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Gao Y, Li J, He J, Yu Y, Qian Z, Geng Z, Yang L, Zhang Y, Ke Y, Lin Q, Wang J, Chen S, Chen F, Yuan YW, Ding B. BLADE-ON-PETIOLE interacts with CYCLOIDEA to fine-tune CYCLOIDEA-mediated flower symmetry in monkeyflowers ( Mimulus). SCIENCE ADVANCES 2024; 10:eado4571. [PMID: 39141743 PMCID: PMC11323955 DOI: 10.1126/sciadv.ado4571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 07/08/2024] [Indexed: 08/16/2024]
Abstract
Morphological novelties, or key innovations, are instrumental to the diversification of the organisms. In plants, one such innovation is the evolution of zygomorphic flowers, which is thought to promote outcrossing and increase flower morphological diversity. We isolated three allelic mutants from two Mimulus species displaying altered floral symmetry and identified the causal gene as the ortholog of Arabidopsis BLADE-ON-PETIOLE. We found that MlBOP and MlCYC2A physically interact and this BOP-CYC interaction module is highly conserved across the angiosperms. Furthermore, MlBOP self-ubiquitinates and suppresses MlCYC2A self-activation. MlCYC2A, in turn, impedes MlBOP ubiquitination. Thus, this molecular tug-of-war between MlBOP and MlCYC2A fine-tunes the expression of MlCYC2A, contributing to the formation of bilateral symmetry in flowers, a key trait in angiosperm evolution.
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Affiliation(s)
- Yuan Gao
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Jingjian Li
- College of Pharmacy, Guilin Medical University, Guilin 541199, P. R. China
| | - Jiayue He
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Yaqi Yu
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Zexin Qian
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Zhiqiang Geng
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Liuhui Yang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Yumin Zhang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Yujie Ke
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Qiaoshan Lin
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
| | - Jing Wang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
| | - Sumei Chen
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing 210014, P. R. China
| | - Fadi Chen
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing 210014, P. R. China
| | - Yao-Wu Yuan
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, USA
| | - Baoqing Ding
- State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization; Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs; Key Laboratory of State Forestry and Grassland Administration on Biology of Ornamental Plants in East China; College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA
- Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing 210014, P. R. China
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Yang X, Wang Y, Liu TX, Liu Q, Liu J, Lü TF, Yang RX, Guo FX, Wang YZ. CYCLOIDEA-like genes control floral symmetry, floral orientation, and nectar guide patterning. THE PLANT CELL 2023; 35:2799-2820. [PMID: 37132634 PMCID: PMC10396386 DOI: 10.1093/plcell/koad115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 05/04/2023]
Abstract
Actinomorphic flowers usually orient vertically (relative to the horizon) and possess symmetric nectar guides, while zygomorphic flowers often face horizontally and have asymmetric nectar guides, indicating that floral symmetry, floral orientation, and nectar guide patterning are correlated. The origin of floral zygomorphy is dependent on the dorsoventrally asymmetric expression of CYCLOIDEA (CYC)-like genes. However, how horizontal orientation and asymmetric nectar guides are achieved remains poorly understood. Here, we selected Chirita pumila (Gesneriaceae) as a model plant to explore the molecular bases for these traits. By analyzing gene expression patterns, protein-DNA and protein-protein interactions, and encoded protein functions, we identified multiple roles and functional divergence of 2 CYC-like genes, i.e. CpCYC1 and CpCYC2, in controlling floral symmetry, floral orientation, and nectar guide patterning. CpCYC1 positively regulates its own expression, whereas CpCYC2 does not regulate itself. In addition, CpCYC2 upregulates CpCYC1, while CpCYC1 downregulates CpCYC2. This asymmetric auto-regulation and cross-regulation mechanism might explain the high expression levels of only 1 of these genes. We show that CpCYC1 and CpCYC2 determine asymmetric nectar guide formation, likely by directly repressing the flavonoid synthesis-related gene CpF3'5'H. We further suggest that CYC-like genes play multiple conserved roles in Gesneriaceae. These findings shed light on the repeated origins of zygomorphic flowers in angiosperms.
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Affiliation(s)
- Xia Yang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
| | - Yang Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tian-Xia Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qi Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jing Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
| | - Tian-Feng Lü
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
| | - Rui-Xue Yang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Feng-Xian Guo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yin-Zheng Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- China National Botanical Garden, Beijing 100093, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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Poulin V, Amesefe D, Gonzalez E, Alexandre H, Joly S. Testing candidate genes linked to corolla shape variation of a pollinator shift in Rhytidophyllum (Gesneriaceae). PLoS One 2022; 17:e0267540. [PMID: 35853078 PMCID: PMC9295946 DOI: 10.1371/journal.pone.0267540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 04/12/2022] [Indexed: 11/18/2022] Open
Abstract
Floral adaptations to specific pollinators like corolla shape variation often result in reproductive isolation and thus speciation. But despite their ecological importance, the genetic bases of corolla shape transitions are still poorly understood, especially outside model species. Hence, our goal was to identify candidate genes potentially involved in corolla shape variation between two closely related species of the Rhytidophyllum genus (Gesneriaceae family) from the Antilles with contrasting pollination strategies. Rhytidophyllum rupincola has a tubular corolla and is strictly pollinated by hummingbirds, whereas R. auriculatum has more open flowers and is pollinated by hummingbirds, bats, and insects. We surveyed the literature and used a comparative transcriptome sequence analysis of synonymous and non-synonymous nucleotide substitutions to obtain a list of genes that could explain floral variation between R. auriculatum and R. rupincola. We then tested their association with corolla shape variation using QTL mapping in a F2 hybrid population. Out of 28 genes tested, three were found to be good candidates because of a strong association with corolla shape: RADIALIS, GLOBOSA, and JAGGED. Although the role of these genes in Rhytidophyllum corolla shape variation remains to be confirmed, these findings are a first step towards identifying the genes that have been under selection by pollinators and thus involved in reproductive isolation and speciation in this genus.
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Affiliation(s)
- Valérie Poulin
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, Canada
| | - Delase Amesefe
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, Canada
| | - Emmanuel Gonzalez
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, Canada
- Department of Human Genetics, Canadian Centre for Computational Genomics (C3G), McGill University, Montréal, QC, Canada
- Microbiome Research Platform, McGill Interdisciplinary Initiative in Infection and Immunity (MI4), Genome Centre, McGill University, Montréal, QC, Canada
| | - Hermine Alexandre
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, Canada
| | - Simon Joly
- Département de Sciences Biologiques, Institut de Recherche en Biologie Végétale, Université de Montréal, Montréal, Canada
- Montreal Botanical Garden, Montréal, Canada
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Tong J, Knox EB, Morden CW, Cellinese N, Mossolem F, Zubair AS, Howarth DG. Duplication and expression patterns of CYCLOIDEA-like genes in Campanulaceae. EvoDevo 2022; 13:5. [PMID: 35125117 PMCID: PMC8819851 DOI: 10.1186/s13227-021-00189-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 12/22/2021] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
CYCLOIDEA (CYC)-like transcription factors pattern floral symmetry in most angiosperms. In core eudicots, two duplications led to three clades of CYC-like genes: CYC1, CYC2, and CYC3, with orthologs of the CYC2 clade restricting expression dorsally in bilaterally symmetrical flowers. Limited data from CYC3 suggest that they also play a role in flower symmetry in some asterids. We examine the evolution of these genes in Campanulaceae, a group that contains broad transitions between radial and bilateral floral symmetry and 180° resupination (turning upside-down by twisting pedicle).
