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Yan G, Li S, Ma M, Quan C, Tian X, Tu J, Shen J, Yi B, Fu T, Ma C, Guo L, Dai C. The transcription factor BnaWRKY10 regulates cytokinin dehydrogenase BnaCKX2 to control cytokinin distribution and seed size in Brassica napus. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:4994-5013. [PMID: 37246599 DOI: 10.1093/jxb/erad201] [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: 03/28/2023] [Accepted: 05/25/2023] [Indexed: 05/30/2023]
Abstract
Cytokinins (CKs) are phytohormones that promote cell division and differentiation. However, the regulation of CK distribution and homeostasis in Brassica napus is poorly understood. Here, the endogenous CKs were first quantified by LC-ESI-MS/MS in rapeseed tissues and visualized by TCSn::GUS reporter lines. Interestingly, the cytokinin oxidase/dehydrogenase BnaCKX2 homologs were mainly expressed in reproductive organs. Subsequently, the quadruple mutants of the four BnaCKX2 homologs were generated. Endogenous CKs were increased in the seeds of the BnaCKX2 quadruple mutants, resulting in a significantly reduced seed size. In contrast, overexpression of BnaA9.CKX2 resulted in larger seeds, probably by delaying endosperm cellularization. Furthermore, the transcription factor BnaC6.WRKY10b, but not BnaC6.WRKY10a, positively regulated BnaA9.CKX2 expression by binding directly to its promoter region. Overexpression of BnaC6.WRKY10b rather than BnaC6.WRKY10a resulted in lower concentration of CKs and larger seeds by activating BnaA9.CKX2 expression, indicating that the functional differentiation of BnaWRKY10 homologs might have occurred during B. napus evolution or domestication. Notably, the haploid types of BnaA9.CKX2 were associated with 1000-seed weight in the natural B. napus population. Overall, the study reveals the distribution of CKs in B. napus tissues, and shows that BnaWRKY10-mediated BnaCKX2 expression is essential for seed size regulation, providing promising targets for oil crop improvement.
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Affiliation(s)
- Guanbo Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Sijia Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Mengya Ma
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Chengtao Quan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Xia Tian
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Jinxing Tu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Jinxiong Shen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Bin Yi
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Tingdong Fu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Chaozhi Ma
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Liang Guo
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Cheng Dai
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
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Qiu Q, Tian X, Wu G, Wu J, Fan X, Yuan D. Comparative analysis of the transcriptome during single-seed formation of Castanea henryi: regulation of starch metabolism and endogenous hormones. BMC PLANT BIOLOGY 2023; 23:90. [PMID: 36782110 PMCID: PMC9926639 DOI: 10.1186/s12870-023-04102-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND In seed plants, the ovule is the precursor to the seed. The process of ovule development and differentiation is regulated by multiple factors, including starch metabolism and endogenous hormones. Castanea henryi produces nuts with high nutritional value. However, the high proportion of empty buds restricts the commercial use of the tree. Previous studies have shown that the empty bud phenotype is closely related to ovule abortion. If none of the ovules in the ovary expand rapidly and develop in 7-8 weeks after pollination, an empty bud will form. Therefore, we studied the development and molecular mechanisms underlying single seed formation in C. henryi. RESULTS We found that 49 days after pollination (DAP) is a critical period for the formation of fertile and abortive ovules. The morphology and starch distribution of the fertile and abortive ovules differed significantly at 49 DAP. The fertile ovules were smooth and round in appearance, with a large amount of starch. In contrast, abortive ovules were smaller with only a small amount of starch. The embryo sac of the abortive ovule proceeded to develop abnormally, and the entire ovule lacked starch. We identified 37 candidate genes involved in metabolism with potential roles in the regulation of starch levels. Three ADP-glucose pyrophosphorylase (AGPase) genes, one granule-bound starch synthase (GBSS) gene, and two beta-amylase genes could affect starch accumulation. The levels of auxin, cytokinins, gibberellins, and jasmonic acid in fertile ovules were higher than those in abortive ovules. In addition, the levels of endogenous abscisic acid and salicylic acid in abortive ovules were higher than those in fertile ovules of the same age, consistent with the expression patterns of genes related to the synthesis of abscisic and salicylic acid and signal transduction. We identified and mapped the differentially expressed genes associated with hormone synthesis and signal transduction. CONCLUSIONS These results improve our general understanding of the molecular mechanisms underlying single seed development in C. henryi and the phenomenon of empty buds, providing directions for future research.
