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Xu Y, Tian W, Yin M, Cai Z, Zhang L, Yuan D, Yi H, Wu J. The miR159a-DUO1 module regulates pollen development by modulating auxin biosynthesis and starch metabolism in citrus. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2024; 66:1351-1369. [PMID: 38578168 DOI: 10.1111/jipb.13656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Accepted: 03/15/2024] [Indexed: 04/06/2024]
Abstract
Achieving seedlessness in citrus varieties is one of the important objectives of citrus breeding. Male sterility associated with abnormal pollen development is an important factor in seedlessness. However, our understanding of the regulatory mechanism underlying the seedlessness phenotype in citrus is still limited. Here, we determined that the miR159a-DUO1 module played an important role in regulating pollen development in citrus, which further indirectly modulated seed development and fruit size. Both the overexpression of csi-miR159a and the knocking out of DUO1 in Hong Kong kumquat (Fortunella hindsii) resulted in small and seedless fruit phenotypes. Moreover, pollen was severely aborted in both transgenic lines, with arrested pollen mitotic I and abnormal pollen starch metabolism. Through additional cross-pollination experiments, DUO1 was proven to be the key target gene for miR159a to regulate male sterility in citrus. Based on DNA affinity purification sequencing (DAP-seq), RNA-seq, and verified interaction assays, YUC2/YUC6, SS4 and STP8 were identified as downstream target genes of DUO1, those were all positively regulated by DUO1. In transgenic F. hindsii lines, the miR159a-DUO1 module down-regulated the expression of YUC2/YUC6, which decreased indoleacetic acid (IAA) levels and modulated auxin signaling to repress pollen mitotic I. The miR159a-DUO1 module reduced the expression of the starch synthesis gene SS4 and sugar transport gene STP8 to disrupt starch metabolism in pollen. Overall, this work reveals a new mechanism by which the miR159a-DUO1 module regulates pollen development and elucidates the molecular regulatory network underlying male sterility in citrus.
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Affiliation(s)
- Yanhui Xu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
| | - Wenxiu Tian
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
| | - Minqiang Yin
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhenmei Cai
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
| | - Li Zhang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
| | - Deyi Yuan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees of the Ministry of Education and Key Laboratory of Non-Wood Forest Products of the Forestry Ministry, Central South University of Forestry and Technology, Changsha, 410004, China
| | - Hualin Yi
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
| | - Juxun Wu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, China
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Liu L, Zhang J, Xu J, Li Y, Lv H, Wang F, Guo J, Lin T, Zhao B, Li XX, Guo YD, Zhang N. SlMYC2 promotes SlLBD40-mediated cell expansion in tomato fruit development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 118:1872-1888. [PMID: 38481350 DOI: 10.1111/tpj.16715] [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: 03/12/2023] [Revised: 02/19/2024] [Accepted: 02/29/2024] [Indexed: 06/14/2024]
Abstract
As a plant-specific transcription factor, lateral organ boundaries domain (LBD) protein was reported to regulate plant growth and stress response, but the functional research of subfamily II genes is limited. SlMYC2, a master regulator of Jasmonic acid response, has been found to exhibit high expression levels in fruit and has been implicated in the regulation of fruit ripening and resistance to Botrytis. However, its role in fruit expansion remains unknown. In this study, we present evidence that a subfamily II member of LBD, namely SlLBD40, collaborates with SlMYC2 in the regulation of fruit expansion. Overexpression of SlLBD40 significantly promoted fruit growth by promoting mesocarp cell expansion, while knockout of SlLBD40 showed the opposite result. Similarly, SlMYC2 knockout resulted in a significant decrease in cell expansion within the fruit. Genetic analysis indicated that SlLBD40-mediated cell expansion depends on the expression of SlMYC2. SlLBD40 bound to the promoter of SlEXPA5, an expansin gene, but did not activate its expression directly. While, the co-expression of SlMYC2 and SlLBD40 significantly stimulated the activation of SlEXPA5, leading to an increase in fruit size. SlLBD40 interacted with SlMYC2 and enhanced the stability and abundance of SlMYC2. Furthermore, SlMYC2 directly targeted and activated the expression of SlLBD40, which is essential for SlLBD40-mediated fruit expansion. In summary, our research elucidates the role of the interaction between SlLBD40 and SlMYC2 in promoting cell expansion in tomato fruits, thus providing novel insights into the molecular genetics underlying fruit growth.