Results
We identify here all three paralogous CYC-like clades across Campanulaceae. Similar to other core eudicots, we show that CamCYC2 duplicated near the time of the divergence of the bilaterally symmetrical and resupinate Lobelioideae. However, in non-resupinate, bilaterally symmetrical Cyphioideae, CamCYC2 appears to have been lost and CamCYC3 duplicated, suggesting a novel genetic basis for bilateral symmetry in Cyphioideae. We additionally, utilized qRT-PCR to examine the correlation between CYC-like gene expression and shifts in flower morphology in four species of Lobelioideae. As expected, CamCYC2 gene expression was dorsoventrally restricted in bilateral symmetrical flowers. However, because Lobelioideae have resupinate flowers, both CamCYC2A and CamCYC2B are highly expressed in the finally positioned ventral petal lobes, corresponding to the adaxial side of the flower relative to meristem orientation.
Conclusions
Our sequences across Campanulaceae of all three of these paralogous groups suggests that radially symmetrical Campanuloideae duplicated CYC1, Lobelioideae duplicated CYC2 and lost CYC3 early in their divergence, and that Cyphioideae lost CYC2 and duplicated CYC3. This suggests a dynamic pattern of duplication and loss of major floral patterning genes in this group and highlights the first case of a loss of CYC2 in a bilaterally symmetrical group. We illustrate here that CYC expression is conserved along the dorsoventral axis of the flower even as it turns upside-down, suggesting that at least late CYC expression is not regulated by extrinsic factors such as gravity. We additionally show that while the pattern of dorsoventral expression of each paralog remains the same, CamCYC2A is more dominant in species with shorter relative finally positioned dorsal lobes, and CamCYC2B is more dominant in species with long dorsal lobes.
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Sengupta A, Hileman LC. A CYC-RAD-DIV-DRIF interaction likely pre-dates the origin of floral monosymmetry in Lamiales. EvoDevo 2022; 13:3. [PMID: 35093179 PMCID: PMC8801154 DOI: 10.1186/s13227-021-00187-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 12/18/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND An outstanding question in evolutionary biology is how genetic interactions defining novel traits evolve. They may evolve either by de novo assembly of previously non-interacting genes or by en bloc co-option of interactions from other functions. We tested these hypotheses in the context of a novel phenotype-Lamiales flower monosymmetry-defined by a developmental program that relies on regulatory interaction among CYCLOIDEA, RADIALIS, DIVARICATA, and DRIF gene products. In Antirrhinum majus (snapdragon), representing Lamiales, we tested whether components of this program likely function beyond their previously known role in petal and stamen development. In Solanum lycopersicum (tomato), representing Solanales which diverged from Lamiales before the origin of Lamiales floral monosymmetry, we additionally tested for regulatory interactions in this program. RESULTS We found that RADIALIS, DIVARICATA, and DRIF are expressed in snapdragon ovaries and developing fruit, similar to their homologs during tomato fruit development. In addition, we found that a tomato CYCLOIDEA ortholog positively regulates a tomato RADIALIS ortholog. CONCLUSION Our results provide preliminary support to the hypothesis that the developmental program defining floral monosymmetry in Lamiales was co-opted en bloc from a function in carpel development. This expands our understanding of novel trait evolution facilitated by co-option of existing regulatory interactions.
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Affiliation(s)
- Aniket Sengupta
- Department of Ecology and Evolutionary Biology, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS, 66045, USA.
- St. Albert Hall, 8000 Utopia Pkwy, Room 257, Queens, NY, 11439, USA.
| | - Lena C Hileman
- Department of Ecology and Evolutionary Biology, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS, 66045, USA
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Ramage E, Soza VL, Yi J, Deal H, Chudgar V, Hall BD, Di Stilio VS. Gene Duplication and Differential Expression of Flower Symmetry Genes in Rhododendron (Ericaceae). PLANTS (BASEL, SWITZERLAND) 2021; 10:1994. [PMID: 34685803 PMCID: PMC8541606 DOI: 10.3390/plants10101994] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/20/2021] [Accepted: 09/20/2021] [Indexed: 01/11/2023]
Abstract
Bilaterally symmetric flowers have evolved over a hundred times in angiosperms, yet orthologs of the transcription factors CYCLOIDEA (CYC), RADIALIS (RAD), and DIVARICATA (DIV) are repeatedly implicated in floral symmetry changes. We examined these candidate genes to elucidate the genetic underpinnings of floral symmetry changes in florally diverse Rhododendron, reconstructing gene trees and comparing gene expression across floral organs in representative species with radial and bilateral flower symmetries. Radially symmetric R. taxifolium Merr. and bilaterally symmetric R. beyerinckianum Koord. had four and five CYC orthologs, respectively, from shared tandem duplications. CYC orthologs were expressed in the longer dorsal petals and stamens and highly expressed in R. beyerinckianum pistils, whereas they were either ubiquitously expressed, lost from the genome, or weakly expressed in R. taxifolium. Both species had two RAD and DIV orthologs uniformly expressed across all floral organs. Differences in gene structure and expression of Rhododendron RAD compared to other asterids suggest that these genes may not be regulated by CYC orthologs. Our evidence supports CYC orthologs as the primary regulators of differential organ growth in Rhododendron flowers, while also suggesting certain deviations from the typical asterid gene regulatory network for flower symmetry.
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Affiliation(s)
- Elizabeth Ramage
- Department of Biology, University of Washington, Seattle, WA 98195, USA; (E.R.); (H.D.); (V.C.); (B.D.H.); (V.S.D.S.)
| | - Valerie L. Soza
- Department of Biology, University of Washington, Seattle, WA 98195, USA; (E.R.); (H.D.); (V.C.); (B.D.H.); (V.S.D.S.)
| | - Jing Yi
- Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, School of Life Science, South China Normal University, Guangzhou 510631, China;
| | - Haley Deal
- Department of Biology, University of Washington, Seattle, WA 98195, USA; (E.R.); (H.D.); (V.C.); (B.D.H.); (V.S.D.S.)
| | - Vaidehi Chudgar
- Department of Biology, University of Washington, Seattle, WA 98195, USA; (E.R.); (H.D.); (V.C.); (B.D.H.); (V.S.D.S.)
| | - Benjamin D. Hall
- Department of Biology, University of Washington, Seattle, WA 98195, USA; (E.R.); (H.D.); (V.C.); (B.D.H.); (V.S.D.S.)
| | - Verónica S. Di Stilio
- Department of Biology, University of Washington, Seattle, WA 98195, USA; (E.R.); (H.D.); (V.C.); (B.D.H.); (V.S.D.S.)
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Zhou XR, Zhang NN, Zhao YM, Dai L, Xu DP, Xu GF, Tian J. Distribution Dynamics and Roles of Starch in Non-photosynthetic Vegetative Organs of Santalum album Linn., a Hemiparasitic Tree. FRONTIERS IN PLANT SCIENCE 2021; 11:532537. [PMID: 33584738 PMCID: PMC7873954 DOI: 10.3389/fpls.2020.532537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
Allocation dynamics of stored starch plays essential roles in the development and growth of trees. Previous studies focused on the dynamics and the characteristics of starch in autotrophic trees. However, although starch granules have been detected in the organs or tissues of some parasitic plants, studies on the allocation dynamics and roles of storage starch in them are limited. Therefore, we determined and estimated the allocation dynamics and roles of starch in Santalum album Linn., a hemiparasitic tree, using morphological and physiological methods. Our findings showed abundant starch in the stem and root of S. album at the early seedling stage. Although S. album seedlings attached to the host showed no significant changes in starch levels throughout the experiment, unattached and host-removed seedlings exhibited a gradual decrease in the starch content over time. When the starch content of unattached seedlings was less than 1%, they started to die. Starch accumulated to high levels in developing and active haustoria; however, starch levels were low in the inactive haustoria. The present study suggests that starch may provide energy to seedlings that have no host, allowing them to survive during the unattached phase, thus increasing their chance to attach to host roots by extending their survival duration. In addition, we speculate that storage starch is potentially involved in the development of haustoria and in the physiological processes of S. album related to the absorption and transportation of water and nutrients from its host.
