1
|
Nguyen NH, Ho PTB, Le LTT. Revisit and explore the ethylene-independent mechanism of sex expression in cucumber (Cucumis sativus). PLANT REPRODUCTION 2024:10.1007/s00497-024-00501-1. [PMID: 38598160 DOI: 10.1007/s00497-024-00501-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 03/22/2024] [Indexed: 04/11/2024]
Abstract
KEY MESSAGE This review provides a thorough and comprehensive perspective on the topic of cucumber sexual expression. Specifically, insights into sex expression mediated by pathways other than ethylene are highlighted. Cucumber (Cucumis sativus L.) is a common and important commercial crop that is cultivated and consumed worldwide. Additionally, this species is commonly used as a model for investigating plant sex expression. Cucumbers exhibit a variety of floral arrangements, comprising male, female, and hermaphroditic (bisexual) flowers. Generally, cucumber plants that produce female flowers are typically preferred due to their significant impact on the overall output. Various environmental conditions, such as temperature, light quality, and photoperiod, have been also shown to influence the sex expression in this species. Multiple lines of evidence indicate that ethylene and its biosynthesis genes are crucial in regulating cucumber sex expression. Gibberellins, another well-known phytohormone, can similarly influence cucumber sex expression via an ethylene-independent route. Further studies employing the next-generation sequencing technology also visualized a deeper slice of the molecular mechanism such as the role of the cell cycle program in the cucumber sex expression. This review aims to provide an overview of the sex expression of cucumber including its underlying molecular mechanism and regulatory aspects based on recent investigations.
Collapse
Affiliation(s)
- Nguyen Hoai Nguyen
- Faculty of Biotechnology, Ho Chi Minh City Open University, Ho Chi Minh City, Vietnam
| | - Phuong Thi Bich Ho
- Faculty of Biotechnology, Ho Chi Minh City Open University, Ho Chi Minh City, Vietnam
| | - Linh Thi Truc Le
- Faculty of Biotechnology, Ho Chi Minh City Open University, Ho Chi Minh City, Vietnam.
| |
Collapse
|
2
|
Liang M, Huai B, Lin J, Liang X, He H, Bai M, Wu H. Ca2+- and Zn2+-dependent nucleases co-participate in nuclear DNA degradation during programmed cell death in secretory cavity development in Citrus fruits. TREE PHYSIOLOGY 2024; 44:tpad122. [PMID: 37738622 DOI: 10.1093/treephys/tpad122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/06/2023] [Accepted: 09/19/2023] [Indexed: 09/24/2023]
Abstract
Calcium (Ca2+)- and zinc Zn2+-dependent nucleases play pivotal roles in plant nuclear DNA degradation in programmed cell death (PCD). However, the mechanisms by which these two nucleases co-participate in PCD-associated nuclear DNA degradation remain unclear. Here, the spatiotemporal expression patterns of two nucleases (CrCAN and CrENDO1) were analyzed qualitatively and quantitatively during PCD in secretory cavity formation in Citrus reticulata 'Chachi' fruits. Results show that the middle and late initial cell stages and lumen-forming stages are key stages for nuclear degradation during the secretory cavity development. CAN and ENDO1 exhibited potent in vitro DNA degradation activity at pH 8.0 and pH 5.5, respectively. Quantitative real-time reverse-transcription polymerase chain reaction, in situ hybridization assays, the subcellular localization of Ca2+ and Zn2+, and immunocytochemical localization showed that CrCAN was activated at the middle and late initial cell stages, while CrENDO1 was activated at the late initial cell and lumen-forming stages. Furthermore, we used immunocytochemical double-labelling to simultaneously locate CrCAN and CrENDO1. The DNA degradation activity of the two nucleases was verified by simulating the change of intracellular pH in vitro. Our results also showed that CrCAN and CrENDO1 worked respectively and co-participated in nuclear DNA degradation during PCD of secretory cavity cells. In conclusion, we propose the model for the synergistic effect of Ca2+- and Zn2+-dependent nucleases (CrCAN and CrENDO1) in co-participating in nuclear DNA degradation during secretory cavity cell PCD in Citrus fruits. Our findings provide direct experimental evidence for exploring different ion-dependent nucleases involved in nuclear degradation during plant PCD.
Collapse
Affiliation(s)
- Minjian Liang
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Wushan Road, Guangzhou 510642, China
- College of Biology and Food Engineering, Guangdong University of Education, Guangzhou 510303, China
| | - Bin Huai
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Wushan Road, Guangzhou 510642, China
| | - Junjun Lin
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Wushan Road, Guangzhou 510642, China
| | - Xiangxiu Liang
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Wushan Road, Guangzhou 510642, China
| | - Hanjun He
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Wushan Road, Guangzhou 510642, China
- Guangdong Technology Research Center for Traditional Chinese Veterinary Medicine and Natural Medicine, South China Agricultural University, Wushan Road, Guangzhou 510642, China
| | - Mei Bai
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Wushan Road, Guangzhou 510642, China
- Guangdong Technology Research Center for Traditional Chinese Veterinary Medicine and Natural Medicine, South China Agricultural University, Wushan Road, Guangzhou 510642, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, South China Agricultural University, Wushan Road, Guangzhou 510642, China
| | - Hong Wu
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Wushan Road, Guangzhou 510642, China
- Guangdong Technology Research Center for Traditional Chinese Veterinary Medicine and Natural Medicine, South China Agricultural University, Wushan Road, Guangzhou 510642, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, South China Agricultural University, Wushan Road, Guangzhou 510642, China
| |
Collapse
|
3
|
Aparna, Skarzyńska A, Pląder W, Pawełkowicz M. Impact of Climate Change on Regulation of Genes Involved in Sex Determination and Fruit Production in Cucumber. PLANTS (BASEL, SWITZERLAND) 2023; 12:2651. [PMID: 37514264 PMCID: PMC10385340 DOI: 10.3390/plants12142651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/06/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023]
Abstract
Environmental changes, both natural and anthropogenic, mainly related to rising temperatures and water scarcity, are clearly visible around the world. Climate change is important for crop production and is a major issue for the growth and productivity of cucumbers. Processes such as sex determination, flower morphogenesis and fruit development in cucumbers are highly sensitive to various forms of stress induced by climatic changes. It is noteworthy that many factors, including genetic factors, transcription factors, phytohormones and miRNAs, are crucial in regulating these processes and are themselves affected by climate change. Changes in the expression and activity of these factors have been observed as a consequence of climatic conditions. This review focuses primarily on exploring the effects of climate change and abiotic stresses, such as increasing temperature and drought, on the processes of sex determination, reproduction, and fruit development in cucumbers at the molecular level. In addition, it highlights the existing research gaps that need to be addressed in order to improve our understanding of the complex interactions between climate change and cucumber physiology. This, in turn, may lead to strategies to mitigate the adverse effects and enhance cucumber productivity in a changing climate.