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Affiliation(s)
- Lun Liu
- College of Horticulture, China Agricultural University, Beijing, 100193, China
- College of Horticulture, Anhui Agricultural University, Hefei, 230036, China
| | - Jialong Zhang
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Jiayi Xu
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Yafei Li
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Hongmei Lv
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Fei Wang
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Junxin Guo
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Tao Lin
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Bing Zhao
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Xin-Xu Li
- Beijing Cuihu Agritech Co. Ltd., Beijing, 100095, China
| | - Yang-Dong Guo
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Na Zhang
- College of Horticulture, China Agricultural University, Beijing, 100193, China
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Liu H, Yao X, Fan J, Lv L, Zhao Y, Nie J, Guo Y, Zhang L, Huang H, Shi Y, Zhang Q, Li J, Sui X. Cell wall invertase 3 plays critical roles in providing sugars during pollination and fertilization in cucumber. PLANT PHYSIOLOGY 2024; 195:1293-1311. [PMID: 38428987 DOI: 10.1093/plphys/kiae119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/25/2024] [Accepted: 01/31/2024] [Indexed: 03/03/2024]
Abstract
In plants, pollen-pistil interactions during pollination and fertilization mediate pollen hydration and germination, pollen tube growth, and seed set and development. Cell wall invertases (CWINs) help provide the carbohydrates for pollen development; however, their roles in pollination and fertilization have not been well established. In cucumber (Cucumis sativus), CsCWIN3 showed the highest expression in flowers, and we further examined CsCWIN3 for functions during pollination to seed set. Both CsCWIN3 transcript and CsCWIN3 protein exhibited similar expression patterns in the sepals, petals, stamen filaments, anther tapetum, and pollen of male flowers, as well as in the stigma, style, transmitting tract, and ovule funiculus of female flowers. Notably, repression of CsCWIN3 in cucumber did not affect the formation of parthenocarpic fruit but resulted in an arrested growth of stigma integuments in female flowers and a partially delayed dehiscence of anthers with decreased pollen viability in male flowers. Consequently, the pollen tube grew poorly in the gynoecia after pollination. In addition, CsCWIN3-RNA interference plants also showed affected seed development. Considering that sugar transporters could function in cucumber fecundity, we highlight the role of CsCWIN3 and a potential close collaboration between CWIN and sugar transporters in these processes. Overall, we used molecular and physiological analyses to determine the CsCWIN3-mediated metabolism during pollen formation, pollen tube growth, and plant fecundity. CsCWIN3 has essential roles from pollination and fertilization to seed set but not parthenocarpic fruit development in cucumber.
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Affiliation(s)
- Huan Liu
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Xuehui Yao
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Jingwei Fan
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Lijun Lv
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Yalong Zhao
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Jing Nie
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Yicong Guo
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Lidong Zhang
- Tianjin Academy of Agricultural Sciences, Tianjin Kernel Cucumber Research Institute, Tianjin 300192, China
- State Key Laboratory of Vegetable Biobreeding, Ministry of Science and Technology of the People's Republic of China, Tianjin 300192, China
| | - Hongyu Huang
- Tianjin Academy of Agricultural Sciences, Tianjin Kernel Cucumber Research Institute, Tianjin 300192, China
- State Key Laboratory of Vegetable Biobreeding, Ministry of Science and Technology of the People's Republic of China, Tianjin 300192, China
| | - Yuzi Shi
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Qian Zhang
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Jiawang Li
- Tianjin Academy of Agricultural Sciences, Tianjin Kernel Cucumber Research Institute, Tianjin 300192, China
- State Key Laboratory of Vegetable Biobreeding, Ministry of Science and Technology of the People's Republic of China, Tianjin 300192, China
| | - Xiaolei Sui
- Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, College of Horticulture, China Agricultural University, Beijing 100193, China
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Baranov D, Dolgov S, Timerbaev V. New Advances in the Study of Regulation of Tomato Flowering-Related Genes Using Biotechnological Approaches. PLANTS (BASEL, SWITZERLAND) 2024; 13:359. [PMID: 38337892 PMCID: PMC10856997 DOI: 10.3390/plants13030359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/21/2024] [Accepted: 01/24/2024] [Indexed: 02/12/2024]
Abstract
The tomato is a convenient object for studying reproductive processes, which has become a classic. Such complex processes as flowering and fruit setting require an understanding of the fundamental principles of molecular interaction, the structures of genes and proteins, the construction of signaling pathways for transcription regulation, including the synchronous actions of cis-regulatory elements (promoter and enhancer), trans-regulatory elements (transcription factors and regulatory RNAs), and transposable elements and epigenetic regulators (DNA methylation and acetylation, chromatin structure). Here, we discuss the current state of research on tomatoes (2017-2023) devoted to studying the function of genes that regulate flowering and signal regulation systems using genome-editing technologies, RNA interference gene silencing, and gene overexpression, including heterologous expression. Although the central candidate genes for these regulatory components have been identified, a complete picture of their relationship has yet to be formed. Therefore, this review summarizes the latest achievements related to studying the processes of flowering and fruit set. This work attempts to display the gene interaction scheme to better understand the events under consideration.