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Affiliation(s)
- Xiu Ren Zhou
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Ning Nan Zhang
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Yi Min Zhao
- Guangxi Botanical Garden of Medicinal Plants, Nanning, China
| | - Lei Dai
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Da Ping Xu
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Gui Fang Xu
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
| | - Jing Tian
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, China
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Wessinger CA, Hileman LC. Parallelism in Flower Evolution and Development. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2020. [DOI: 10.1146/annurev-ecolsys-011720-124511] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Flower evolution is characterized by widespread repetition, with adaptations to pollinator environment evolving in parallel. Recent studies have expanded our understanding of the developmental basis of adaptive floral novelties—petal fusion, bilateral symmetry, heterostyly, and floral dimensions. In this article, we describe patterns of trait evolution and review developmental genetic mechanisms underlying floral novelties. We discuss the diversity of mechanisms for parallel adaptation, the evidence for constraints on these mechanisms, and how constraints help explain observed macroevolutionary patterns. We describe parallel evolution resulting from similarities at multiple hierarchical levels—genetic, developmental, morphological, functional—which indicate general principles in floral evolution, including the central role of hormone signaling. An emerging pattern is mutational bias that may contribute to rapid patterns of parallel evolution, especially if the derived trait can result from simple degenerative mutations. We argue that such mutational bias may be less likely to govern the evolution of novelties patterned by complex developmental pathways.
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Affiliation(s)
- Carolyn A. Wessinger
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Lena C. Hileman
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045, USA
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9
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Chen WH, Zhang YM, Guo SW, Zhang ZR, Chen L, Shui YM. Reassessment of Bournea Oliver (Gesneriaceae) based on molecular and palynological evidence. PHYTOKEYS 2020; 157:27-41. [PMID: 32934446 PMCID: PMC7467971 DOI: 10.3897/phytokeys..55254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 06/28/2020] [Indexed: 06/11/2023]
Abstract
The former genus Bournea is endemic to China, including two species, has been under consideration for incorporation into the expanded genus Oreocharis s.l. in Gesneriaceae. The phylogenetic tree inferred from two DNA sequences (trnL-F and ITS) showed that this genus is deeply nested into Oreocharis s.l. However, the new tree from seven ones (atpB-rbcL, ndhH-rps15-ycf1, rpl132, trnC-trnD, trnL-F, trnT-trnL of chloroplast DNA and ITS regions) revealed that Bournea is the sister group of other of Oreocharis s.l. Furthermore, Bournea is morphologically different from other Oreocharis based on existing data. We suggest keeping Bournea as an independent genus in Gesneriaceae.
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Affiliation(s)
- Wen-Hong Chen
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan Province, China
- Tropical Mountain Forest Eco-station in Southeast Yunnan, Pingbian 551200, Yunnan Province, China
| | - Ya-Mei Zhang
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan Province, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Shi-Wei Guo
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan Province, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi-Rong Zhang
- Germplasm Bank of Wild Species, Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan Province, China
| | - Li Chen
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan Province, China
- School of Life Sciences, Yunnan University, Kunming 650091, Yunnan Province, China
| | - Yu-Min Shui
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650201, Yunnan Province, China
- Tropical Mountain Forest Eco-station in Southeast Yunnan, Pingbian 551200, Yunnan Province, China
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Naghiloo S. Patterns of Symmetry Expression in Angiosperms: Developmental and Evolutionary Lability. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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11
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Roberts WR, Roalson EH. Co-expression clustering across flower development identifies modules for diverse floral forms in Achimenes (Gesneriaceae). PeerJ 2020; 8:e8778. [PMID: 32201652 PMCID: PMC7071821 DOI: 10.7717/peerj.8778] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/21/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Genetic pathways involved with flower color and shape are thought to play an important role in the development of flowers associated with different pollination syndromes, such as those associated with bee, butterfly, or hummingbird pollination. Because pollination syndromes are complex traits that are orchestrated by multiple genes and pathways, the gene regulatory networks have not been explored. Gene co-expression networks provide a systems level approach to identify important contributors to floral diversification. METHODS RNA-sequencing was used to assay gene expression across two stages of flower development (an early bud and an intermediate stage) in 10 species of Achimenes (Gesneriaceae). Two stage-specific co-expression networks were created from 9,503 orthologs and analyzed to identify module hubs and the network periphery. Module association with bee, butterfly, and hummingbird pollination syndromes was tested using phylogenetic mixed models. The relationship between network connectivity and evolutionary rates (d N/d S) was tested using linear models. RESULTS Networks contained 65 and 62 modules that were largely preserved between developmental stages and contained few stage-specific modules. Over a third of the modules in both networks were associated with flower color, shape, and pollination syndrome. Within these modules, several hub nodes were identified that related to the production of anthocyanin and carotenoid pigments and the development of flower shape. Evolutionary rates were decreased in highly connected genes and elevated in peripheral genes. DISCUSSION This study aids in the understanding of the genetic architecture and network properties underlying the development of floral form and provides valuable candidate modules and genes for future studies.
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Affiliation(s)
- Wade R. Roberts
- School of Biological Sciences, Washington State University, Pullman, WA, USA
- Biological Sciences, University of Arkansas, Fayetteville, AR, USA
| | - Eric H. Roalson
- School of Biological Sciences, Washington State University, Pullman, WA, USA
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Lu C, Pu Y, Liu Y, Li Y, Qu J, Huang H, Dai S. Comparative transcriptomics and weighted gene co-expression correlation network analysis (WGCNA) reveal potential regulation mechanism of carotenoid accumulation in Chrysanthemum × morifolium. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 142:415-428. [PMID: 31416008 DOI: 10.1016/j.plaphy.2019.07.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/24/2019] [Accepted: 07/26/2019] [Indexed: 05/23/2023]
Abstract
The variation of flower color of chrysanthemum (Chrysanthemum×morifolium) is extremely rich, and carotenoids, which are mainly stored in the plastid, are important pigments that determine the color of chrysanthemum. However, the genetic regulation of the carotenoid metabolism pathway in this species still remains unclear. In this study, a pink chrysanthemum cultivar, 'Jianliuxiang Pink', and its three bud sport mutants (including white, yellow and red color mutants, 'Jianliuxiang White', 'Jianliuxiang Yellow' and 'Jianliuxiang Red', respectively) were used as experimental materials to analyze the dynamic changes of carotenoid components and plastid ultrastructure at different developmental stages of ray florets. We found that the carotenoid components and plastid ultrastructure of the four color cultivars in the early developmental stage of the chrysanthemum capitulum (S1) were almost identical, and the carotenoids mainly included violaxanthin, lutein and β-carotene, which exist in proplastids and immature chloroplasts. With the development of capitulum, the chloroplasts in 'Jianliuxiang White' and 'Jianliuxiang Pink' were degraded, and the protoplasts did not transform but rather formed vesicles that accumulated trace amounts of carotenoids. The proplastids and chloroplasts in 'Jianliuxiang Yellow' and 'Jianliuxiang Red' were all transformed into chromoplasts and consist of lutein as well as lutein's isomer and derivatives. Using comparative transcriptomics combined with gene expression analysis, we found that CmPg-1, CmPAP10, and CmPAP13, which were involved in chromoplast transformation, CmLCYE, which was involved in carotenoid biosynthesis, and CmCCD4a-2, which was involved in carotenoid degradation, were differentially expressed between four cultivars, and these key genes therefore should affect the accumulation of carotenoids in chrysanthemum. In addition, six transcription factors, CmMYB305, CmMYB29, CmRAD3, CmbZIP61, CmAGL24, CmNAC1, were screened using weighted gene co-expression correlation network analysis (WGCNA) combined with correlative analysis to determine whether they play an important role in carotenoid accumulation by regulating structural genes related to the carotenoid metabolism pathway and plastid development. This study analyzed dynamic changes of carotenoid components and plastid ultrastructure of the four bud mutation cultivars of chrysanthemum and identified structural genes and transcription factors that may be involved in carotenoid accumulation. The above results laid a solid foundation for further analysis of the regulatory mechanism of the carotenoid biosynthesis pathway in chrysanthemum.
