imbibed seeds and suggested for dormancy mechanisms. Hormone biology in seeds, which is the most advanced and almost a traditional area of seed research, also presents a new dimension. Upstream regulators of hormone metabolism and hormone transporters, such as abscisic acid and gibberellin influx/efflux carriers, have been identified. Characterization of the novel posttranslational modification pathways, including the N-end rule and S-nitrosylation pathways, which play a critical role in turnover of the major hormone signal transduction proteins, also expanded our knowledge about the complexity of hormone signaling in seeds. These progresses made at the molecular level are significant steps toward a better understanding of how seeds translate soil and other environmental signals into their internal hormone biology and make an important decision to stay dormant or commence with germination.
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30
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Hands P, Rabiger DS, Koltunow A. Mechanisms of endosperm initiation. PLANT REPRODUCTION 2016; 29:215-25. [PMID: 27450467 PMCID: PMC4978757 DOI: 10.1007/s00497-016-0290-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 07/14/2016] [Indexed: 05/21/2023]
Abstract
KEY MESSAGE Overview of developmental events and signalling during central cell maturation and early endosperm development with a focus on mechanisms of sexual and autonomous endosperm initiation. Endosperm is important for seed viability and global food supply. The mechanisms regulating the developmental transition between Female Gametophyte (FG) maturation and early endosperm development in angiosperms are difficult to study as they occur buried deep within the ovule. Knowledge of the molecular events underlying this developmental window of events has significantly increased with the combined use of mutants, cell specific markers, and plant hormone sensing reporters. Here, we review recent discoveries concerning the developmental events and signalling of FG maturation, fertilization, and endosperm development. We focus on the regulation of the initiation of endosperm development with and without fertilization in Arabidopsis and the apomict Hieracium, comparing this to what is known in monocots where distinct differences in developmental patterning may underlie alternative mechanisms of suppression and initiation. The Polycomb Repressive Complex 2 (PRC2), plant hormones, and transcription factors are iteratively involved in early fertilization-induced endosperm formation in Arabidopsis. Auxin increases and PRC2 complex inactivation can also induce fertilization-independent endosperm proliferation in Arabidopsis. Function of the PRC2 complex member FERTILIZATION-INDEPENDENT ENDOSPERM and two loci AutE and LOP are required for autonomous endosperm development in apomictic Hieracium. A comparative understanding of cues required for early endosperm development will facilitate genetic engineering approaches for the development of resilient seed crops, especially if an option for fertilization-independent endosperm formation was possible to combat stress-induced crop failure.
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Affiliation(s)
- Philip Hands
- CSIRO Agriculture and Food, Commonwealth Scientific and Industrial Research Organization, Private Bag 2, Glen Osmond, SA, 5064, Australia
| | - David S Rabiger
- CSIRO Agriculture and Food, Commonwealth Scientific and Industrial Research Organization, Private Bag 2, Glen Osmond, SA, 5064, Australia
| | - Anna Koltunow
- CSIRO Agriculture and Food, Commonwealth Scientific and Industrial Research Organization, Private Bag 2, Glen Osmond, SA, 5064, Australia.
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31
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Furihata HY, Suenaga K, Kawanabe T, Yoshida T, Kawabe A. Gene duplication, silencing and expression alteration govern the molecular evolution of PRC2 genes in plants. Genes Genet Syst 2016; 91:85-95. [PMID: 27074982 DOI: 10.1266/ggs.15-00055] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PRC2 genes were analyzed for their number of gene duplications, dN/dS ratios and expression patterns among Brassicaceae and Gramineae species. Although both amino acid sequences and copy number of the PRC2 genes were generally well conserved in both Brassicaceae and Gramineae species, we observed that some rapidly evolving genes experienced duplications and expression pattern changes. After multiple duplication events, all but one or two of the duplicated copies tend to be silenced. Silenced copies were reactivated in the endosperm and showed ectopic expression in developing seeds. The results indicated that rapid evolution of some PRC2 genes is initially caused by a relaxation of selective constraint following the gene duplication events. Several loci could become maternally expressed imprinted genes and acquired functional roles in the endosperm.
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32
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Yan S, Wu G. Predicting Crystallization Propensity of Proteins from Arabidopsis Thaliana. Biol Proced Online 2015; 17:16. [PMID: 26604856 PMCID: PMC4657326 DOI: 10.1186/s12575-015-0029-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 11/12/2015] [Indexed: 12/02/2022] Open
Abstract
Background Many studies have correlated characteristics of amino acids with crystallization propensity, as part of the effort to determine the factors that affect the propensity of protein crystallization. However, these characteristics are constant; that is, the encoded amino acid sequences have the same value for each type of amino acid. To overcome this inflexibility, three dynamic characteristics of amino acids and protein were introduced to analyze the crystallization propensity of proteins. Both logistic regression and neural network models were used to correlate each of two dynamic characteristics with the crystallization propensity of 301 proteins from Arabidopsis thaliana, and their results were compared with those obtained from each of 531 constant amino acid characteristics, which served as the benchmark. Results The neural network model was more powerful for predicting the crystallization propensity of proteins than the logistic regression model. Compared with the benchmark, the dynamic characteristics of amino acids provided good prediction results for the crystallization propensity, and the distribution probability gave the highest sensitivity. Using 90 % accuracy as a cutoff point, the predictable portion of A. thaliana portions was ranked, and the statistical analysis showed that the larger the predictable portion, the better the prediction. Conclusions These results demonstrate that dynamic characteristics have a certain relationship with the crystallization propensity, and they could be helpful for the prediction of protein crystallization, which may provide a theoretical concept for certain proteins before conducting experimental crystallization. Electronic supplementary material The online version of this article (doi:10.1186/s12575-015-0029-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shaomin Yan
- State Key Laboratory of Non-food Biomass Enzyme Technology, National Engineering Research Center for Non-food Biorefinery, Guangxi Key Laboratory of Biorefinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi 530007 China
| | - Guang Wu
- State Key Laboratory of Non-food Biomass Enzyme Technology, National Engineering Research Center for Non-food Biorefinery, Guangxi Key Laboratory of Biorefinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi 530007 China
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