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Affiliation(s)
- Denis Baranov
- Laboratory of Expression Systems and Plant Genome Modification, Branch of Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 142290 Pushchino, Russia; (D.B.); (S.D.)
- Laboratory of Plant Genetic Engineering, All-Russia Research Institute of Agricultural Biotechnology, 127550 Moscow, Russia
| | - Sergey Dolgov
- Laboratory of Expression Systems and Plant Genome Modification, Branch of Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 142290 Pushchino, Russia; (D.B.); (S.D.)
- Laboratory of Plant Genetic Engineering, All-Russia Research Institute of Agricultural Biotechnology, 127550 Moscow, Russia
| | - Vadim Timerbaev
- Laboratory of Expression Systems and Plant Genome Modification, Branch of Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 142290 Pushchino, Russia; (D.B.); (S.D.)
- Laboratory of Plant Genetic Engineering, All-Russia Research Institute of Agricultural Biotechnology, 127550 Moscow, Russia
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5
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Baranov D, Timerbaev V. Recent Advances in Studying the Regulation of Fruit Ripening in Tomato Using Genetic Engineering Approaches. Int J Mol Sci 2024; 25:760. [PMID: 38255834 PMCID: PMC10815249 DOI: 10.3390/ijms25020760] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 12/28/2023] [Accepted: 01/02/2024] [Indexed: 01/24/2024] Open
Abstract
Tomato (Solanum lycopersicum L.) is one of the most commercially essential vegetable crops cultivated worldwide. In addition to the nutritional value, tomato is an excellent model for studying climacteric fruits' ripening processes. Despite this, the available natural pool of genes that allows expanding phenotypic diversity is limited, and the difficulties of crossing using classical selection methods when stacking traits increase proportionally with each additional feature. Modern methods of the genetic engineering of tomatoes have extensive potential applications, such as enhancing the expression of existing gene(s), integrating artificial and heterologous gene(s), pointing changes in target gene sequences while keeping allelic combinations characteristic of successful commercial varieties, and many others. However, it is necessary to understand the fundamental principles of the gene molecular regulation involved in tomato fruit ripening for its successful use in creating new varieties. Although the candidate genes mediate ripening have been identified, a complete picture of their relationship has yet to be formed. This review summarizes the latest (2017-2023) achievements related to studying the ripening processes of tomato fruits. This work attempts to systematize the results of various research articles and display the interaction pattern of genes regulating the process of tomato fruit ripening.
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Affiliation(s)
- Denis Baranov
- Laboratory of Expression Systems and Plant Genome Modification, Branch of Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, 142290 Pushchino, Russia;
- Laboratory of Plant Genetic Engineering, All-Russia Research Institute of Agricultural Biotechnology, 127550 Moscow, Russia
| | - Vadim Timerbaev
- Laboratory of Expression Systems and Plant Genome Modification, Branch of Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, 142290 Pushchino, Russia;
- Laboratory of Plant Genetic Engineering, All-Russia Research Institute of Agricultural Biotechnology, 127550 Moscow, Russia
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Wu B, Xia Y, Zhang G, Wang Y, Wang J, Ma S, Song Y, Yang Z, Ma L, Niu N. Transcriptomics reveals a core transcriptional network of K-type cytoplasmic male sterility microspore abortion in wheat (Triticum aestivum L.). BMC PLANT BIOLOGY 2023; 23:618. [PMID: 38057735 DOI: 10.1186/s12870-023-04611-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 11/15/2023] [Indexed: 12/08/2023]
Abstract
BACKGROUND Cytoplasmic male sterility (CMS) plays a crucial role in hybrid production. K-type CMS, a cytoplasmic male sterile line of wheat with the cytoplasms of Aegilops kotschyi, is widely used due to its excellent characteristics of agronomic performance, easy maintenance and easy restoration. However, the mechanism of its pollen abortion is not yet clear. RESULTS In this study, wheat K-type CMS MS(KOTS)-90-110 (MS line) and it's fertile near-isogenic line MR (KOTS)-90-110 (MR line) were investigated. Cytological analysis indicated that the anthers of MS line microspore nucleus failed to divide normally into two sperm nucleus and lacked starch in mature pollen grains, and the key abortive period was the uninucleate stage to dinuclear stage. Then, we compared the transcriptome of MS line and MR line anthers at these two stages. 