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Affiliation(s)
- Qi Qiu
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China
- Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China
| | | | - Guolong Wu
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China
- Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China
| | - Juntao Wu
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China
- Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China
| | - Xiaoming Fan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China.
- Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China.
| | - Deyi Yuan
- Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Changsha, 410004, China.
- Key Lab of Non-Wood Forest Products of State Forestry Administration, Central South University of Forestry and Technology, Changsha, 410004, China.
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Zhang J, Pai Q, Yue L, Wu X, Liu H, Wang W. Cytokinin regulates female gametophyte development by cell cycle modulation in Arabidopsis thaliana. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 324:111419. [PMID: 35995110 DOI: 10.1016/j.plantsci.2022.111419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/09/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
Male and female gametophyte development, double fertilization, and embryogenesis are key to alternating generations in angiosperms. The female gametophyte of Arabidopsis is an eight-nucleate haploid structure developed from functional megaspores (FMs) through three flawless mitoses regulated by a series of cell cycle genes. Cytokinin, an important phytohormone, plays a critical role in the regulation of plant growth and development. However, the mechanisms by which cytokinins regulate female gametophyte development remain largely unknown. In this study, we constructed transgenic plants (pES1::CKX1) with low cytokinin levels in the embryo sac. Phenotypic analysis showed that pES1::CKX1 inhibits female gametophyte development. Microscopic observation revealed that female gametophyte development of pES1::CKX1 was delayed. The promoters of all cell cycle genes were cloned and transformed into wild-type (WT). We crossed these transgenic plants of cell cycle genes expressed in ovules with pES1::CKX1 and compared the expression level of β-glucuronidase (GUS) in pES1::CKX1 and WT. Many cell cycle-regulated genes were up or downregulated in pES1::CKX1 compared with WT, and the embryo sac development cell cycle in cycd2;1/+ cycd3;3 was defective. Our results demonstrated that cytokinin affects cell division in the female gametophyte by affecting the expression of cell cycle genes.
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Affiliation(s)
- Jinghua Zhang
- National Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China
| | - Qiaofeng Pai
- National Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China
| | - Ling Yue
- National Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China
| | - Xiaolin Wu
- National Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China
| | - Hui Liu
- National Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China.
| | - Wei Wang
- National Key Laboratory of Wheat and Maize Crop Science, College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, China.
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Huo R, Liu Z, Yu X, Li Z. The Interaction Network and Signaling Specificity of Two-Component System in Arabidopsis. Int J Mol Sci 2020; 21:ijms21144898. [PMID: 32664520 PMCID: PMC7402358 DOI: 10.3390/ijms21144898] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 01/25/2023] Open
Abstract
Two-component systems (TCS) in plants have evolved into a more complicated multi-step phosphorelay (MSP) pathway, which employs histidine kinases (HKs), histidine-containing phosphotransfer proteins (HPts), and response regulators (RRs) to regulate various aspects of plant growth and development. How plants perceive the external signals, then integrate and transduce the secondary signals specifically to the desired destination, is a fundamental characteristic of the MSP signaling network. The TCS elements involved in the MSP pathway and molecular mechanisms of signal transduction have been best understood in the model plant Arabidopsis thaliana. In this review, we focus on updated knowledge on TCS signal transduction in Arabidopsis. We first present a brief description of the TCS elements; then, the protein–protein interaction network is established. Finally, we discuss the possible molecular mechanisms involved in the specificity of the MSP signaling at the mRNA and protein levels.