Collapse
Affiliation(s)
- Aparna
- Department of Plant Genetics, Breeding and Biotechnology, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland
| | - Agnieszka Skarzyńska
- Department of Plant Genetics, Breeding and Biotechnology, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland
| | - Wojciech Pląder
- Department of Plant Genetics, Breeding and Biotechnology, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland
| | - Magdalena Pawełkowicz
- Department of Plant Genetics, Breeding and Biotechnology, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland
| |
Collapse
|
4
|
Luo H, Zhang H, Wang H. Advance in sex differentiation in cucumber. FRONTIERS IN PLANT SCIENCE 2023; 14:1186904. [PMID: 37265638 PMCID: PMC10231686 DOI: 10.3389/fpls.2023.1186904] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/20/2023] [Indexed: 06/03/2023]
Abstract
Cucumber belongs to the family Cucurbitaceae (melon genus) and is an annual herbaceous vegetable crop. Cucumber is an important cash crop that is grown all over the world. From morphology to cytology, from canonical genetics to molecular biology, researchers have performed much research on sex differentiation and its regulatory mechanism in cucumber, mainly in terms of cucumber sex determination genes, environmental conditions, and the effects of plant hormones, revealing its genetic basis to improve the number of female flowers in cucumber, thus greatly improving the yield of cucumber. This paper reviews the research progress of sex differentiation in cucumber in recent years, mainly focusing on sex-determining genes, environmental conditions, and the influence of phytohormones in cucumber, and provides a theoretical basis and technical support for the realization of high and stable yield cultivation and molecular breeding of cucumber crop traits.
Collapse
Affiliation(s)
- Haiyan Luo
- Key Laboratory for Quality and Safety Control of Subtropical Fruits and Vegetables, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Hangzhou Lin’an District Agricultural and Rural Bureau, Hangzhou, China
| | - Huanchun Zhang
- Yantai Institute of Agricultural Sciences, Yantai, China
| | - Huasen Wang
- Key Laboratory for Quality and Safety Control of Subtropical Fruits and Vegetables, Collaborative Innovation Center for Efficient and Green Production of Agriculture in Mountainous Areas of Zhejiang Province, Ministry of Agriculture and Rural Affairs, College of Horticulture Science, Zhejiang Agriculture and Forestry University, Hangzhou, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, College of Horticulture, Qingdao Agricultural University, Qingdao, China
| |
Collapse
|
5
|
N. D. V, Matsumura H, Munshi AD, Ellur RK, Chinnusamy V, Singh A, Iquebal MA, Jaiswal S, Jat GS, Panigrahi I, Gaikwad AB, Rao AR, Dey SS, Behera TK. Molecular mapping of genomic regions and identification of possible candidate genes associated with gynoecious sex expression in bitter gourd. FRONTIERS IN PLANT SCIENCE 2023; 14:1071648. [PMID: 36938036 PMCID: PMC10017754 DOI: 10.3389/fpls.2023.1071648] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
Bitter gourd is an important vegetable crop grown throughout the tropics mainly because of its high nutritional value. Sex expression and identification of gynoecious trait in cucurbitaceous vegetable crops has facilitated the hybrid breeding programme in a great way to improve productivity. In bitter gourd, gynoecious sex expression is poorly reported and detailed molecular pathways involve yet to be studied. The present experiment was conducted to study the inheritance, identify the genomic regions associated with gynoecious sex expression and to reveal possible candidate genes through QTL-seq. Segregation for the gynoecious and monoecious sex forms in the F2 progenies indicated single recessive gene controlling gynoecious sex expression in the genotype, PVGy-201. Gynoecious parent, PVGy-201, Monoecious parent, Pusa Do Mausami (PDM), and two contrasting bulks were constituted for deep-sequencing. A total of 10.56, 23.11, 15.07, and 19.38 Gb of clean reads from PVGy-201, PDM, gynoecious bulk and monoecious bulks were generated. Based on the ΔSNP index, 1.31 Mb regions on the chromosome 1 was identified to be associated with gynoecious sex expression in bitter gourd. In the QTL region 293,467 PVGy-201 unique variants, including SNPs and indels, were identified. In the identified QTL region, a total of 1019 homozygous variants were identified between PVGy1 and PDM genomes and 71 among them were non-synonymous variants (SNPS and INDELs), out of which 11 variants (7 INDELs, 4 SNPs) were classified as high impact variants with frame shift/stop gain effect. In total twelve genes associated with male and female gametophyte development were identified in the QTL-region. Ethylene-responsive transcription factor 12, Auxin response factor 6, Copper-transporting ATPase RAN1, CBL-interacting serine/threonine-protein kinase 23, ABC transporter C family member 2, DEAD-box ATP-dependent RNA helicase 1 isoform X2, Polygalacturonase QRT3-like isoform X2, Protein CHROMATIN REMODELING 4 were identified with possible role in gynoecious sex expression. Promoter region variation in 8 among the 12 genes indicated their role in determining gynoecious sex expression in bitter gourd genotype, DBGy-1. The findings in the study provides insight about sex expression in bitter gourd and will facilitate fine mapping and more precise identification of candidate genes through their functional validation.
Collapse
Affiliation(s)
- Vinay N. D.
- Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Hideo Matsumura
- Gene Research Centre, Shinshu University, Ueda, Nagano, Japan
| | - Anilabha Das Munshi
- Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Ranjith Kumar Ellur
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Viswanathan Chinnusamy
- Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Ankita Singh
- Centre for Agricultural Bioinformatics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India
| | - Mir Asif Iquebal
- Centre for Agricultural Bioinformatics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India
| | - Sarika Jaiswal
- Centre for Agricultural Bioinformatics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India
| | - Gograj Singh Jat
- Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Ipsita Panigrahi
- Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Ambika Baladev Gaikwad
- Division of Genomic Resources, ICAR-National Bureau of Plant Genetic Resources, New Delhi, India
| | - A. R. Rao
- Centre for Agricultural Bioinformatics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India
| | - Shyam Sundar Dey
- Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Tusar Kanti Behera
- Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, New Delhi, India
- ICAR-Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh, India
| |
Collapse
|
6
|
Zhu BS, Zhu YX, Zhang YF, Zhong X, Pan KY, Jiang Y, Wen CK, Yang ZN, Yao X. Ethylene Activates the EIN2- EIN3/EIL1 Signaling Pathway in Tapetum and Disturbs Anther Development in Arabidopsis. Cells 2022; 11:cells11193177. [PMID: 36231139 PMCID: PMC9563277 DOI: 10.3390/cells11193177] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 10/08/2022] [Accepted: 10/08/2022] [Indexed: 11/17/2022] Open
Abstract
Ethylene was previously reported to repress stamen development in both cucumber and Arabidopsis. Here, we performed a detailed analysis of the effect of ethylene on anther development. After ethylene treatment, stamens but not pistils display obvious developmental defects which lead to sterility. Both tapetum and microspores (or microsporocytes) degenerated after ethylene treatment. In ein2-1 and ein3-1 eil1-1 mutants, ethylene treatment did not affect their fertility, indicating the effects of ethylene on anther development are mediated by EIN2 and EIN3/EIL1 in vivo. The transcription of EIN2 and EIN3 are activated by ethylene in the tapetum layer. However, ectopic expression of EIN3 in tapetum did not induce significant anther defects, implying that the expression of EIN3 are regulated post transcriptional level. Consistently, ethylene treatment induced the accumulation of EIN3 in the tapetal cells. Thus, ethylene not only activates the transcription of EIN2 and EIN3, but also stabilizes of EIN3 in the tapetum to disturb its development. The expression of several ethylene related genes was significantly increased, and the expression of the five key transcription factors required for tapetum development was decreased after ethylene treatment. Our results thus point out that ethylene inhibits anther development through the EIN2-EIN3/EIL1 signaling pathway. The activation of this signaling pathway in anther wall, especially in the tapetum, induces the degeneration of the tapetum and leads to pollen abortion.