11,360 and 5182 differentially expressed genes (DEGs) were identified between the MS and MR lines in the early uninucleate and binucleate stages, respectively. Based on GO enrichment and KEGG pathways analysis, it was evident that significant transcriptomic differences were "plant hormone signal transduction", "MAPK signaling pathway" and "spliceosome". We identified 17 and 10 DEGs associated with the IAA and ABA signal transduction pathways, respectively. DEGs related to IAA signal transduction pathway were downregulated in the early uninucleate stage of MS line. The expression level of DEGs related to ABA pathway was significantly upregulated in MS line at the binucleate stage compared to MR line. The determination of plant hormone content and qRT-PCR further confirmed that hormone imbalance in MS lines. Meanwhile, 1 and 2 DEGs involved in ABA and Ethylene metabolism were also identified in the MAPK cascade pathway, respectively; the significant up regulation of spliceosome related genes in MS line may be another important factor leading to pollen abortion. CONCLUSIONS We proposed a transcriptome-mediated pollen abortion network for K-type CMS in wheat. The main idea is hormone imbalance may be the primary factor, MAPK cascade pathway and alternative splicing (AS) may also play important regulatory roles in this process. These findings provided intriguing insights for the molecular mechanism of microspore abortion in K-type CMS, and also give useful clues to identify the crucial genes of CMS in wheat.
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Affiliation(s)
- Baolin Wu
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
| | - Yu Xia
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Gaisheng Zhang
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
| | - Yongqing Wang
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
| | - Junwei Wang
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
| | - Shoucai Ma
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
| | - Yulong Song
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
| | - Zhiquan Yang
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China
| | - Lingjian Ma
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China.
| | - Na Niu
- College of Agronomy, Northwest A & F University, Key Laboratory of Crop Heterosis of Shaanxi Province, Wheat Breeding Engineering Research Center, Ministry of Education, Yangling, 712100, Shaanxi, China.
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Gautam R, Shukla P, Kirti PB. Male sterility in plants: an overview of advancements from natural CMS to genetically manipulated systems for hybrid seed production. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2023; 136:195. [PMID: 37606708 DOI: 10.1007/s00122-023-04444-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 08/07/2023] [Indexed: 08/23/2023]
Abstract
KEY MESSAGE The male sterility system in plants has traditionally been utilized for hybrid seed production. In last three decades, genetic manipulation for male sterility has revolutionized this area of research related to hybrid seed production technology. Here, we have surveyed some of the natural cytoplasmic male sterility (CMS) systems that existed/ were developed in different crop plants for developing male sterility-fertility restoration systems used in hybrid seed production and highlighted some of the recent biotechnological advancements in the development of genetically engineered systems that occurred in this area. We have indicated the possible future directions toward the development of engineered male sterility systems. Cytoplasmic male sterility (CMS) is an important trait that is naturally prevalent in many plant species, which has been used in the development of hybrid varieties. This is associated with the use of appropriate genes for fertility restoration provided by the restorer line that restores fertility on the corresponding CMS line. The development of hybrids based on a CMS system has been demonstrated in several different crops. However, there are examples of species, which do not have usable cytoplasmic male sterility and fertility restoration systems (Cytoplasmic Genetic Male Sterility Systems-CGMS) for hybrid variety development. In such plants, it is necessary to develop usable male sterile lines through genetic engineering with the use of heterologous expression of suitable genes that control the development of male gametophyte and fertile male gamete formation. They can also be developed through gene editing using the recently developed CRISPR-Cas technology to knock out suitable genes that are responsible for the development of male gametes. The present review aims at providing an insight into the development of various technologies for successful production of hybrid varieties and is intended to provide only essential information on male sterility systems starting from naturally occurring ones to the genetically engineered systems obtained through different means.
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Affiliation(s)
- Ranjana Gautam
- Department of Life Sciences and Biotechnology, Chhatrapati Shahu Ji Maharaj University, Kanpur, Uttar Pradesh, 208024, India
| | - Pawan Shukla
- Seri-Biotech Research Laboratory, Central Silk Board, Carmelram Post, Kodathi, Bangalore, 560035, India.