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Affiliation(s)
- Ruxue Huo
- Institute of Integrative Plant Biology, Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China;
- College of Agriculture and Forestry Sciences, Linyi University, Linyi 276000, China
| | - Zhenning Liu
- College of Agriculture and Forestry Sciences, Linyi University, Linyi 276000, China
- Correspondence: (Z.L.); (Z.L.)
| | - Xiaolin Yu
- College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China;
| | - Zongyun Li
- Institute of Integrative Plant Biology, Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China;
- Correspondence: (Z.L.); (Z.L.)
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Cerbantez-Bueno VE, Zúñiga-Mayo VM, Reyes-Olalde JI, Lozano-Sotomayor P, Herrera-Ubaldo H, Marsch-Martinez N, de Folter S. Redundant and Non-redundant Functions of the AHK Cytokinin Receptors During Gynoecium Development. FRONTIERS IN PLANT SCIENCE 2020; 11:568277. [PMID: 33117412 PMCID: PMC7575793 DOI: 10.3389/fpls.2020.568277] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/17/2020] [Indexed: 05/17/2023]
Abstract
The phytohormone cytokinin is crucial for plant growth and development. The site of action of cytokinin in the plant is dependent on the expression of the cytokinin receptors. In Arabidopsis, there are three cytokinin receptors that present some overlap in expression pattern. Functional studies demonstrated that the receptors play highly redundant roles but also have specialized functions. Here, we focus on gynoecium development, which is the female reproductive part of the plant. Cytokinin signaling has been demonstrated to be important for reproductive development, positively affecting seed yield and fruit production. Most of these developmental processes are regulated by cytokinin during early gynoecium development. While some information is available, there is a gap in knowledge on cytokinin function and especially on the cytokinin receptors during early gynoecium development. Therefore, we studied the expression patterns and the role of the cytokinin receptors during gynoecium development. We found that the three receptors are expressed in the gynoecium and that they have redundant and specialized functions.
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Affiliation(s)
- Vincent E. Cerbantez-Bueno
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - Victor M. Zúñiga-Mayo
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - J. Irepan Reyes-Olalde
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - Paulina Lozano-Sotomayor
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | - Humberto Herrera-Ubaldo
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
| | | | - Stefan de Folter
- Unidad de Genómica Avanzada (UGA-LANGEBIO), Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Irapuato, Mexico
- *Correspondence: Stefan de Folter,
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Xu G, Huang J, Lei SK, Sun XG, Li X. Comparative gene expression profile analysis of ovules provides insights into Jatropha curcas L. ovule development. Sci Rep 2019; 9:15973. [PMID: 31685957 PMCID: PMC6828956 DOI: 10.1038/s41598-019-52421-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 10/03/2019] [Indexed: 02/02/2023] Open
Abstract
Jatropha curcas, an economically important biofuel feedstock with oil-rich seeds, has attracted considerable attention among researchers in recent years. Nevertheless, valuable information on the yield component of this plant, particularly regarding ovule development, remains scarce. In this study, transcriptome profiles of anther and ovule development were established to investigate the ovule development mechanism of J. curcas. In total, 64,325 unigenes with annotation were obtained, and 1723 differentially expressed genes (DEGs) were identified between different stages. The DEG analysis showed the participation of five transcription factor families (bHLH, WRKY, MYB, NAC and ERF), five hormone signaling pathways (auxin, gibberellic acid (GA), cytokinin, brassinosteroids (BR) and jasmonic acid (JA)), five MADS-box genes (AGAMOUS-2, AGAMOUS-1, AGL1, AGL11, and AGL14), SUP and SLK3 in ovule development. The role of GA and JA in ovule development was evident with increases in flower buds during ovule development: GA was increased approximately twofold, and JA was increased approximately sevenfold. In addition, the expression pattern analysis using qRT-PCR revealed that CRABS CLAW and AGAMOUS-2 were also involved in ovule development. The upregulation of BR signaling genes during ovule development might have been regulated by other phytohormone signaling pathways through crosstalk. This study provides a valuable framework for investigating the regulatory networks of ovule development in J. curcas.