Collapse
Affiliation(s)
- Ben-Shun Zhu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
- Development Center of Plant Germplasm Resources, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Ying-Xiu Zhu
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Yan-Fei Zhang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
- Development Center of Plant Germplasm Resources, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Xiang Zhong
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Keng-Yu Pan
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Yu Jiang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Chi-Kuang Wen
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Zhong-Nan Yang
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
- Development Center of Plant Germplasm Resources, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
- Correspondence: (Z.-N.Y.); (X.Y.)
| | - Xiaozhen Yao
- Shanghai Key Laboratory of Plant Molecular Sciences, College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
- Correspondence: (Z.-N.Y.); (X.Y.)
| |
Collapse
|
7
|
Li Y, Liu H, Yao X, Sun L, Sui X. The Role of Sugar Transporter CsSWEET7a in Apoplasmic Phloem Unloading in Receptacle and Nectary During Cucumber Anthesis. FRONTIERS IN PLANT SCIENCE 2022; 12:758526. [PMID: 35173746 PMCID: PMC8841823 DOI: 10.3389/fpls.2021.758526] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 12/31/2021] [Indexed: 06/01/2023]
Abstract
During anthesis, there is an increased demand for carbohydrates due to pollen maturation and nectary secretion that warrants a systematic phloem unloading strategy for sugar partitioning. Sugar transporters are key components of the apoplasmic phloem unloading strategy and control the sugar flux needed for plant development. Currently, the phloem unloading strategy during anthesis has not been explored in cucumber, and the question of which sugar transporters are active during flower anthesis is poorly understood. In this study, a study utilizing the phloem-mobile symplasmic tracer carboxyfluorescein (CF) suggested that the phloem unloading was symplasmically isolated in the receptacle and nectary of cucumber flowers at anthesis. We also identified a hexose transporter that is highly expressed in cucumber flower, Sugar Will Eventually be Exported Transporter 7a (SWEET7a). CsSWEET7a was mainly expressed in receptacle and nectary tissues in both male and female flowers, where its expression level increased rapidly right before anthesis. At anthesis, the CsSWEET7a protein was specifically localized to the phloem region of the receptacle and nectary, indicating that CsSWEET7a may function in the apoplasmic phloem unloading during flower anthesis. Although cucumber mainly transports raffinose family oligosaccharides (RFOs) in the phloem, sucrose, glucose, and fructose are the major sugars in the flower receptacle and the nectary as well as in nectar at anthesis. In addition, the transcript levels of genes encoding soluble sugar hydrolases (α-galactosidase, sucrose synthase, cytoplasmic invertase, and cell wall invertase) were correlated with that of CsSWEET7a. These results indicated that CsSWEET7a may be involved in sugar partitioning as an exporter in the phloem of the receptacle and nectary to supply carbohydrates for flower anthesis and nectar secretion in cucumber.
Collapse
|
8
|
Zhang H, Li S, Yang L, Cai G, Chen H, Gao D, Lin T, Cui Q, Wang D, Li Z, Cai R, Bai S, Lucas WJ, Huang S, Zhang Z, Sun J. Gain-of-function of the 1-aminocyclopropane-1-carboxylate synthase gene ACS1G induces female flower development in cucumber gynoecy. THE PLANT CELL 2021; 33:306-321. [PMID: 33793793 PMCID: PMC8136878 DOI: 10.1093/plcell/koaa018] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 11/03/2020] [Indexed: 05/06/2023]
Abstract
Unisexual flowers provide a useful system for studying plant sex determination. In cucumber (Cucumis sativus L.), three major Mendelian loci control unisexual flower development, Female (F), androecious [a; 1-aminocyclopropane-1-carboxylate {ACC} synthase 11, acs11], and Monoecious (M; ACS2), referred to here as the Female, Androecious, Monoecious (FAM) model, in combination with two genes, gynoecious (g, the WIP family C2H2 zinc finger transcription factor gene WIP1) and the ethylene biosynthetic gene ACC oxidase 2 (ACO2). The F locus, conferring gynoecy and the potential for increasing fruit yield, is defined by a 30.2-kb tandem duplication containing three genes. However, the gene that determines the Female phenotype, and its mechanism, remains unknown. Here, we created a set of mutants and revealed that ACS1G is responsible for gynoecy conferred by the F locus. The duplication resulted in ACS1G acquiring a new promoter and expression pattern; in plants carrying the F locus duplication, ACS1G is expressed early in floral bud development, where it functions with ACO2 to generate an ethylene burst. The resulting ethylene represses WIP1 and activates ACS2 to initiate gynoecy. This early ACS1G expression bypasses the need for ACS11 to produce ethylene, thereby establishing a dominant pathway for female floral development. Based on these findings, we propose a model for how these ethylene biosynthesis genes cooperate to control unisexual flower development in cucumber.
Collapse
Affiliation(s)
- Huimin Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences,
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry
of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics,
Beijing 100081, China
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural
Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences,
Shenzhen 518124, China
| | - Shuai Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences,
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry
of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics,
Beijing 100081, China
| | - Li Yang
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural
Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences,
Shenzhen 518124, China
- College of Horticulture and Forestry, Huazhong Agricultural University and Key
Laboratory of Horticultural Plant Biology, Ministry of Education, Wuhan
430070, China
| | - Guanghua Cai
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural
Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences,
Shenzhen 518124, China
| | - Huiming Chen
- Hunan Vegetable Research Institute, Hunan Academy of Agricultural
Science, Changsha 410125, China
| | - Dongli Gao
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural
Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences,
Shenzhen 518124, China
| | - Tao Lin
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural
Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences,
Shenzhen 518124, China
| | - Qingzhi Cui
- Hunan Vegetable Research Institute, Hunan Academy of Agricultural
Science, Changsha 410125, China
| | - Donghui Wang
- College of Life Sciences, Peking University, Beijing 100871,
China
| | - Zheng Li
- College of Horticulture, Northwest A&F University, Shaanxi
712100, China
| | - Run Cai
- School of Agriculture and Biology, Shanghai Jiao Tong University,
Shanghai 200240, China
| | - Shunong Bai
- College of Life Sciences, Peking University, Beijing 100871,
China
| | - William J Lucas
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural
Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences,
Shenzhen 518124, China
- College of Biological Sciences, University of California, Davis,
CA 95616, USA
| | - Sanwen Huang
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural
Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences,
Shenzhen 518124, China
| | - Zhonghua Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences,
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry
of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics,
Beijing 100081, China
- College of Horticulture, Qingdao Agricultural University, Qingdao
266109, China
| | - Jinjing Sun
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences,
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry
of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics,
Beijing 100081, China
- Authors for correspondence: ,
| |
Collapse
|
9
|
Bai SN. Are unisexual flowers an appropriate model to study plant sex determination? JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:4625-4628. [PMID: 32367137 PMCID: PMC7410173 DOI: 10.1093/jxb/eraa207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 04/28/2020] [Indexed: 05/27/2023]
Affiliation(s)
- Shu-Nong Bai
- State Key Laboratory of Protein & Plant Gene Research, Quantitative Biology Center, College of Life Sciences, Peking University, Beijing, China
| |
Collapse
|
10
|