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Affiliation(s)
- Chenfei Lu
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing, 100083, China; National Engineering Research Center for Floriculture, Beijing, 100083, China; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China; College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Ya Pu
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing, 100083, China; National Engineering Research Center for Floriculture, Beijing, 100083, China; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China; College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Yuting Liu
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing, 100083, China; National Engineering Research Center for Floriculture, Beijing, 100083, China; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China; College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Yajun Li
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing, 100083, China; National Engineering Research Center for Floriculture, Beijing, 100083, China; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China; College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - Jiaping Qu
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing, 100083, China; National Engineering Research Center for Floriculture, Beijing, 100083, China; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China; College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China
| | - He Huang
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing, 100083, China; National Engineering Research Center for Floriculture, Beijing, 100083, China; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China; College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China.
| | - Silan Dai
- Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, Beijing, 100083, China; National Engineering Research Center for Floriculture, Beijing, 100083, China; Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China; College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China.
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Gene duplication and relaxation from selective constraints of GCYC genes correlated with various floral symmetry patterns in Asiatic Gesneriaceae tribe Trichosporeae. PLoS One 2019; 14:e0210054. [PMID: 30699126 PMCID: PMC6353098 DOI: 10.1371/journal.pone.0210054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 12/17/2018] [Indexed: 11/19/2022] Open
Abstract
Floral bilateral symmetry is one of the most important acquisitions in flower shape evolution in angiosperms. Members of Gesneriaceae possess predominantly zygomorphic flowers yet natural reversal to actinomorphy have independently evolved multiple times. The development of floral bilateral symmetry relies greatly on the gene CYCLOIDEA (CYC). Our reconstructed GCYC phylogeny indicated at least five GCYC duplication events occurred over the evolutionary history of Gesneriaceae. However, the patterns of GCYC expression following the duplications and the role of natural selection on GCYC copies in relation to floral symmetry remained largely unstudied. The Asiatic tribe Trichosporeae contains most reversals to actinomorphy. We thus investigated shifts in GCYC gene expression among selected zygomorphic species (Hemiboea bicornuta and Lysionotus pauciflorus) and species with reversals to actinomorphy (Conandron ramondioides) by RT-PCR. In the actinomorphic C. ramondioides, none of the three copies of GCYC was found expressed in petals implying that the reversal was a loss-of-function event. On the other hand, both zygomorphic species retained one GCYC1 copy that was expressed in the dorsal petals but each species utilized a different copy (GCYC1C for H. bicornuta and GCYC1D for L. pauciflorus). Together with previously published data, it appeared that GCYC1C and GCYC1D copies diversified their expression in a distinct species-specific pattern. To detect whether the selection signal (ω) changed before and after the duplication of GCYC1 in Asiatic Trichosporeae, we reconstructed a GCYC phylogeny using maximum likelihood and Bayesian inference algorithms and examined selection signals using PAML. The PAML analysis detected relaxation from selection right after the GCYC1 duplication (ωpre-duplication = 0.2819, ωpost-duplication = 0.3985) among Asiatic Trichosporeae species. We propose that the selection relaxation after the GCYC1 duplication created an "evolutionary window of flexibility" in which multiple copies were retained with randomly diverged roles for dorsal-specific expressions in association with floral symmetry changes.
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Valoroso MC, Sobral R, Saccone G, Salvemini M, Costa MMR, Aceto S. Evolutionary Conservation of the Orchid MYB Transcription Factors DIV, RAD, and DRIF. FRONTIERS IN PLANT SCIENCE 2019; 10:1359. [PMID: 31736999 PMCID: PMC6838138 DOI: 10.3389/fpls.2019.01359] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 10/02/2019] [Indexed: 05/02/2023]
Abstract
The MYB transcription factors DIVARICATA (DIV), DIV-and-RAD-Interacting-Factor (DRIF), and the small interfering peptide RADIALIS (RAD) can interact, forming a regulatory module that controls different plant developmental processes. In the snapdragon Antirrhinum majus, this module, together with the TCP transcription factor CYCLOIDEA (CYC), is responsible for the establishment of floral dorsoventral asymmetry. The spatial gene expression pattern of the OitDIV, OitDRIF, and OitRAD homologs of Orchis italica, an orchid with zygomorphic flowers, has suggested a possible conserved role of these genes in bilateral symmetry of the orchid flower. Here, we have identified four DRIF genes of orchids and have reconstructed their genomic organization and evolution. In addition, we found snapdragon transcriptional cis-regulatory elements of DIV and RAD loci generally conserved within the corresponding orchid orthologues. We have tested the biochemical interactions among OitDIV, OitDRIF1, and OitRAD of O. italica, showing that OitDRIF1 can interact both with OitDIV and OitRAD, whereas OitDIV and OitRAD do not directly interact, as in A. majus. The analysis of the quantitative expression profile of these MYB genes revealed that in zygomorphic orchid flowers, the DIV, DRIF1, and RAD transcripts are present at higher levels in the lip than in lateral inner tepals, whereas in peloric orchid flowers they show similar expression levels. These results indicate that MYB transcription factors could have a role in shaping zygomorphy of the orchid flower, potentially enriching the underlying orchid developmental code.
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Affiliation(s)
| | - Rómulo Sobral
- BioSystems & Integrative Sciences Institute (BioISI), Plant Functional Biology Centre, University of Minho, Campus de Gualtar, Braga, Portugal
| | - Giuseppe Saccone
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Marco Salvemini
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Maria Manuela Ribeiro Costa
- BioSystems & Integrative Sciences Institute (BioISI), Plant Functional Biology Centre, University of Minho, Campus de Gualtar, Braga, Portugal
| | - Serena Aceto
- Department of Biology, University of Naples Federico II, Naples, Italy
- *Correspondence: Serena Aceto,
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Hsin KT, Wang CN. Expression shifts of floral symmetry genes correlate to flower actinomorphy in East Asia endemic Conandron ramondioides (Gesneriaceae). BOTANICAL STUDIES 2018; 59:24. [PMID: 30374786 PMCID: PMC6206312 DOI: 10.1186/s40529-018-0242-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/22/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Bilateral symmetry flower (zygomorphy) is the ancestral state for Gesneriaceae species. Yet independent reversions to actinomorphy have been parallelly evolved in several lineages. Conandron ramondioides is a natural radially symmetrical species survived in dense shade mountainous habitats where specialist pollinators are scarce. Whether the mutations in floral symmetry genes such as CYC, RAD and DIV genes, or their expression pattern shifts contribute to the reversion to actinomorphy in C. ramondioides thus facilitating shifts to generalist pollinators remain to be investigated. To address this, we isolated putative orthologues of these genes and relate their expressions to developmental stages of flower actinomorphy. RESULTS Tissue specific RT-PCR found no dorsal identity genes CrCYCs and CrRADs expression in petal and stamen whorls, while the ventral identity gene CrDIV was expressed in all petals. Thus, ventralized actinomorphy is evolved in C. ramondioides. However, CrCYCs still persists their expression in sepal whorl. This is congruent with previous findings that CYC expression in sepals is an ancestral state common to both actinomorphic and zygomorphic core Eudicot species. CONCLUSIONS The loss of dorsal identity genes CrCYCs and CrRADs expression in petal and stamen whorl without mutating these genes specifies that a novel regulation change, possibly on cis-elements of these genes, has evolved to switch zygomorphy to actinomorphy.