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Affiliation(s)
- Gang Xu
- Institute for Forest Resources and Environment of Guizhou / College of Forestry, Guizhou University, Guiyang, 550025, P.R. China. .,Institute of Entomology, Guizhou University, Guiyang, Guizhou, P.R. China.
| | - Jian Huang
- Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for Research and Development of Fine Chemicals of Guizhou University, Guiyang, Guizhou, P.R. China
| | - Shi-Kang Lei
- School of Life Science, Guizhou University, Guiyang, Guizhou, P.R. China
| | - Xue-Guang Sun
- Institute for Forest Resources and Environment of Guizhou / College of Forestry, Guizhou University, Guiyang, 550025, P.R. China
| | - Xue Li
- School of Life Science, Guizhou University, Guiyang, Guizhou, P.R. China
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Hodgens C, Nimchuk ZL, Kieber JJ. indCAPS: A tool for designing screening primers for CRISPR/Cas9 mutagenesis events. PLoS One 2017; 12:e0188406. [PMID: 29141013 PMCID: PMC5687723 DOI: 10.1371/journal.pone.0188406] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/06/2017] [Indexed: 11/25/2022] Open
Abstract
Genetic manipulation of organisms using CRISPR/Cas9 technology generally produces small insertions/deletions (indels) that can be difficult to detect. Here, we describe a technique to easily and rapidly identify such indels. Sequence-identified mutations that alter a restriction enzyme recognition site can be readily distinguished from wild-type alleles using a cleaved amplified polymorphic sequence (CAPS) technique. If a restriction site is created or altered by the mutation such that only one allele contains the restriction site, a polymerase chain reaction (PCR) followed by a restriction digest can be used to distinguish the two alleles. However, in the case of most CRISPR-induced alleles, no such restriction sites are present in the target sequences. In this case, a derived CAPS (dCAPS) approach can be used in which mismatches are purposefully introduced in the oligonucleotide primers to create a restriction site in one, but not both, of the amplified templates. Web-based tools exist to aid dCAPS primer design, but when supplied sequences that include indels, the current tools often fail to suggest appropriate primers. Here, we report the development of a Python-based, species-agnostic web tool, called indCAPS, suitable for the design of PCR primers used in dCAPS assays that is compatible with indels. This tool should have wide utility for screening editing events following CRISPR/Cas9 mutagenesis as well as for identifying specific editing events in a pool of CRISPR-mediated mutagenesis events. This tool was field-tested in a CRISPR mutagenesis experiment targeting a cytokinin receptor (AHK3) in Arabidopsis thaliana. The tool suggested primers that successfully distinguished between wild-type and edited alleles of a target locus and facilitated the isolation of two novel ahk3 null alleles. Users can access indCAPS and design PCR primers to employ dCAPS to identify CRISPR/Cas9 alleles at http://indcaps.kieber.cloudapps.unc.edu/.