Bai M, Liang M, Huai B, Gao H, Tong P, Shen R, He H, Wu H. Ca2+-dependent nuclease is involved in DNA degradation during the formation of the secretory cavity by programmed cell death in fruit of Citrus grandis 'Tomentosa'. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:4812-4827. [PMID: 32324220 PMCID: PMC7410178 DOI: 10.1093/jxb/eraa199] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/21/2020] [Indexed: 05/09/2023]
Abstract
The secretory cavity is a typical structure in Citrus fruit and is formed by schizolysigeny. Previous reports have indicated that programmed cell death (PCD) is involved in the degradation of secretory cavity cells in the fruit, and that the spatio-temporal location of calcium is closely related to nuclear DNA degradation in this process; however, the molecular mechanisms underlying this Ca2+ regulation remain largely unknown. Here, we identified CgCaN that encodes a Ca2+-dependent DNase in the fruit of Citrus grandis 'Tomentosa', the function of which was studied using calcium ion localization, DNase activity assays, in situ hybridization, and protein immunolocalization. The results suggested that the full-length cDNA of CgCaN contains an ORF of 1011 bp that encodes a protein 336 amino acids in length with a SNase-like functional domain. CgCaN digests dsDNA at neutral pH in a Ca2+-dependent manner. In situ hybridization signals of CgCaN were particularly distributed in the secretory cavity cells. Ca2+ and Ca2+-dependent DNases were mainly observed in the condensed chromatin and in the nucleolus. In addition, spatio-temporal expression patterns of CgCaN and its protein coincided with the time-points that corresponded to chromatin degradation and nuclear rupture during the PCD in the development of the fruit secretory cavity. Taken together, our results suggest that Ca2+-dependent DNases play direct roles in nuclear DNA degradation during the PCD of secretory cavity cells during Citrus fruit development. Given the consistency of the expression patterns of genes regulated by calmodulin (CaM) and calcium-dependent protein kinases (CDPK) and the dynamics of calcium accumulation, we speculate that CaM and CDPK proteins might be involved in Ca2+ transport from the extracellular walls through the cytoplasm and into the nucleus to activate CgCaN for DNA degradation.
Collapse
Affiliation(s)
- Mei Bai
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Minjian Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Bin Huai
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Han Gao
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Panpan Tong
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Rongxin Shen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Hanjun He
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
| | - Hong Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou, China
- Correspondence:
| |
Collapse
|
11
|
Abstract
Zhi-Hong Xu is a plant physiologist who studied botany at Peking University (1959–1965). He joined the Shanghai Institute of Plant Physiology (SIPP), Chinese Academy of Sciences (CAS), as a graduate student in 1965. He recalls what has happened for the institute, during the Cultural Revolution, and he witnessed the spring of science eventually coming to China. Xu was a visiting scholar at the John Innes Institute and in the Department of Botany at Nottingham University in the United Kingdom (1979–1981). He became deputy director of SIPP in 1983 and director in 1991; he also chaired the State Key Laboratory of Plant Molecular Genetics SIPP (1988–1996). He worked as a visiting scientist in the Institute of Molecular and Cell Biology, National University of Singapore, for three months each year (1989–1992). He served as vice president of CAS (1992–2002) and as president of Peking University (1999–2008). Over these periods he was heavily involved in the design and implementation of major scientific projects in life sciences and agriculture in China. He is an academician of CAS and member of the Academy of Sciences for the Developing World. His scientific contributions mainly cover plant tissue culture, hormone mechanism in development, as well as plant developmental response to environment. Xu, as a scientist and leader who has made an impact in the community, called up a lot of excellent young scientists returning to China. His efforts have promoted the fast development of China's plant and agricultural sciences.
Collapse
Affiliation(s)
- Zhi-Hong Xu
- School of Life Sciences, Peking University, Beijing 100871, China
- Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| |
Collapse
|
12
|
Sui W, Guo K, Li L, Liu S, Takano T, Zhang X. Arabidopsis Ca 2+-dependent nuclease AtCaN2 plays a negative role in plant responses to salt stress. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 281:213-222. [PMID: 30824054 DOI: 10.1016/j.plantsci.2018.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/16/2018] [Accepted: 12/08/2018] [Indexed: 06/09/2023]
Abstract
Eukaryotic nucleases are involved in processes such as DNA restriction digestion, repair, recombination, transposition, and programmed cell death (PCD). Studies on the role of nucleases have mostly focused on PCD during plant development, while the information on nucleases involved in responses to different abiotic stress conditions remains limited. Here, we identified a Ca2+-dependent nuclease, AtCaN2, in Arabidopsis thaliana and characterized its activity, expression patterns, and involvement in plant responses to salt stress. AtCaN2 showed a dual endonuclease and exonuclease activity, being able to degrade circular plasmids, RNA, single-stranded DNA, and double-stranded DNA. Expression analysis showed that AtCaN2 was strongly induced in senescent siliques and by salt stress. Overexpression of AtCaN2 decreased the plant tolerance to salt stress conditions, leading to an excessive H2O2 accumulation. However, an atcan2 mutant showed better tolerance to salt stress and a lower level of H2O2 accumulation. Moreover, the expression of several genes (AtAPX1, AtGPX8, and AtSOD1), encoding reactive oxygen species-scavenging enzymes (ascorbate peroxidase 1, glutathione peroxidase 8, and superoxide dismutase 1, respectively), was highly induced in the atcan2 mutant under salt stress conditions. In addition, salt-stress-induced cell death was increased in the AtCaN2-overexpressing transgenic plant but decreased in the atcan2 mutant. On the basis of these findings, we conclude that AtCaN2 plays a negative role in plant tolerance to salt stress. A AtCaN2 knock out could reduce ROS accumulation, decrease ROS-induced PCD, and improve overall plant tolerance.
Collapse
Affiliation(s)
- Wenting Sui
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Harbin 150040, China
| | - Kunyuan Guo
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Harbin 150040, China
| | - Li Li
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Harbin 150040, China
| | - Shenkui Liu
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 311300, China
| | - Tetsuo Takano
- Asian Natural Environment Science Center (ANESC), The University of Tokyo, 1-1-1 Midori Cho, Nishitokyo-shi, Tokyo 188-0002, Japan
| | - Xinxin Zhang
- Key Laboratory of Saline-Alkali Vegetation Ecology Restoration (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Harbin 150040, China.
| |
Collapse
|
13
|
Li D, Sheng Y, Niu H, Li Z. Gene Interactions Regulating Sex Determination in Cucurbits. FRONTIERS IN PLANT SCIENCE 2019; 10:1231. [PMID: 31649699 PMCID: PMC6796545 DOI: 10.3389/fpls.2019.01231] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 09/05/2019] [Indexed: 05/13/2023]
Abstract
The family Cucurbitaceae includes many economically important crops, such as cucumber (Cucumis sativus), melon (Cucumis melo), watermelon (Citrullus lanatus), and zucchini (Cucurbita pepo), which share homologous gene pathways that control similar phenotypes. Sex determination is a research hotspot associated with yield and quality, and the genes involved are highly orthologous and conserved in cucurbits. In the field, six normal sex types have been categorized according to the distribution of female, male, or bisexual flowers in a given plant. To date, five orthologous genes involved in sex determination have been cloned, and their various combinations and expression patterns can explain all the identified sex types. In addition to genetic mechanisms, ethylene controls sex expression in this family. Two ethylene signaling components have been identified recently, which will help us to explore the ethylene signaling-mediated interactions among sex-related genes. This review discusses recent advances relating to the mechanism of sex determination in cucurbits and the prospects for research in this area.