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Affiliation(s)
- Kuan-Ting Hsin
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
| | - Chun-Neng Wang
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
- Department of Life Science, National Taiwan University, Taipei, Taiwan
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Hsu HJ, He CW, Kuo WH, Hsin KT, Lu JY, Pan ZJ, Wang CN. Genetic Analysis of Floral Symmetry Transition in African Violet Suggests the Involvement of Trans-acting Factor for CYCLOIDEA Expression Shifts. FRONTIERS IN PLANT SCIENCE 2018; 9:1008. [PMID: 30158940 PMCID: PMC6104639 DOI: 10.3389/fpls.2018.01008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 06/21/2018] [Indexed: 05/29/2023]
Abstract
With the growing demand for its ornamental uses, the African violet (Saintpaulia ionantha) has been popular owing to its variations in color, shape and its rapid responses to artificial selection. Wild type African violet (WT) is characterized by flowers with bilateral symmetry yet reversals showing radially symmetrical flowers such as dorsalized actinomorphic (DA) and ventralized actinomorphic (VA) peloria are common. Genetic crosses among WT, DA, and VA revealed that these floral symmetry transitions are likely to be controlled by three alleles at a single locus in which the levels of dominance are in a hierarchical fashion. To investigate whether the floral symmetry gene was responsible for these reversals, orthologs of CYCLOIDEA (CYC) were isolated and their expressions correlated to floral symmetry transitions. Quantitative RT-PCR and in situ results indicated that dorsal-specific CYCs expression in WT S. ionantha (SiCYC and SiCYC1B) shifted in DA with a heterotopically extended expression to all petals, but in VA, SiCYC1s' dorsally specific expressions were greatly reduced. Selection signature analysis revealed that the major high-expressed copy of SiCYC had been constrained under purifying selection, whereas the low-expressed helper SiCYC1B appeared to be relaxed under purifying selection after the duplication into SiCYC and SiCYC1B. Heterologous expression of SiCYC in Arabdiopsis showed petal growth retardation which was attributed to limited cell proliferation. While expression shifts of SiCYC and SiCYC1B correlate perfectly to the resulting symmetry phenotype transitions in F1s of WT and DA, there is no certain allelic combination of inherited SiCYC1s associated with specific symmetry phenotypes. This floral transition indicates that although the expression shifts of SiCYC/1B are responsible for the two contrasting actinomorphic reversals in African violet, they are likely to be controlled by upstream trans-acting factors or epigenetic regulations.
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Affiliation(s)
- Hui-Ju Hsu
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
| | - Cheng-Wen He
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
| | - Wen-Hsi Kuo
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
| | - Kuan-Ting Hsin
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
| | - Jing-Yi Lu
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Zhao-Jun Pan
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Chun-Neng Wang
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan
- Department of Life Science, National Taiwan University, Taipei, Taiwan
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Spencer V, Kim M. Re“CYC”ling molecular regulators in the evolution and development of flower symmetry. Semin Cell Dev Biol 2018; 79:16-26. [DOI: 10.1016/j.semcdb.2017.08.052] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/28/2017] [Indexed: 11/27/2022]
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Sengupta A, Hileman LC. Novel Traits, Flower Symmetry, and Transcriptional Autoregulation: New Hypotheses From Bioinformatic and Experimental Data. FRONTIERS IN PLANT SCIENCE 2018; 9:1561. [PMID: 30416508 PMCID: PMC6212560 DOI: 10.3389/fpls.2018.01561] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/05/2018] [Indexed: 05/18/2023]
Abstract
A common feature in developmental networks is the autoregulation of transcription factors which, in turn, positively or negatively regulate additional genes critical for developmental patterning. When a transcription factor regulates its own expression by binding to cis-regulatory sites in its gene, the regulation is direct transcriptional autoregulation (DTA). Indirect transcriptional autoregulation (ITA) involves regulation by proteins expressed downstream of the target transcription factor. We review evidence for a hypothesized role of DTA in the evolution and development of novel flowering plant phenotypes. We additionally provide new bioinformatic and experimental analyses that support a role for transcriptional autoregulation in the evolution of flower symmetry. We find that 5' upstream non-coding regions are significantly enriched for predicted autoregulatory sites in Lamiales CYCLOIDEA genes-an upstream regulator of flower monosymmetry. This suggests a possible correlation between autoregulation of CYCLOIDEA and the origin of monosymmetric flowers near the base of Lamiales, a pattern that may be correlated with independently derived monosymmetry across eudicot lineages. We find additional evidence for transcriptional autoregulation in the flower symmetry program, and report that Antirrhinum DRIF2 may undergo ITA. In light of existing data and new data presented here, we hypothesize how cis-acting autoregulatory sites originate, and find evidence that such sites (and DTA) can arise subsequent to the evolution of a novel phenotype.
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Berger BA, Ricigliano VA, Savriama Y, Lim A, Thompson V, Howarth DG. Geometric morphometrics reveals shifts in flower shape symmetry and size following gene knockdown of CYCLOIDEA and ANTHOCYANIDIN SYNTHASE. BMC PLANT BIOLOGY 2017; 17:205. [PMID: 29149840 PMCID: PMC5693587 DOI: 10.1186/s12870-017-1152-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 11/07/2017] [Indexed: 05/14/2023]
Abstract
BACKGROUND While floral symmetry has traditionally been assessed qualitatively, recent advances in geometric morphometrics have opened up new avenues to specifically quantify flower shape and size using robust multivariate statistical methods. In this study, we examine, for the first time, the ability of geometric morphometrics to detect morphological differences in floral dorsoventral asymmetry following virus-induced gene silencing (VIGS). Using Fedia graciliflora Fisch. & Meyer (Valerianaceae) as a model, corolla shape of untreated flowers was compared using canonical variate analysis to knockdown phenotypes of CYCLOIDEA2A (FgCYC2A), ANTHOCYANIDIN SYNTHASE (FgANS), and empty vector controls. RESULTS Untreated flowers and all VIGS treatments were morphologically distinct from each other, suggesting that VIGS may cause subtle shifts in floral shape. Knockdowns of FgCYC2A were the most dramatic, affecting the position of dorsal petals in relation to lateral petals, thereby resulting in more actinomorphic-like flowers. Additionally, FgANS knockdowns developed larger flowers with wider corolla tube openings. CONCLUSIONS These results provide a method to quantify the role that specific genes play in the developmental pathway affecting the dorsoventral axis of symmetry in zygomorphic flowers. Additionally, they suggest that ANS may have an unintended effect on floral size and shape.
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Affiliation(s)
- Brent A. Berger
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, NY 11439 USA
| | | | - Yoland Savriama
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, NY 11439 USA
- Institute of Biotechnology, University of Helsinki, PO Box 56 (Viikinkaari 5), FI-00014 Helsinki, Finland
| | - Aedric Lim
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, NY 11439 USA
| | - Veronica Thompson
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, NY 11439 USA
| | - Dianella G. Howarth
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, NY 11439 USA
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Su S, Xiao W, Guo W, Yao X, Xiao J, Ye Z, Wang N, Jiao K, Lei M, Peng Q, Hu X, Huang X, Luo D. The CYCLOIDEA-RADIALIS module regulates petal shape and pigmentation, leading to bilateral corolla symmetry in Torenia fournieri (Linderniaceae). THE NEW PHYTOLOGIST 2017; 215:1582-1593. [PMID: 28691160 DOI: 10.1111/nph.14673] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 05/24/2017] [Indexed: 05/04/2023]
Abstract
The diverse pigmentation patterns of flower corollas probably result from pollinator-mediated selection. Previous studies demonstrated that R2R3-MYB factors may have been recruited in the regulation of corolla pigmentation. However, how R2R3-MYBs became so diverse in their regulation of different pigmentation patterns remains unclear. Here, we studied a Lamiales species, Torenia fournieri, which has elaborate zygomorphic flowers with dorsal-ventral asymmetries in corolla pigmentation. We found recent gene duplication events in CYCLOIDEA-like (CYC-like) and RADIALIS-like (RAD-like) genes, and functionally analyzed three dorsal-specific expression factors: TfCYC1, TfCYC2, and TfRAD1. We found that the CYC-RAD module coordinates petal shape and corolla pigmentation, as ectopic expression of TfCYC2 or TfRAD1 disrupted the asymmetric corolla pigmentation pattern and produced strongly dorsalized flowers. Dorsal petal identity was lost when TfCYC2 was down-regulated or when TfRAD1 was knocked out. In T. fournieri, the diversified CYC and RAD genes have evolved regulatory loops, and TfCYC2 binds directly to the regulatory regions of an R2R3-MYB factor gene, TfMYB1, which might lead to its asymmetric expression and ultimately establish the asymmetric pigmentation pattern. These findings support the existence of a regulatory module that integrates dorsal-ventral patterning and asymmetric corolla pigmentation in T. fournieri.