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Affiliation(s)
- Charles Hodgens
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Zachary L. Nimchuk
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Joseph J. Kieber
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Müller CJ, Larsson E, Spíchal L, Sundberg E. Cytokinin-Auxin Crosstalk in the Gynoecial Primordium Ensures Correct Domain Patterning. PLANT PHYSIOLOGY 2017; 175:1144-1157. [PMID: 28894023 PMCID: PMC5664465 DOI: 10.1104/pp.17.00805] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/05/2017] [Indexed: 05/23/2023]
Abstract
The Arabidopsis (Arabidopsis thaliana) gynoecium consists of two congenitally fused carpels made up of two lateral valve domains and two medial domains, which retain meristematic properties and later fuse to produce the female reproductive structures vital for fertilization. Polar auxin transport (PAT) is important for setting up distinct apical auxin signaling domains in the early floral meristem remnants allowing for lateral domain identity and outgrowth. Crosstalk between auxin and cytokinin plays an important role in the development of other meristematic tissues, but hormone interaction studies to date have focused on more accessible later-stage gynoecia and the spatiotemporal interactions pivotal for patterning of early gynoecium primordia remain unknown. Focusing on the earliest stages, we propose a cytokinin-auxin feedback model during early gynoecium patterning and hormone homeostasis. Our results suggest that cytokinin positively regulates auxin signaling in the incipient gynoecial primordium and strengthen the concept that cytokinin regulates auxin homeostasis during gynoecium development. Specifically, medial cytokinin promotes auxin biosynthesis components [YUCCA1/4 (YUC1/4)] in, and PINFORMED7 (PIN7)-mediated auxin efflux from, the medial domain. The resulting laterally focused auxin signaling triggers ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN6 (AHP6), which then represses cytokinin signaling in a PAT-dependent feedback. Cytokinin also down-regulates PIN3, promoting auxin accumulation in the apex. The yuc1, yuc4, and ahp6 mutants are hypersensitive to exogenous cytokinin and 1-napthylphthalamic acid (NPA), highlighting their role in mediolateral gynoecium patterning. In summary, these mechanisms self-regulate cytokinin and auxin signaling domains, ensuring correct domain specification and gynoecium development.
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Affiliation(s)
- Christina Joy Müller
- Department of Plant Biology, Swedish University of Agricultural Sciences, Uppsala BioCenter and Linnean Centre for Plant Biology in Uppsala, 75007 Uppsala, Sweden
| | - Emma Larsson
- Department of Plant Biology, Swedish University of Agricultural Sciences, Uppsala BioCenter and Linnean Centre for Plant Biology in Uppsala, 75007 Uppsala, Sweden
| | - Lukáš Spíchal
- Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Olomouc, CZ-78371, Czech Republic
| | - Eva Sundberg
- Department of Plant Biology, Swedish University of Agricultural Sciences, Uppsala BioCenter and Linnean Centre for Plant Biology in Uppsala, 75007 Uppsala, Sweden
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Liu B, De Storme N, Geelen D. Cold interferes with male meiotic cytokinesis in Arabidopsis thaliana independently of the AHK2/3-AHP2/3/5 cytokinin signaling module. Cell Biol Int 2017; 41:879-889. [PMID: 28618065 DOI: 10.1002/cbin.10805] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 06/11/2017] [Indexed: 12/21/2022]
Abstract
Previously we have shown that low temperature stress in Arabidopsis causes defects in microtubule organization and cytokinesis in male meiocytes, which leads to the formation of diploid pollen. Because cytokinin (CK) mediates multiple physiological responses to cold stress, we investigated whether CK signaling is involved in cold-induced diploid pollen formation. To this end, we monitored male sporogenesis in a series of mutants defective in CK metabolism and signalling. Arabidopsis plants with altered CK homeostasis, that is, the ahk2-2 ahk3-3 double and the ahp2-1 ahp3 ahp5-2 triple mutant, were cold sensitive and displayed similar defective male meiotic cytokinesis as wild type plants upon cold stress. These findings demonstrate that the AHK2/3-AHP2/3/5 CK-signaling module is not required for cold-induced ploidy stability of male gamete in Arabidopsis. Cytological analysis further revealed that the cold-induced cytokinesis defects in the ahk2-2 ahk3-3 mutant correlated with irregular organization of the radial microtubule array (RMA) in tetrad microspores at the end of male meiosis. Contrary to the ahk and ahp mutants, Arabidopsis plants defective for ARR1, a downstream target of ahk and ahp mediated CK signalling, displayed higher cold-tolerance of male meiotic cytokinesis program. We here suggest that the transcription regulator ARR1 may act independently from the CK AHK2/3-AHP2/3/5 signaling module in conveying the cold response to male meiocytes.