Collapse
Affiliation(s)
- Dandan Li
- College of Horticulture and Landscape Architecture, Heilongjiang Bayi Agriculture University, Daqing, China
| | - Yunyan Sheng
- College of Horticulture and Landscape Architecture, Heilongjiang Bayi Agriculture University, Daqing, China
| | - Huanhuan Niu
- College of Horticulture, Northwest A&F University, Yangling, China
| | - Zheng Li
- College of Horticulture, Northwest A&F University, Yangling, China
| |
Collapse
|
14
|
Lai YS, Shen D, Zhang W, Zhang X, Qiu Y, Wang H, Dou X, Li S, Wu Y, Song J, Ji G, Li X. Temperature and photoperiod changes affect cucumber sex expression by different epigenetic regulations. BMC PLANT BIOLOGY 2018; 18:268. [PMID: 30400867 PMCID: PMC6220452 DOI: 10.1186/s12870-018-1490-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Accepted: 10/19/2018] [Indexed: 05/25/2023]
Abstract
BACKGROUND Cucumbers (Cucumis sativus) are known for their plasticity in sex expression. DNA methylation status determines gene activity but is susceptible to environmental condition changes. Thus, DNA methylation-based epigenetic regulation may at least partially account for the instability of cucumber sex expression. Do temperature and photoperiod that are the two most important environmental factors have equal effect on cucumber sex expression by similar epigenetic regulation mechanism? To answer this question, we did a two-factor experiment of temperature and photoperiod and generated methylome and transcriptome data from cucumber shoot apices. RESULTS The seasonal change in the femaleness of a cucumber core germplasm collection was investigated over five consecutive years. As a result, 71.3% of the 359 cucumber accessions significantly decreased their femaleness in early autumn when compared with spring. High temperature and long-day photoperiod treatments, which mimic early autumn conditions, are both unfavorable for female flower formation, and temperature is the predominant factor. High temperatures and long-day treatments both predominantly resulted in hypermethylation compared to demethylation, and temperature effect was decisive. The targeted cytosines shared in high-temperature and long-day photoperiod treatment showed the same change in DNA methylation level. Moreover, differentially expressed TEs (DETs) and the predicted epiregulation sites were clustered across chromosomes, and importantly, these sites were reproducible among different treatments. Essentially, the photoperiod treatment preferentially and significantly influenced flower development processes, while temperature treatment produced stronger responses from phytohormone-pathway-related genes. Cucumber AGAMOUS was likely epicontrolled exclusively by photoperiod while CAULIFLOWER A and CsACO3 were likely epicontrolled by both photoperiod and temperature. CONCLUSIONS Seasonal change of sex expression is a germplasm-wide phenomenon in cucumbers. High temperature and long-day photoperiod might have the same effect on the methylome via the same mechanism of gene-TE interaction but resulted in different epicontrol sites that account for different mechanisms between temperature- and photoperiod-dependent sex expression changes.
Collapse
Affiliation(s)
- Yun-Song Lai
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, 611130, China
| | - Di Shen
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Wei Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xiaohui Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yang Qiu
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Haiping Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xinxin Dou
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Sigeng Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yuanqi Wu
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jiangping Song
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Guanyu Ji
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xixiang Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| |
Collapse
|
15
|
Wang DH, Song W, Wei SW, Zheng YF, Chen ZS, Han JD, Zhang HT, Luo JC, Qin YM, Xu ZH, Bai SN. Characterization of the Ubiquitin C-Terminal Hydrolase and Ubiquitin-Specific Protease Families in Rice ( Oryza sativa). FRONTIERS IN PLANT SCIENCE 2018; 9:1636. [PMID: 30498503 PMCID: PMC6249995 DOI: 10.3389/fpls.2018.01636] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/22/2018] [Indexed: 05/11/2023]
Abstract
The ubiquitin C-terminal hydrolase (UCH) and ubiquitin-specific processing protease (UBP) protein families both function in protein deubiquitination, playing important roles in a wide range of biological processes in animals, fungi, and plants. Little is known about the functions of these proteins in rice (Oryza sativa), and the numbers of genes reported for these families have not been consistent between different rice database resources. To further explore their functions, it is necessary to first clarify the basic molecular and biochemical nature of these two gene families. Using a database similarity search, we clarified the numbers of genes in these two families in the rice genome, examined the enzyme activities of their corresponding proteins, and characterized the expression patterns of all OsUCH and representative OsUBP genes. Five OsUCH and 44 OsUBP genes were identified in the rice genome, with four OsUCH proteins and 10 of 16 tested representative OsUBP proteins showing enzymatic activities. Two OsUCHs and five OsUBPs were found to be preferentially expressed in the early development of rice stamens. This work thus lays down a reliable bioinformatic foundation for future investigations of genes in these two families, particularly for exploring their potential roles in rice stamen development.