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Affiliation(s)
- Shihao Su
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Wei Xiao
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Wuxiu Guo
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xinran Yao
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Junqing Xiao
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Ziqing Ye
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Na Wang
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Keyuan Jiao
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Mengqi Lei
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Qincheng Peng
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xiaohe Hu
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xia Huang
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Da Luo
- State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
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Zhong J, Preston JC, Hileman LC, Kellogg EA. Repeated and diverse losses of corolla bilateral symmetry in the Lamiaceae. ANNALS OF BOTANY 2017; 119:1211-1223. [PMID: 28334152 PMCID: PMC5604593 DOI: 10.1093/aob/mcx012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 01/30/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND AND AIMS Independent evolution of derived complex characters provides a unique opportunity to assess whether and how similar genetic changes correlate with morphological convergence. Bilaterally symmetrical corollas have evolved multiple times independently from radially symmetrical ancestors and likely represent adaptations to attract specific pollinators. On the other hand, losses of bilateral corolla symmetry have occurred sporadically in various groups, due to either modification of bilaterally symmetrical corollas in late development or early establishment of radial symmetry. METHODS This study integrated phylogenetic, scanning electron microscopy (SEM)-based morphological, and gene expression approaches to assess the possible mechanisms underlying independent evolutionary losses of corolla bilateral symmetry. KEY RESULTS This work compared three species of Lamiaceae having radially symmetrical mature corollas with a representative sister taxon having bilaterally symmetrical corollas and found that each reaches radial symmetry in a different way. Higher core Lamiales share a common duplication in the CYCLOIDEA (CYC ) 2 gene lineage and show conserved and asymmetrical expression of CYC2 clade and RAD genes along the adaxial-abaxial floral axis in species having bilateral corolla symmetry. In Lycopus americanus , the development and expression pattern of La-CYC2A and La-CYC2B are similar to those of their bilaterally symmetrical relatives, whereas the loss of La-RAD expression correlates with a late switch to radial corolla symmetry. In Mentha longifolia , late radial symmetry may be explained by the loss of Ml-CYC2A , and by altered expression of two Ml-CYC2B and Ml-RAD genes . Finally, expanded expression of Cc-CYC2A and Cc-RAD strongly correlates with the early development of radially symmetrical corollas in Callicarpa cathayana . CONCLUSIONS Repeated losses of mature corolla bilateral symmetry in Lamiaceae are not uncommon, and may be achieved by distinct mechanisms and various changes to symmetry genes, including the loss of a CYC2 clade gene from the genome, and/or contraction, expansion or alteration of CYC2 clade and RAD -like gene expression.
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Affiliation(s)
- Jinshun Zhong
- Department of Biology, The University of Missouri-St. Louis, One University Blvd, St. Louis, MO 63121, USA
- Department of Plant Biology, The University of Vermont, 63 Carrigan Drive, Burlington, VT 05405, USA
- For correspondence. E-mail
| | - Jill C. Preston
- Department of Plant Biology, The University of Vermont, 63 Carrigan Drive, Burlington, VT 05405, USA
- Department of Ecology and Evolutionary Biology, The University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA
| | - Lena C. Hileman
- Department of Ecology and Evolutionary Biology, The University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA
| | - Elizabeth A. Kellogg
- Department of Biology, The University of Missouri-St. Louis, One University Blvd, St. Louis, MO 63121, USA
- Donald Danforth Plant Science Center, 975 N Warson Road, St. Louis, MO 63132, USA
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Hsu HC, Wang CN, Liang CH, Wang CC, Kuo YF. Association between Petal Form Variation and CYC2-like Genotype in a Hybrid Line of Sinningia speciosa. FRONTIERS IN PLANT SCIENCE 2017; 8:558. [PMID: 28458679 PMCID: PMC5394160 DOI: 10.3389/fpls.2017.00558] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 03/28/2017] [Indexed: 05/20/2023]
Abstract
This study used three-dimensional (3D) micro-computed tomography (μCT) imaging to examine petal form variation in a hybrid cross of Sinningia speciosa between a cultivar with actinomorphic flowers and a variety with zygomorphic flowers. The major objectives were to determine the genotype-phenotype associations between the petal form variation and CYCLOIDEA2-like alleles in S. speciosa (SsCYC) and to morphologically investigate the differences in petal types between actinomorphic and zygomorphic flowers. In this study, μCT was used to accurately acquire 3D floral images. Landmark-based geometric morphometrics (GM) was applied to evaluate the major form variations of the petals. Nine morphological traits of the petals were defined according to the form variations quantified through the GM analysis. The results indicated that the outward curvature of dorsal petals, the midrib asymmetry of lateral petals, and the dilation of ventral region of the tube were closely associated with the SsCYC genotype. Multiple analyses of form similarity between the petals suggested that the dorsal and ventral petals of actinomorphic plants resembled the ventral petals of zygomorphic plants. This observation indicated that the transition from zygomorphic to actinomorphic flowers in S. speciosa might be caused by the ventralization of the dorsal petals. We demonstrated that the 3D-GM approach can be used to determine genotype-phenotype associations and to provide morphological evidence for the transition of petal types between actinomorphic and zygomorphic flowers in S. speciosa.
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Affiliation(s)
- Hao-Chun Hsu
- Department of Bio-Industrial Mechatronics Engineering, National Taiwan UniversityTaipei, Taiwan
| | - Chun-Neng Wang
- Institute of Ecology and Evolutionary Biology, National Taiwan UniversityTaipei, Taiwan
- Department of Life Science, National Taiwan UniversityTaipei, Taiwan
| | - Chia-Hao Liang
- Department of Bio-Industrial Mechatronics Engineering, National Taiwan UniversityTaipei, Taiwan
| | - Cheng-Chun Wang
- Department of Bio-Industrial Mechatronics Engineering, National Taiwan UniversityTaipei, Taiwan
| | - Yan-Fu Kuo
- Department of Bio-Industrial Mechatronics Engineering, National Taiwan UniversityTaipei, Taiwan
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Citerne HL, Reyes E, Le Guilloux M, Delannoy E, Simonnet F, Sauquet H, Weston PH, Nadot S, Damerval C. Characterization of CYCLOIDEA-like genes in Proteaceae, a basal eudicot family with multiple shifts in floral symmetry. ANNALS OF BOTANY 2017; 119:367-378. [PMID: 28025288 PMCID: PMC5314643 DOI: 10.1093/aob/mcw219] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 05/17/2016] [Accepted: 09/14/2016] [Indexed: 05/08/2023]
Abstract
BACKGROUND AND AIMS The basal eudicot family Proteaceae (approx. 1700 species) shows considerable variation in floral symmetry but has received little attention in studies of evolutionary development at the genetic level. A framework for understanding the shifts in floral symmetry in Proteaceae is provided by reconstructing ancestral states on an upated phylogeny of the family, and homologues of CYCLOIDEA (CYC), a key gene for the control of floral symmetry in both monocots and eudicots, are characterized. METHODS Perianth symmetry transitions were reconstructed on a new species-level tree using parsimony and maximum likelihood. CYC-like genes in 35 species (31 genera) of Proteaceae were sequenced and their phylogeny was reconstructed. Shifts in selection pressure following gene duplication were investigated using nested branch-site models of sequence evolution. Expression patterns of CYC homologues were characterized in three species of Grevillea with different types of floral symmetry. KEY RESULTS Zygomorphy has evolved 10-18 times independently in Proteaceae from actinomorphic ancestors, with at least four reversals to actinomorphy. A single duplication of CYC-like genes occurred prior to the diversification of Proteaceae, with putative loss or divergence of the ProtCYC1 paralogue in more than half of the species sampled. No shifts in selection pressure were detected in the branches subtending the two ProtCYC paralogues. However, the amino acid sequence preceding the TCP domain is strongly divergent in Grevillea ProtCYC1 compared with other species. ProtCYC genes were expressed in developing flowers of both actinomorphic and zygomorphic Grevillea species, with late asymmetric expression in the perianth of the latter. CONCLUSION Proteaceae is a remarkable family in terms of the number of transitions in floral symmetry. Furthermore, although CYC-like genes in Grevillea have unusual sequence characteristics, they display patterns of expression that make them good candidates for playing a role in the establishment of floral symmetry.