| | - P B Kirti
- Agri Biotech Foundation, PJTS Agricultural University Campus, Rajendranagar, Hyderabad, Telangana, 500030, India
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Liu Y, Liu Y, He Y, Yan Y, Yu X, Ali M, Pan C, Lu G. Cytokinin-inducible response regulator SlRR6 controls plant height through gibberellin and auxin pathways in tomato. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:4471-4488. [PMID: 37115725 DOI: 10.1093/jxb/erad159] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 04/27/2023] [Indexed: 06/19/2023]
Abstract
Plant height is a key agronomic trait regulated by several phytohormones such as gibberellins (GAs) and auxin. However, little is known about how cytokinin (CK) participates in this process. Here, we report that SlRR6, a type-A response regulator in the CK signaling pathway, positively regulates plant height in tomato. SlRR6 was induced by exogenous kinetin and GA3, but inhibited by indole-3-acetic acid (IAA). Knock out of SlRR6 reduced tomato plant height through shortening internode length, while overexpression of SlRR6 caused taller plants due to increased internode number. Cytological observation of longitudinal stems showed that both knock out and overexpression of SlRR6 generated larger cells, but significantly reduced cell numbers in each internode. Further studies demonstrated that overexpression of SlRR6 enhanced GA accumulation and lowered IAA content, along with expression changes in GA- and IAA-related genes. Exogenous paclobutrazol and IAA treatments restored the increased plant height phenotype in SlRR6-overexpressing lines. Yeast two-hybrid, bimolecular fluorescence complementation, and co-immunoprecipitation assays showed that SlRR6 interacts with a small auxin up RNA protein, SlSAUR58. Moreover, SlSAUR58-overexpressing plants were dwarf with decreased internode length. Overall, our findings establish SlRR6 as a vital component in the CK signaling, GA, and IAA regulatory network that controls plant height.
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Affiliation(s)
- Yue Liu
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yichen Liu
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yanjun He
- Institute of Vegetable Science, Zhejiang Academy of Agricultural Sciences, Hangzhou 310022, China
| | - Yanqiu Yan
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Xiaolin Yu
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Muhammad Ali
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Changtian Pan
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Gang Lu
- Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agricultural, Zhejiang University, Hangzhou 310058, China
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9
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Lu L, Yang H, Xu Y, Zhang L, Wu J, Yi H. Laser capture microdissection-based spatiotemporal transcriptomes uncover regulatory networks during seed abortion in seedless Ponkan (Citrus reticulata). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 115:642-661. [PMID: 37077034 DOI: 10.1111/tpj.16251] [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: 11/09/2022] [Revised: 04/06/2023] [Accepted: 04/12/2023] [Indexed: 05/03/2023]
Abstract
Seed abortion is an important process in the formation of seedless characteristics in citrus fruits. However, the molecular regulatory mechanism underlying citrus seed abortion is poorly understood. Laser capture microdissection-based RNA-seq combined with Pacbio-seq was used to profile seed development in the Ponkan cultivars 'Huagan No. 4' (seedless Ponkan) (Citrus reticulata) and 'E'gan No. 1' (seeded Ponkan) (C. reticulata) in two types of seed tissue across three developmental stages. Through comparative transcriptome and dynamic phytohormone analyses, plant hormone signal, cell division and nutrient metabolism-related processes were revealed to play critical roles in the seed abortion of 'Huagan No. 4'. Moreover, several genes may play indispensable roles in seed abortion of 'Huagan No. 4', such as CrWRKY74, CrWRKY48 and CrMYB3R4. Overexpression of CrWRKY74 in Arabidopsis resulted in severe seed abortion. By analyzing the downstream regulatory network, we further determined that CrWRKY74 participated in seed abortion regulation by inducing abnormal programmed cell death. Of particular importance is that a preliminary model was proposed to depict the regulatory networks underlying seed abortion in citrus. The results of this study provide novel insights into the molecular mechanism across citrus seed development, and reveal the master role of CrWRKY74 in seed abortion of 'Huagan No. 4'.
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Affiliation(s)
- Liqing Lu
- National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Haijian Yang
- Fruit Tree Research Institute of Chongqing Academy of Agricultural Sciences, Chongqing, 401329, P.R. China
| | - Yanhui Xu
- National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Li Zhang
- National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Juxun Wu
- National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, P.R. China
| | - Hualin Yi
- National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops, Huazhong Agricultural University, Wuhan, 430070, P.R. China
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Driesen E, Saeys W, De Proft M, Lauwers A, Van den Ende W. Far-Red Light Mediated Carbohydrate Concentration Changes in Leaves of Sweet Basil, a Stachyose Translocating Plant. Int J Mol Sci 2023; 24:ijms24098378. [PMID: 37176086 PMCID: PMC10179449 DOI: 10.3390/ijms24098378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/02/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023] Open
Abstract
Photosynthetic active radiation (PAR) refers to photons between 400 and 700 nm. These photons drive photosynthesis, providing carbohydrates for plant metabolism and development. Far-red radiation (FR, 701-750 nm) is excluded in this definition because no FR is absorbed by the plant photosynthetic pigments. However, including FR in the light spectrum provides substantial benefits for biomass production and resource-use efficiency. We investigated the effects of continuous FR addition and end-of-day additional FR to a broad white light spectrum (BW) on carbohydrate concentrations in the top and bottom leaves of sweet basil (Ocimum basilicum L.), a species that produces the raffinose family oligosaccharides raffinose and stachyose and preferentially uses the latter as transport sugar. Glucose, fructose, sucrose, raffinose, and starch concentrations increased significantly in top and bottom leaves with the addition of FR light. The increased carbohydrate pools under FR light treatments are associated with more efficient stachyose production and potentially improved phloem loading through increased sucrose homeostasis in intermediary cells. The combination of a high biomass yield, increased resource-use efficiency, and increased carbohydrate concentration in leaves in response to the addition of FR light offers opportunities for commercial plant production in controlled growth environments.