Collapse
Affiliation(s)
- Dong-Hui Wang
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Wei Song
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Shao-Wei Wei
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Ya-Feng Zheng
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Zhi-Shan Chen
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Jing-Dan Han
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Hong-Tao Zhang
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Jing-Chu Luo
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Yong-Mei Qin
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Zhi-Hong Xu
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
| | - Shu-Nong Bai
- State Key Laboratory of Protein and Plant Gene Research, College of Life Science, Peking University, Beijing, China
- National Center of Plant Gene Research, Beijing, China
- *Correspondence: Shu-Nong Bai,
| |
Collapse
|
16
|
Pan J, Wang G, Wen H, Du H, Lian H, He H, Pan J, Cai R. Differential Gene Expression Caused by the F and M Loci Provides Insight Into Ethylene-Mediated Female Flower Differentiation in Cucumber. FRONTIERS IN PLANT SCIENCE 2018; 9:1091. [PMID: 30154805 PMCID: PMC6102477 DOI: 10.3389/fpls.2018.01091] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/05/2018] [Indexed: 05/06/2023]
Abstract
In cucumber (Cucumis sativus L.), the differentiation and development of female flowers are important processes that directly affect the fruit yield and quality. Sex differentiation is mainly controlled by three ethylene synthase genes, F (CsACS1G), M (CsACS2), and A (CsACS11). Thus, ethylene plays a key role in the sex differentiation in cucumber. The "one-hormone hypothesis" posits that F and M regulate the ethylene levels and initiate female flower development in cucumber. Nonetheless, the precise molecular mechanism of this process remains elusive. To investigate the mechanism by which F and M regulate the sex phenotype, three cucumber near-isogenic lines, namely H34 (FFmmAA, hermaphroditic), G12 (FFMMAA, gynoecious), and M12 (ffMMAA, monoecious), with different F and M loci were generated. The transcriptomic analysis of the apical shoots revealed that the expression of the B-class floral homeotic genes, CsPI (Csa4G358770) and CsAP3 (Csa3G865440), was immensely suppressed in G12 (100% female flowers) but highly expressed in M12 (∼90% male flowers). In contrast, CAG2 (Csa1G467100), which is an AG-like C-class floral homeotic gene, was specifically highly expressed in G12. Thus, the initiation of female flowers is likely to be caused by the downregulation of B-class and upregulation of C-class genes by ethylene production in the floral primordium. Additionally, CsERF31, which was highly expressed in G12, showed temporal and spatial expression patterns similar to those of M and responded to the ethylene-related chemical treatments. The biochemical experiments further demonstrated that CsERF31 could directly bind the promoter of M and promote its expression. Thus, CsERF31 responded to the ethylene signal derived from F and mediated the positive feedback regulation of ethylene by activating M expression, which offers an extended "one-hormone hypothesis" of sex differentiation in cucumber.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Run Cai
- *Correspondence: Junsong Pan, ; Run Cai,
| |
Collapse
|
17
|
Lai YS, Zhang X, Zhang W, Shen D, Wang H, Xia Y, Qiu Y, Song J, Wang C, Li X. The association of changes in DNA methylation with temperature-dependent sex determination in cucumber. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:2899-2912. [PMID: 28498935 DOI: 10.1093/jxb/erx144] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 04/13/2017] [Indexed: 05/26/2023]
Abstract
Cucumber (Cucumis sativus L.) is characterized by its diverse and flexible sexual types. Here, we evaluated the effect of low temperature (LT) exposure on cucumber femaleness under short-day conditions. Shoot apices were subjected to whole-genome bisulfate sequencing (WGBS), mRNA-seq, and sRNA-seq. The results showed that temperature had a substantial and global impact on transposable element (TE)-related small RNA-directed DNA methylation (RdDM) mechanisms, resulting in large amounts of CHH-type cytosine demethylation. In the cucumber genome, TEs are common in regions near genes that are also subject to DNA demethylation. TE-gene interactions showed very strong reactions to LT treatment, as nearly 80% of the differentially methylated regions (DMRs) were distributed in genic regions. Demethylation near genes led to the co-ordinated expression of genes and TEs. More importantly, genome-wide de novo methylation changes also resulted in small amounts of CG- and CHG-type DMRs. Methylation changes in CG-DMRs located <600 bp from the transcription start and end sites (TSSs/TESs) negatively correlated with transcription changes in differentially expressed genes (DEGs), probably indicating epiregulation. Ethylene is called the 'sex hormone' of cucumbers. We observed the up-regulation of ethylene biosynthesis-related CsACO3 and the down-regulation of an Arabidopsis RAP2.4-like ethylene-responsive (AP2/ERF) transcription factor, demonstrating the inferred epiregulation. Our study characterized the response of the apex methylome to LT and predicted the possible epiregulation of temperature-dependent sex determination (TSD) in cucumber.
Collapse
Affiliation(s)
- Yun-Song Lai
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
- Institute of Pomology & Olericulture, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiaohui Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Wei Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Di Shen
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Haiping Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yudong Xia
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yang Qiu
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiangping Song
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Chenchen Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xixiang Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| |
Collapse
|
18
|
Sun JJ, Li F, Wang DH, Liu XF, Li X, Liu N, Gu HT, Zou C, Luo JC, He CX, Huang SW, Zhang XL, Xu ZH, Bai SN. CsAP3: A Cucumber Homolog to Arabidopsis APETALA3 with Novel Characteristics. FRONTIERS IN PLANT SCIENCE 2016; 7:1181. [PMID: 27540391 PMCID: PMC4972961 DOI: 10.3389/fpls.2016.01181] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 07/22/2016] [Indexed: 05/11/2023]
Abstract
In our previous efforts to understand the regulatory mechanisms of cucumber unisexual flower development, we observed a stamen-specific down-regulation of the ethylene receptor CsETR1 in stage 6 female flowers of cucumber (Cucumis sativus L.). This down-regulation is correlated with the primordial anther-specific DNA damage that characterizes inappropriate stamen development in cucumber female flowers. To understand how CsETR1 is down regulated in the stamen, we characterized a cucumber MADS box gene homologous to Arabidopsis AP3, CsAP3. We demonstrated that CsAP3 is functionally equivalent to the Arabidopsis B-class MADS gene AP3. However, three novel characteristics of CsAP3 were found. These include firstly, binding and activating CsETR1 promoter in vitro and in vivo; secondly, containing a GV repeat in its C-terminus, which is conserved in cucurbits and required for the transcription activation; and thirdly, decreased expression as the node number increases, which is similar to that found for CsETR1. These findings revealed not only the conserved function of CsAP3 as a B-class floral identity gene, but also its unique functions in regulation of female flower development in cucumber.
Collapse
Affiliation(s)
- Jin-Jing Sun
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural SciencesBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
| | - Feng Li
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
| | - Dong-Hui Wang
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
| | - Xiao-Feng Liu
- Department of Vegetable Sciences, Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
| | - Xia Li
- College of Life Sciences, Peking UniversityBeijing, China
| | - Na Liu
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
| | - Hai-Tao Gu
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
| | - Cheng Zou
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
| | - Jing-Chu Luo
- College of Life Sciences, Peking UniversityBeijing, China
| | - Chao-Xing He
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural SciencesBeijing, China
| | - San-Wen Huang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural SciencesBeijing, China
| | - Xiao-Lan Zhang
- Department of Vegetable Sciences, Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, China Agricultural UniversityBeijing, China
| | - Zhi-Hong Xu
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
| | - Shu-Nong Bai
- State Key Laboratory of Protein and Plant Gene ResearchBeijing, China
- College of Life Sciences, Peking UniversityBeijing, China
- National Center of Plant Gene ResearchBeijing, China
- *Correspondence: Shu-Nong Bai,
| |
Collapse
|
19
|
Chen R, Shen LP, Wang DH, Wang FG, Zeng HY, Chen ZS, Peng YB, Lin YN, Tang X, Deng MH, Yao N, Luo JC, Xu ZH, Bai SN. A Gene Expression Profiling of Early Rice Stamen Development that Reveals Inhibition of Photosynthetic Genes by OsMADS58. MOLECULAR PLANT 2015; 8:1069-89. [PMID: 25684654 DOI: 10.1016/j.molp.2015.02.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 01/28/2015] [Accepted: 02/03/2015] [Indexed: 05/19/2023]
Abstract
Stamen is a unique plant organ wherein germ cells or microsporocytes that commit to meiosis are initiated from somatic cells during its early developmental process. While genes determining stamen identity are known according to the ABC model of floral development, little information is available on how these genes affect germ cell initiation. By using the Affymetrix GeneChip Rice Genome Array to assess 51 279 transcripts, we established a dynamic gene expression profile (GEP) of the early developmental process of rice (Oryza sativa) stamen. Systematic analysis of the GEP data revealed novel expression patterns of some developmentally important genes including meiosis-, tapetum-, and phytohormone-related genes. Following the finding that a substantial amount of nuclear genes encoding photosynthetic proteins are expressed at the low levels in early rice stamen, through the ChIP-seq analysis we found that a C-class MADS box protein, OsMADS58, binds many nuclear-encoded genes participated in photosystem and light reactions and the expression levels of most of them are increased when expression of OsMADS58 is downregulated in the osmads58 mutant. Furthermore, more pro-chloroplasts are observed and increased signals of reactive oxygen species are detected in the osmads58 mutant anthers. These findings implicate a novel link between stamen identity determination and hypoxia status establishment.