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Affiliation(s)
- Hélène L Citerne
- Génétique Quantitative et Evolution-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Elisabeth Reyes
- Laboratoire Ecologie, Systématique et Evolution, UMR 8079 Université Paris-Sud, CNRS, AgroParisTech, 91405 Orsay, France
| | - Martine Le Guilloux
- Génétique Quantitative et Evolution-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Etienne Delannoy
- Institute of Plant Sciences Paris Saclay IPS2, CNRS, INRA, Université Paris-Sud, Université Evry, Université Paris-Saclay, Université Paris Diderot, Sorbonne Paris-Cité, Bâtiment 630, 91405 Orsay, France
| | - Franck Simonnet
- Génétique Quantitative et Evolution-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Hervé Sauquet
- Laboratoire Ecologie, Systématique et Evolution, UMR 8079 Université Paris-Sud, CNRS, AgroParisTech, 91405 Orsay, France
| | - Peter H Weston
- National Herbarium of New South Wales, The Royal Botanic Garden Sydney, Australia
| | - Sophie Nadot
- Laboratoire Ecologie, Systématique et Evolution, UMR 8079 Université Paris-Sud, CNRS, AgroParisTech, 91405 Orsay, France
| | - Catherine Damerval
- Génétique Quantitative et Evolution-Le Moulon, INRA, Université Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
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Bello MA, Cubas P, Álvarez I, Sanjuanbenito G, Fuertes-Aguilar J. Evolution and Expression Patterns of CYC/TB1 Genes in Anacyclus: Phylogenetic Insights for Floral Symmetry Genes in Asteraceae. FRONTIERS IN PLANT SCIENCE 2017; 8:589. [PMID: 28487706 PMCID: PMC5403951 DOI: 10.3389/fpls.2017.00589] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 03/31/2017] [Indexed: 05/20/2023]
Abstract
Homologs of the CYC/TB1 gene family have been independently recruited many times across the eudicots to control aspects of floral symmetry The family Asteraceae exhibits the largest known diversification in this gene paralog family accompanied by a parallel morphological floral richness in its specialized head-like inflorescence. In Asteraceae, whether or not CYC/TB1 gene floral symmetry function is preserved along organismic and gene lineages is unknown. In this study, we used phylogenetic, structural and expression analyses focused on the highly derived genus Anacyclus (tribe Anthemidae) to address this question. Phylogenetic reconstruction recovered eight main gene lineages present in Asteraceae: two from CYC1, four from CYC2 and two from CYC3-like genes. The species phylogeny was recovered in most of the gene lineages, allowing the delimitation of orthologous sets of CYC/TB1 genes in Asteraceae. Quantitative real-time PCR analysis indicated that in Anacyclus three of the four isolated CYC2 genes are more highly expressed in ray flowers. The expression of the four AcCYC2 genes overlaps in several organs including the ligule of ray flowers, as well as in anthers and ovules throughout development.
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Affiliation(s)
- María A. Bello
- Plant Evolutionary Biology Group, Real Jardín Botánico (CSIC)Madrid, Spain
| | - Pilar Cubas
- Department of Plant Molecular Genetics, Centro Nacional de Biotecnología, CSIC-Universidad Autónoma de MadridMadrid, Spain
| | - Inés Álvarez
- Plant Evolutionary Biology Group, Real Jardín Botánico (CSIC)Madrid, Spain
| | | | - Javier Fuertes-Aguilar
- Plant Evolutionary Biology Group, Real Jardín Botánico (CSIC)Madrid, Spain
- *Correspondence: Javier Fuertes-Aguilar
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Berger BA, Thompson V, Lim A, Ricigliano V, Howarth DG. Elaboration of bilateral symmetry across Knautia macedonica capitula related to changes in ventral petal expression of CYCLOIDEA-like genes. EvoDevo 2016; 7:8. [PMID: 27042288 PMCID: PMC4818532 DOI: 10.1186/s13227-016-0045-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 02/10/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Shifts in floral form across angiosperms, particularly from radially symmetrical to bilaterally symmetrical flowers, are often associated with shifts in speciation rates and changes in pollination syndrome. Growing evidence across both rosids and asterids indicates that CYCLOIDEA (CYC)-like transcription factors from the TCP gene family play a role in establishing the dorsoventral pattern of flower symmetry, which affects the development of both the corolla and androecium. Previous studies of CYC-like genes, especially of the CYC2 clade, indicate that these genes are dorsally restricted in bilaterally symmetrical flowers. Also, gene duplication of CYC-like genes often correlates with shifts in floral form in both individual flowers and head-like inflorescences (capitula). RESULTS Here, we compared the expression patterns of six CYC-like genes from dorsal, lateral, and ventral petals of internal and external florets across capitula of Knautia macedonica (Dipsacaceae). We demonstrate that multiple copies of CYC-like genes are differentially expressed among petal types and between internal and external florets. Across paralogs, there was a general trend toward a reduction in dorsal expression and an increase in ventral expression in internal florets compared to external florets. However, it was in the ventral petals where a statistically significant increase in expression correlates with a less zygomorphic flower. We also show for the first time lateral-specific expression of a CYC-like gene. Additionally, dorsoventral asymmetric expression of a CYC3 paralog indicates that this understudied gene clade is likely also involved in floral symmetry. CONCLUSIONS These data indicate that the elaboration of bilateral symmetry may be regulated by the dorsoventral gradient of expression, with statistically significant changes in ventral expression correlating with changes in dorsoventral morphological specialization.
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Affiliation(s)
- Brent A Berger
- Department of Botany, University of Wisconsin-Madison, 430 Lincoln Dr., Madison, WI 53706 USA ; Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439 USA
| | - Veronica Thompson
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439 USA
| | - Aedric Lim
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439 USA
| | - Vincent Ricigliano
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439 USA
| | - Dianella G Howarth
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439 USA
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Zhong J, Kellogg EA. Stepwise evolution of corolla symmetry in CYCLOIDEA2-like and RADIALIS-like gene expression patterns in Lamiales. AMERICAN JOURNAL OF BOTANY 2015; 102:1260-7. [PMID: 26290549 DOI: 10.3732/ajb.1500191] [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: 04/30/2015] [Accepted: 07/07/2015] [Indexed: 05/09/2023]
Abstract
UNLABELLED • PREMISE OF THE STUDY CYCLOIDEA2 (CYC2)-like and RADIALIS (RAD)-like genes are needed for the normal development of corolla bilateral symmetry in Antirrhinum majus L. (snapdragon, Plantaginaceae, Lamiales). However, if and how changes in expression of CYC2-like and RAD-like genes correlate with the origin of corolla bilateral symmetry early in Lamiales remains largely unknown. The asymmetrical expression of CYC2-like and/or RAD-like genes during floral meristem development could be ancestral or derived in Plantaginaceae.• METHODS We used in situ RNA localization to examine the expression of CYC2-like and RAD-like genes in two early-diverging Lamiales.• KEY RESULTS CYC2-like and RAD-like genes are expressed broadly in the floral meristems in early-diverging Lamiales with radially symmetrical corollas, in contrast to their restricted expression in adaxial/lateral regions in core Lamiales. The expression pattern of CYC2-like genes has evolved in stepwise fashion, in that CYC2-like genes are likely expressed briefly in the floral meristem during flower development in sampled Oleaceae; prolonged expression of CYC2-like genes in petals originated in the common ancestor of Tetrachondraceae and core Lamiales, and asymmetrical expression in adaxial/lateral petals appeared later, in the common ancestor of the core Lamiales. Likewise, expression of RAD-like genes in petals appeared in early-diverging Lamiales or earlier; asymmetrical expression in adaxial/lateral petals then appeared in core Lamiales.• CONCLUSIONS These data plus published reports of CYC2-like and RAD-like genes show that asymmetrical expression of these two genes is likely derived and correlates with the origins of corolla bilateral symmetry.