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Affiliation(s)
- Elisa Driesen
- KU Leuven, Department of Biosystems, Willem De Croylaan 42, 3001 Leuven, Belgium
| | - Wouter Saeys
- KU Leuven, Department of Biosystems, Willem De Croylaan 42, 3001 Leuven, Belgium
| | - Maurice De Proft
- KU Leuven, Department of Biosystems, Willem De Croylaan 42, 3001 Leuven, Belgium
| | | | - Wim Van den Ende
- KU Leuven, Laboratory of Molecular Plant Biology, Kasteelpark Arenberg 31, 3001 Leuven, Belgium
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11
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Xie Y, Hou Z, Shi M, Wang Q, Yang Z, Lim KJ, Wang Z. Transcriptional Regulation of Female and Male Flower Bud Initiation and Development in Pecan ( Carya illinoensis). PLANTS (BASEL, SWITZERLAND) 2023; 12:1378. [PMID: 36987065 PMCID: PMC10051282 DOI: 10.3390/plants12061378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/16/2023] [Accepted: 03/16/2023] [Indexed: 06/19/2023]
Abstract
Pecan (Carya illinoensis) nuts are delicious and rich in unsaturated fatty acids, which are beneficial for human health. Their yield is closely related to several factors, such as the ratio of female and male flowers. We sampled and paraffin-sectioned female and male flower buds for one year and determined the stages of initial flower bud differentiation, floral primordium formation, and pistil and stamen primordium formation. We then performed transcriptome sequencing on these stages. Our data analysis suggested that FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 play a role in flower bud differentiation. J3 was highly expressed in the early stage of female flower buds and may play a role in regulating flower bud differentiation and flowering time. Genes such as NF-YA1 and STM were expressed during male flower bud development. NF-YA1 belongs to the NF-Y transcription factor family and may initiate downstream events leading to floral transformation. STM promoted the transformation of leaf buds to flower buds. AP2 may have been involved in the establishment of floral meristem characteristics and the determination of floral organ characteristics. Our results lay a foundation for the control and subsequent regulation of female and male flower bud differentiation and yield improvement.
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12
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Yang D, Wang Z, Huang X, Xu C. Molecular regulation of tomato male reproductive development. ABIOTECH 2023; 4:72-82. [PMID: 37220538 PMCID: PMC10199995 DOI: 10.1007/s42994-022-00094-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/30/2022] [Indexed: 05/25/2023]
Abstract
The reproductive success of flowering plants, which directly affects crop yield, is sensitive to environmental changes. A thorough understanding of how crop reproductive development adapts to climate changes is vital for ensuring global food security. In addition to being a high-value vegetable crop, tomato is also a model plant used for research on plant reproductive development. Tomato crops are cultivated under highly diverse climatic conditions worldwide. Targeted crosses of hybrid varieties have resulted in increased yields and abiotic stress resistance; however, tomato reproduction, especially male reproductive development, is sensitive to temperature fluctuations, which can lead to aborted male gametophytes, with detrimental effects on fruit set. We herein review the cytological features as well as genetic and molecular pathways influencing tomato male reproductive organ development and responses to abiotic stress. We also compare the shared features among the associated regulatory mechanisms of tomato and other plants. Collectively, this review highlights the opportunities and challenges related to characterizing and exploiting genic male sterility in tomato hybrid breeding programs.