Collapse
Affiliation(s)
- Rui Chen
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Li-Ping Shen
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Dong-Hui Wang
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Fu-Gui Wang
- Center for Quantitative Biology, Peking University, Beijing 100871, China; School of Mathematical Sciences, Peking University, Beijing 100871, China
| | - Hong-Yun Zeng
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhi-Shan Chen
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Yi-Ben Peng
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Ya-Nan Lin
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Xing Tang
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China; Center for Bioinformatics, Peking University, Beijing 100871, China
| | - Ming-Hua Deng
- Center for Quantitative Biology, Peking University, Beijing 100871, China; School of Mathematical Sciences, Peking University, Beijing 100871, China
| | - Nan Yao
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Jing-Chu Luo
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China; Center for Bioinformatics, Peking University, Beijing 100871, China
| | - Zhi-Hong Xu
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China
| | - Shu-Nong Bai
- Center for Quantitative Biology, Peking University, Beijing 100871, China; The National Center of Plant Gene Research, Beijing 100871, China; State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, 624 Jin-Guang Life Science Building, 5 Yiheyuan Road, Beijing 100871, China.
| |
Collapse
|
20
|
Gu H, Overstreet AMC, Yang Y. Exosomes Biogenesis and Potentials in Disease Diagnosis and Drug Delivery. ACTA ACUST UNITED AC 2014. [DOI: 10.1142/s1793984414410177] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Exosomes were discovered more than 30 years ago. Only recently has their importance been recognized for intercellular communication. Exosomes, with their size ranging from 30 nm to 100 nm, are lipid bilayer nanoparticles and secreted by many different types of cells with versatile functions. Exosomes contain macromolecules and exist in various body fluids, including blood, urine, milk and ascites fluid. Due to their specific property, exosomes are very promising in the fields of disease diagnosis and therapy. Nanotechnology is a great tool that will be helpful in basic research and the application of exosomes. Here, we briefly review the function and potential use of exosomes in nanomedicine.
Collapse
Affiliation(s)
- Haitao Gu
- Department of Pharmacology & Cell Biophysics University of Cincinnati, College of Medicine, Cincinnati, OH 45267, USA
| | - Anne-Marie C. Overstreet
- Department of Cancer and Cell Biology, University of Cincinnati, College of Medicine, Cincinnati, OH 45267, USA
| | - Yongguang Yang
- Department of Cancer and Cell Biology, University of Cincinnati, College of Medicine, Cincinnati, OH 45267, USA
| |
Collapse
|
21
|
Sakamoto W, Takami T. Nucleases in higher plants and their possible involvement in DNA degradation during leaf senescence. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:3835-43. [PMID: 24634485 DOI: 10.1093/jxb/eru091] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
During leaf senescence, macromolecules such as proteins and lipids are known to be degraded for redistribution into upper tissues. Similarly, nucleic acids appear to undergo fragmentation or degradation during senescence, but the physiological role of nucleic acid degradation, particularly of genomic DNA degradation, remains unclear. To date, more than a dozen of plant deoxyribonucleases have been reported, whereas it remains to be verified whether any of them degrade DNA during leaf senescence. This review summarizes current knowledge related to the plant nucleases that are induced developmentally or in a tissue-specific manner and are known to degrade DNA biochemically. Of these, several endonucleases (BFN1, CAN1, and CAN2) and an exonuclease (DPD1) in Arabidopsis seem to act in leaf senescence because they were shown to be inducible at the transcript level. This review specifically examines DPD1, which is dual-targeted to chloroplasts and mitochondria. Results show that, among the exonuclease family to which DPD1 belongs, DPD1 expression is extraordinary when estimated using a microarray database. DPD1 is the only example among the nucleases in which DNA degradation has been confirmed in vivo in pollen by mutant analysis. These data imply a significant role of organelle DNA degradation during leaf senescence and implicate DPD1 as a potential target for deciphering nucleotide salvage in plants.
Collapse
Affiliation(s)
- Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| | - Tsuneaki Takami
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama 710-0046, Japan
| |
Collapse
|
22
|
Sánchez-Pons N, Vicient CM. Identification of a type I Ca2+/Mg2+-dependent endonuclease induced in maize cells exposed to camptothecin. BMC PLANT BIOLOGY 2013; 13:186. [PMID: 24256432 PMCID: PMC4225560 DOI: 10.1186/1471-2229-13-186] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 11/16/2013] [Indexed: 05/24/2023]
Abstract
BACKGROUND Camptothecin is a plant alkaloid that specifically binds topoisomerase I, inhibiting its activity and inducing double stranded breaks in DNA and activating the cell responses to DNA damage. RESULTS Maize cultured cells were incubated in the presence of different concentrations of camptothecin. Camptothecin inhibits cultured cell growth, induces genomic DNA degradation, and induces a 32 kDa Ca2+/Mg2+-dependent nuclease activity. This nuclease, we called CaMNUC32, is inhibited by Zn2+ and by acid pH, it is mainly localized in the nucleus and it cleaves single- and double-stranded DNA, with a higher activity against single-stranded DNA. Two-dimensional electrophoresis combined with mass spectrometry suggests that CaMNUC32 is a member of the type I S1/P1 nuclease family. This type of nucleases are usually Zn2+-dependent but our results support previous indications that S1-type nucleases have a wide variety of enzyme activities, including Ca2+/Mg2+-dependent. CONCLUSIONS We have identified and characterized CaMNUC32, a 32 kDa Ca2+/Mg2+-dependent nuclease of the S1/P1 family induced by the topoisomerase I inhibitor camptothecin in maize cultured cells.
Collapse
Affiliation(s)
- Núria Sánchez-Pons
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics CRAG (CSIC-IRTA-UAB-UB), Campus UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona, Spain
| | - Carlos M Vicient
- Department of Molecular Genetics, Centre for Research in Agricultural Genomics CRAG (CSIC-IRTA-UAB-UB), Campus UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona, Spain
| |
Collapse
|
23
|
Unisexual cucumber flowers, sex and sex differentiation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 304:1-55. [PMID: 23809434 DOI: 10.1016/b978-0-12-407696-9.00001-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Sex is a universal phenomenon in the world of eukaryotes. Attempts have been made to understand regulatory mechanisms for plant sex determination by investigating unisexual flowers. The cucumber plant is one of the model systems for studying how sex determination is regulated by phytohormones. A systematic investigation of the development of unisexual cucumber flowers is summarized here, and it is suggested that the mechanism of the unisexual flower can help us to understand how the process leading to one type of gametogenesis is prevented. Based on these findings, we concluded that the unisexual cucumber flowers is not an issue of sex differentiation, but instead a mechanism for avoiding self-pollination. Sex differentiation is essentially the divergent point(s) leading to heterogametogenesis. On the basis of analyses of sex differentiation in unicellular organisms and animals as well as the core process of plant life cycle, a concept of "sexual reproduction cycle" is proposed for understanding the essential role of sex and a "progressive model" for future investigations of sex differentiation in plants.