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Affiliation(s)
- Bing Liu
- Faculty of Bioscience Engineering, Department of Plant Production, University of Ghent, Ghent, 9000, Belgium
| | - Nico De Storme
- Faculty of Bioscience Engineering, Department of Plant Production, University of Ghent, Ghent, 9000, Belgium
| | - Danny Geelen
- Faculty of Bioscience Engineering, Department of Plant Production, University of Ghent, Ghent, 9000, Belgium
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Cross-Talk Between Sporophyte and Gametophyte Generations Is Promoted by CHD3 Chromatin Remodelers in Arabidopsis thaliana. Genetics 2016; 203:817-29. [PMID: 27075727 DOI: 10.1534/genetics.115.180141] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 03/27/2016] [Indexed: 11/18/2022] Open
Abstract
Angiosperm reproduction requires the integrated development of multiple tissues with different genotypes. To achieve successful fertilization, the haploid female gametophytes and diploid ovary must coordinate their development, after which the male gametes must navigate through the maternal sporophytic tissues to reach the female gametes. After fertilization, seed development requires coordinated development of the maternal diploid integuments, the triploid endosperm, and the diploid zygote. Transcription and signaling factors contribute to communication between these tissues, and roles for epigenetic regulation have been described for some of these processes. Here we identify a broad role for CHD3 chromatin remodelers in Arabidopsis thaliana reproductive development. Plants lacking the CHD3 remodeler, PICKLE, exhibit various reproductive defects including abnormal development of the integuments, female gametophyte, and pollen tube, as well as delayed progression of ovule and embryo development. Genetic analyses demonstrate that these phenotypes result from loss of PICKLE in the maternal sporophyte. The paralogous gene PICKLE RELATED 2 is preferentially expressed in the endosperm and acts antagonistically with respect to PICKLE in the seed: loss of PICKLE RELATED 2 suppresses the large seed phenotype of pickle seeds. Surprisingly, the alteration of seed size in pickle plants is sufficient to determine the expression of embryonic traits in the seedling primary root. These findings establish an important role for CHD3 remodelers in plant reproduction and highlight how the epigenetic status of one tissue can impact the development of genetically distinct tissues.
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Shanks CM, Rice JH, Zubo Y, Schaller GE, Hewezi T, Kieber JJ. The Role of Cytokinin During Infection of Arabidopsis thaliana by the Cyst Nematode Heterodera schachtii. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2016; 29:57-68. [PMID: 26479273 DOI: 10.1094/mpmi-07-15-0156-r] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Plant-parasitic cyst nematodes induce the formation of hypermetabolic feeding sites, termed syncytia, as their sole source of nutrients. The formation of the syncytium is orchestrated by the nematode, in part, by modulation of phytohormone responses, including cytokinin. In response to infection by the nematode Heterodera schachtii, cytokinin signaling is transiently induced at the site of infection and in the developing syncytium. Arabidopsis lines with reduced cytokinin sensitivity show reduced susceptibility to nematode infection, indicating that cytokinin signaling is required for optimal nematode development. Furthermore, lines with increased cytokinin sensitivity also exhibit reduced nematode susceptibility. To ascertain why cytokinin hypersensitivity reduces nematode parasitism, we examined the transcriptomes in wild type and a cytokinin-hypersensitive type-A arr Arabidopsis mutant in response to H. schachtii infection. Genes involved in the response to biotic stress and defense response were elevated in the type-A arr mutant in the absence of nematodes and were hyperinduced following H. schachtii infection, which suggests that the Arabidopsis type-A arr mutants impede nematode development because they are primed to respond to pathogen infection. These results suggest that cytokinin signaling is required for optimal H. schachtii parasitism of Arabidopsis but that elevated cytokinin signaling triggers a heightened immune response to nematode infection.
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Affiliation(s)
- Carly M Shanks
- 1 Department of Biology, University of North Carolina, Chapel Hill, NC 27599, U.S.A
| | - J Hollis Rice
- 2 Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996, U.S.A
| | - Yan Zubo
- 3 Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, U.S.A
| | - G Eric Schaller
- 3 Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, U.S.A
| | - Tarek Hewezi
- 2 Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996, U.S.A
| | - Joseph J Kieber
- 1 Department of Biology, University of North Carolina, Chapel Hill, NC 27599, U.S.A
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