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Affiliation(s)
- Dandan Yang
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101 China
- CAS-JIC Centre of Excellence for Plant and Microbial Science, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Zhao Wang
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Xiaozhen Huang
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101 China
- CAS-JIC Centre of Excellence for Plant and Microbial Science, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
| | - Cao Xu
- State Key Laboratory of Plant Genomics, National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101 China
- CAS-JIC Centre of Excellence for Plant and Microbial Science, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
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13
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Cheng Z, Song W, Zhang X. Genic male and female sterility in vegetable crops. HORTICULTURE RESEARCH 2022; 10:uhac232. [PMID: 36643746 PMCID: PMC9832880 DOI: 10.1093/hr/uhac232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 09/30/2022] [Indexed: 06/17/2023]
Abstract
Vegetable crops are greatly appreciated for their beneficial nutritional and health components. Hybrid seeds are widely used in vegetable crops for advantages such as high yield and improved resistance, which require the participation of male (stamen) and female (pistil) reproductive organs. Male- or female-sterile plants are commonly used for production of hybrid seeds or seedless fruits in vegetables. In this review we will focus on the types of genic male sterility and factors affecting female fertility, summarize typical gene function and research progress related to reproductive organ identity and sporophyte and gametophyte development in vegetable crops [mainly tomato (Solanum lycopersicum) and cucumber (Cucumis sativus)], and discuss the research trends and application perspectives of the sterile trait in vegetable breeding and hybrid production, in order to provide a reference for fertility-related germplasm innovation.
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Affiliation(s)
- Zhihua Cheng
- State Key Laboratories of Agrobiotechnology, Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, MOE Joint Laboratory for International Cooperation in Crop Molecular Breeding, China Agricultural University, Beijing, 100193, China
| | - Weiyuan Song
- State Key Laboratories of Agrobiotechnology, Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, MOE Joint Laboratory for International Cooperation in Crop Molecular Breeding, China Agricultural University, Beijing, 100193, China
| | - Xiaolan Zhang
- State Key Laboratories of Agrobiotechnology, Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops, MOE Joint Laboratory for International Cooperation in Crop Molecular Breeding, China Agricultural University, Beijing, 100193, China
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14
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Comparative Transcriptome Analysis Reveals Hormone Signal Transduction and Sucrose Metabolism Related Genes Involved in the Regulation of Anther Dehiscence in Photo-Thermo-Sensitive Genic Male Sterile Wheat. Biomolecules 2022; 12:biom12081149. [PMID: 36009044 PMCID: PMC9406143 DOI: 10.3390/biom12081149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 01/12/2023] Open
Abstract
Anther dehiscence is an important process to release pollen and then is a critical event in pollination. In the wheat photo-thermo-sensitive genic male sterility (PTGMS) line, pollen cannot release from anther since the anther cannot dehisce during anther dehiscence stage in a sterile condition. In this study, we carried out RNA-sequencing to analyze the transcriptome of one wheat PTGMS line BS366 during anther dehiscence under fertile and sterile conditions to explore the mechanism. We identified 6306 differentially expressed genes (DEGs). Weighted gene co-expression network analysis (WGCNA) and KEGG analysis showed that DEGs were mainly related to “hormone signal transduction pathway” and “starch and sucrose metabolism”. We identified 35 and 23 DEGs related hormone signal transduction and sucrose metabolism, respectively. Compared with conventional wheat Jing411, there were some changes in the contents of hormones, including JA, IAA, BR, ABA and GA3, and sucrose, during three anther dehiscence stages in the sterile condition in BS366. We performed qRT-PCR to verify the expression levels of some critical DEGs of the hormone signaling pathway and the starch and sucrose metabolism pathway. The results showed disparate expression patterns of the critical DEGs of the hormone signaling pathway and the starch and sucrose metabolism pathway in different conditions, suggesting these genes may be involved in the regulation of the anther dehiscence in BS366. Finally, we conducted a hypothesis model to reveal the regulation pathway of hormones and sucrose on anther dehiscence. The information provided new clues to the molecular mechanisms of anther dehiscence in wheat and improved wheat hybrid breeding.