Collapse
|
24
|
Leśniewicz K, Poręba E, Smolarkiewicz M, Wolff N, Stanisławski S, Wojtaszek P. Plant plasma membrane-bound staphylococcal-like DNases as a novel class of eukaryotic nucleases. BMC PLANT BIOLOGY 2012; 12:195. [PMID: 23102437 PMCID: PMC3505149 DOI: 10.1186/1471-2229-12-195] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 10/22/2012] [Indexed: 05/22/2023]
Abstract
BACKGROUND The activity of degradative nucleases responsible for genomic DNA digestion has been observed in all kingdoms of life. It is believed that the main function of DNA degradation occurring during plant programmed cell death is redistribution of nucleic acid derived products such as nitrogen, phosphorus and nucleotide bases. Plant degradative nucleases that have been studied so far belong mainly to the S1-type family and were identified in cellular compartments containing nucleic acids or in the organelles where they are stored before final application. However, the explanation of how degraded DNA components are exported from the dying cells for further reutilization remains open. RESULTS Bioinformatic and experimental data presented in this paper indicate that two Arabidopsis staphylococcal-like nucleases, named CAN1 and CAN2, are anchored to the cell membrane via N-terminal myristoylation and palmitoylation modifications. Both proteins possess a unique hybrid structure in their catalytic domain consisting of staphylococcal nuclease-like and tRNA synthetase anticodon binding-like motifs. They are neutral, Ca2+-dependent nucleaces showing a different specificity toward the ssDNA, dsDNA and RNA substrates. A study of microarray experiments and endogenous nuclease activity revealed that expression of CAN1 gene correlates with different forms of programmed cell death, while the CAN2 gene is constitutively expressed. CONCLUSIONS In this paper we present evidence showing that two plant staphylococcal-like nucleases belong to a new, as yet unidentified class of eukaryotic nucleases, characterized by unique plasma membrane localization. The identification of this class of nucleases indicates that plant cells possess additional, so far uncharacterized, mechanisms responsible for DNA and RNA degradation. The potential functions of these nucleases in relation to their unique intracellular location are discussed.
Collapse
Affiliation(s)
- Krzysztof Leśniewicz
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, 89 Umultowska St, Poznan 61-614, Poland
| | - Elżbieta Poręba
- Department of Molecular Virology, Institute of Experimental Biology, Adam Mickiewicz University, Poznań, 89 Umultowska St, Poznan, 61-614, Poland
| | - Michalina Smolarkiewicz
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, 89 Umultowska St, Poznan 61-614, Poland
| | - Natalia Wolff
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, 89 Umultowska St, Poznan 61-614, Poland
| | - Sławoj Stanisławski
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, 89 Umultowska St, Poznan 61-614, Poland
| | - Przemysław Wojtaszek
- Department of Molecular and Cellular Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, 89 Umultowska St, Poznan 61-614, Poland
| |
Collapse
|
25
|
Li Z, Wang S, Tao Q, Pan J, Si L, Gong Z, Cai R. A putative positive feedback regulation mechanism in CsACS2 expression suggests a modified model for sex determination in cucumber (Cucumis sativus L.). JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:4475-84. [PMID: 22577183 PMCID: PMC3421985 DOI: 10.1093/jxb/ers123] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 03/27/2012] [Accepted: 04/04/2012] [Indexed: 05/21/2023]
Abstract
It is well established that the plant hormone ethylene plays a key role in cucumber sex determination. Since the unisexual control gene M was cloned and shown to encode an ethylene synthase, instead of an ethylene receptor, the 'one-hormone hypothesis', which was used to explain the cucumber sex phenotype, has been challenged. Here, the physiological function of CsACS2 (the gene encoded by the M locus) was studied using the transgenic tobacco system. The results indicated that overexpression of CsACS2 increased ethylene production in the tobacco plant, and the native cucumber promoter had no activity in transgenic tobacco (PM). However, when PM plants were treated with exogenous ethylene, CsACS2 expression could be detected. In cucumber, ethylene treatment could also induce transcription of CsACS2, while inhibition of ethylene action reduced the expression level. These findings suggest a positive feedback regulation mechanism for CsACS2, and a modified 'one-hormone hypothesis' for sex determination in cucumber is proposed.
Collapse
Affiliation(s)
- Zheng Li
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
- School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China
| | - Shu Wang
- College of Horticulture and Landscape Architecture, Southwest Forest University, Kunming, Yunnan 650224, China
| | - Qianyi Tao
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
- School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China
| | - Junsong Pan
- School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China
| | - Longting Si
- College of Horticulture, Shenyang Agriculture University, Shenyang, Liaoning 110161, China
| | - Zhenhui Gong
- College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Run Cai
- School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China
| |
Collapse
|
26
|
Chen HM, Pang Y, Zeng J, Ding Q, Yin SY, Liu C, Lu MZ, Cui KM, He XQ. The Ca2+ -dependent DNases are involved in secondary xylem development in Eucommia ulmoides. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2012; 54:456-70. [PMID: 22694768 DOI: 10.1111/j.1744-7909.2012.01134.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Secondary xylem development has long been recognized as a typical case of programmed cell death (PCD) in plants. During PCD, the degradation of genomic DNA is catalyzed by endonucleases. However, to date, no endonuclease has been shown to participate in secondary xylem development. Two novel Ca(2+) -dependent DNase genes, EuCaN1 and EuCaN2, were identified from the differentiating secondary xylem of the tree Eucommia ulmoides Oliv., their functions were studied by DNase activity assay, in situ hybridization, protein immunolocalization and virus-induced gene silencing experiments. Full-length cDNAs of EuCaN1 and EuCaN2 contained an open reading frame of 987 bp, encoding two proteins of 328 amino acids with SNase-like functional domains. The genomic DNA sequence for EuCaN1 had no introns, while EuCaN2 had 8 introns. EuCaN1 and EuCaN2 digested ssDNA and dsDNA with Ca(2+) -dependence at neutral pH. Their expression was confined to differentiating secondary xylem cells and the proteins were localized in the nucleus. Their activity dynamics was closely correlated with secondary xylem development. Secondary xylem cell differentiation is influenced by RNAi of endonuclease genes. The results provide evidence that the Ca(2+) -dependent DNases are involved in secondary xylem development.
Collapse
Affiliation(s)
- Hui-Min Chen
- State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, China
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Bai SN, Xu ZH. Bird-nest puzzle: can the study of unisexual flowers such as cucumber solve the problem of plant sex determination? PROTOPLASMA 2012; 249 Suppl 2:S119-23. [PMID: 22415162 DOI: 10.1007/s00709-012-0396-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Accepted: 02/29/2012] [Indexed: 05/09/2023]
Abstract
Unisexual flower development has long been used as a model system to understand the mechanism of plant sex determination. However, based on our investigation of the mechanisms regulating the development of unisexual cucumber flowers, we have realized that understanding how organ development is inhibited may not necessarily reveal how an organ is formed. We refer to this problem as a "bird-nest puzzle," meaning one cannot understand how a bird lays and hatches its eggs by understanding how its nest is ruined. To understand the biological significance of unisexual flowers, we reexamine the original meaning of sex and its application in plants. Additionally, we propose that the fundamental biological advantage for the selection and maintenance of unisexual flowers during evolution is to promote cross pollination.
Collapse
Affiliation(s)
- Shu-Nong Bai
- PKU-Yale Joint Research Center of Agricultural and Plant Molecular Biology, State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, 5 Yiheyuan Road, Beijing 100871, People's Republic of China.
| | | |
Collapse
|