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Zhang Z, Liu Y, Yuan Q, Xiong C, Xu H, Hu B, Suo H, Yang S, Hou X, Yuan F, Pei Z, Dai X, Zou X, Liu F. The bHLH1-DTX35/DFR module regulates pollen fertility by promoting flavonoid biosynthesis in Capsicum annuum L. HORTICULTURE RESEARCH 2022; 9:uhac172. [PMID: 36238346 PMCID: PMC9552195 DOI: 10.1093/hr/uhac172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 07/25/2022] [Indexed: 06/16/2023]
Abstract
High pollen fertility can ensure the yield and efficiency of breeding work, but factors that affect the fertility of pepper pollen have not been studied extensively. In this work, we screened the reduced pollen fertility 1 (rpf1) mutant of Capsicum annuum with reduced pollen fertility and yellow anthers from an EMS (ethyl methanesulfonate)-mutagenized pepper population. Through construction of an F 2 population followed by BSA (bulked segregant analysis) mapping and KASP genotyping, we identified CabHLH1 as a candidate gene for control of this trait. A G → A mutation at a splice acceptor site in CabHLH1 causes a frameshift mutation in the mutant, and the translated protein is terminated prematurely. Previous studies on CabHLH1 have focused on the regulation of flavonoid synthesis. Here, we found that CabHLH1 also has an important effect on pollen fertility. Pollen vigor, anther flavonoid content, and seed number were lower in CabHLH1-silenced pepper plants, whereas anther H2O2 and MDA (malondialdehyde) contents were higher. RNA-seq analyses showed that expression of the flavonoid synthesis genes DFR, ANS, and RT was significantly reduced in anthers of CabHLH1-silenced plants and rpf1 plants, as was the expression of DTX35, a gene related to pollen fertility and flavonoid transport. Yeast one-hybrid and dual-luciferase reporter assays showed that CabHLH1 can directly bind to the promoters of DTX35 and DFR and activate their expression. These results indicate that CabHLH1 regulates reactive oxygen species homeostasis by promoting the synthesis of anther flavonoids and acts as a positive regulator of pepper pollen fertility.
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Affiliation(s)
| | | | - Qiaoling Yuan
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Cheng Xiong
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Hao Xu
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Bowen Hu
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Huan Suo
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Sha Yang
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Xilin Hou
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Fang Yuan
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Zhenming Pei
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Xiongze Dai
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
| | - Xuexiao Zou
- Engineering Research Center of Education Ministry for Germplasm Innovation and Breeding New Varieties of Horticultural Crops, Key Laboratory for Vegetable Biology of Hunan Province, College of Horticulture, Hunan Agricultural University, Changsha 410125, China
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Wang J, Li M, Zhuo S, Liu Y, Yu X, Mukhtar S, Ali M, Lu G. Mitogen-activated protein kinase 4 is obligatory for late pollen and early fruit development in tomato. HORTICULTURE RESEARCH 2022; 9:uhac048. [PMID: 35591931 PMCID: PMC9113226 DOI: 10.1093/hr/uhac048] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/14/2022] [Indexed: 06/09/2023]
Abstract
Mitogen-activated protein kinase (MAPK) cascades are universal signal transduction modules regulating vegetative and reproductive development of plants. However, the molecular mechanisms of the SlMPK4 gene in tomato pollen and fruit development remain elusive. SlMPK4 is preferentially and highly expressed in tomato stamens and its mRNA levels increase during early flower development, peaking at the mature pollen stage. Either up- or downregulation of SlMPK4 expression had no significant effect on tomato vegetative growth. However, RNAi-mediated suppression of SlMPK4 caused defects in pollen development, resulting in pollen abortion. The aborted pollen grains were either malformed or collapsed and completely lacked viability, resulting in a predominantly reduced fruit set rate in RNAi lines compared with control and overexpressing transgenic plants. Interestingly, seed development was inhibited in RNAi lines. Moreover, >12% of emasculated RNAi flowers developed seedless fruits without pollination. Anthers can produce typical microspore mother cells as well as uninucleate microspores, according to cytological investigations, while binucleate pollen ceased to produce typical mature pollen. Pollen abortion was further confirmed by transmission electron microscopy analysis at the binucleate stage in RNAi plants. The exine layer in aberrant pollen had a normal structure, while the intine layer appeared thicker. Suppression of SlMPK4 affects the transcript level of genes related to cell wall formation and modification, cell signal transduction, and metabolic and biosynthetic processes. A subset of genes that may be putative substrates of plant MAPKs were also differentially changed in RNAi transgenic flowers. Taken together, these results suggest that SlMPK4 plays a critical role in regulating pollen development and fruit development in tomato plants.
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Affiliation(s)
- Jie Wang
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
- Ningbo Academy of Agricultural Sciences, Ningbo 315000, Zhejiang, China
| | - Mengzhuo Li
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
| | - Shibin Zhuo
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
| | - Yue Liu
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
| | - Xiaolin Yu
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
| | - Sidra Mukhtar
- Directorate of Agriculture Research, Agricultural Research Institute Tarnab, Peshawar, Pakistan
| | - Muhammad Ali
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
| | - Gang Lu
- Department of Horticulture, Zhejiang University, Hangzhou 310058, China
- Key Laboratory of Horticultural Plant Growth, Development and Quality Improvement, Ministry of Agricultural, Zhejiang University, Hangzhou 310058, China
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