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Affiliation(s)
- Jinshun Zhong
- Department of Biology, The University of Missouri - St. Louis, One University Boulevard, St. Louis, Missouri 63121 USA
| | - Elizabeth A Kellogg
- Department of Biology, The University of Missouri - St. Louis, One University Boulevard, St. Louis, Missouri 63121 USA
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27
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Specht CD, Howarth DG. Adaptation in flower form: a comparative evodevo approach. THE NEW PHYTOLOGIST 2015; 206:74-90. [PMID: 25470511 DOI: 10.1111/nph.13198] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 10/15/2014] [Indexed: 05/10/2023]
Abstract
Evolutionary developmental biology (evodevo) attempts to explain how the process of organismal development evolves, utilizing a comparative approach to investigate changes in developmental pathways and processes that occur during the evolution of a given lineage. Evolutionary genetics uses a population approach to understand how organismal changes in form or function are linked to underlying genetics, focusing on changes in gene and genotype frequencies within populations and the fixation of genotypic variation into traits that define species or evoke speciation events. Microevolutionary processes, including mutation, genetic drift, natural selection and gene flow, can provide the foundation for macroevolutionary patterns observed as morphological evolution and adaptation. The temporal element linking microevolutionary processes to macroevolutionary patterns is development: an organism's genotype is converted to phenotype by ontogenetic processes. Because selection acts upon the phenotype, the connection between evolutionary genetics and developmental evolution becomes essential to understanding adaptive evolution in organismal form and function. Here, we discuss how developmental genetic studies focused on key developmental processes could be linked within a comparative framework to study the developmental genetics of adaptive evolution, providing examples from research on two key processes of plant evodevo - floral symmetry and organ fusion - and their role in the adaptation of floral form.
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Affiliation(s)
- Chelsea D Specht
- Departments of Plant and Microbial Biology, Integrative Biology, and the University and Jepson Herbaria, University of California, 111 Koshland Hall, Berkeley, CA, 94720, USA
| | - Dianella G Howarth
- Department of Biological Sciences, St John's University, 8000 Utopia Pkwy, Jamaica, NY, 11439, USA
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28
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Hileman LC. Trends in flower symmetry evolution revealed through phylogenetic and developmental genetic advances. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0348. [PMID: 24958922 DOI: 10.1098/rstb.2013.0348] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A striking aspect of flowering plant (angiosperm) diversity is variation in flower symmetry. From an ancestral form of radial symmetry (polysymmetry, actinomorphy), multiple evolutionary transitions have contributed to instances of non-radial forms, including bilateral symmetry (monosymmetry, zygomorphy) and asymmetry. Advances in flowering plant molecular phylogenetic research and studies of character evolution as well as detailed flower developmental genetic studies in a few model species (e.g. Antirrhinum majus, snapdragon) have provided a foundation for deep insights into flower symmetry evolution. From phylogenetic studies, we have a better understanding of where during flowering plant diversification transitions from radial to bilateral flower symmetry (and back to radial symmetry) have occurred. From developmental studies, we know that a genetic programme largely dependent on the functional action of the CYCLOIDEA gene is necessary for differentiation along the snapdragon dorsoventral flower axis. Bringing these two lines of inquiry together has provided surprising insights into both the parallel recruitment of a CYC-dependent developmental programme during independent transitions to bilateral flower symmetry, and the modifications to this programme in transitions back to radial flower symmetry, during flowering plant evolution.
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Affiliation(s)
- Lena C Hileman
- Ecology and Evolutionary Biology, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA
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Zhong J, Kellogg EA. Duplication and expression of CYC2-like genes in the origin and maintenance of corolla zygomorphy in Lamiales. THE NEW PHYTOLOGIST 2015; 205:852-868. [PMID: 25329857 DOI: 10.1111/nph.13104] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/29/2014] [Indexed: 05/28/2023]
Abstract
Duplication, retention, and expression of CYCLOIDEA2 (CYC2)-like genes are thought to affect evolution of corolla symmetry. However, exactly what and how changes in CYC2-like genes correlate with the origin of corolla zygomorphy are poorly understood. We inferred and calibrated a densely sampled phylogeny of CYC2-like genes across the Lamiales and examined their expression in early diverging (EDL) and higher core clades (HCL). CYC2-like genes duplicated extensively in Lamiales, at least six times in core Lamiales (CL) around the Cretaceous-Paleogene (K-Pg) boundary, and seven more in EDL relatively more recently. Nested duplications and losses of CYC2-like paralogs are pervasive but may not correlate with transitions in corolla symmetry. We found evidence for dN/dS (ω) variation following gene duplications. CYC2-like paralogs in HCL show differential expression with higher expression in adaxial petals. Asymmetric expression but not recurrent duplication of CYC2-like genes correlates with the origin of corolla zygomorphy. Changes in both cis-regulatory and coding domains of CYC2-like genes are probably crucial for the evolution of corolla zygomorphy. Multiple selection regimes appear likely to play important roles in gene retention. The parallel duplications of CYC2-like genes are after the initial diversification of bumble bees and Euglossine bees.
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Affiliation(s)
- Jinshun Zhong
- Department of Biology, The University of Missouri-St Louis, One University Blvd, St Louis, MO, 63121, USA; Department of Plant Biology, The University of Vermont, Carrigan Drive, Burlington, VT 05405, USA
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Zhang Y, Zhang J, Song T, Li J, Tian J, Jin K, Yao Y. Low medium pH value enhances anthocyanin accumulation in Malus crabapple leaves. PLoS One 2014; 9:e97904. [PMID: 24914811 PMCID: PMC4051612 DOI: 10.1371/journal.pone.0097904] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/24/2014] [Indexed: 12/14/2022] Open
Abstract
Anthocyanin is a critical factor involved in coloration of plant tissues, but the mechanism how medium pH values affect anthocyanin accumulation in woody plants is unknown. We analyzed anthocyanin composition and the expression of elements encoding anthocyanin and flavonols biosynthesis underlying different medium pH values by using three different leave color type cultivars. HPLC analysis demonstrated that high medium pH values treatment induced a dramatic decrease in the concentration of cyaniding in crabapple leaves. Conversely, the high medium pH values induced up-regulation of the content of flavones and flavonols, suggesting that low pH treatment-induced anthocyanin accumulation. Quantitative real time PCR experiment showed the expression level of anthocyanidin synthase (McANS) and uridine diphosphate glucose flavonoid 3-O-glucosyltransferase (McUFGT) was up-regulated by low pH values treatment, and high medium pH value treatment up-regulate the transcription level of flavonol synthase (McFLS). Meanwhile, several MYB TFs have been suggested in the regulation of pH responses. These results strongly indicate that the low pH treatment-induced anthocyanin accumulation is mediated by the variation of mRNA transcription of the anthocyanin biosynthetic genes.
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Affiliation(s)
- Yanchen Zhang
- Plant Science and Technology College, Beijing University of Agriculture, Beijing, China
| | - Jie Zhang
- Plant Science and Technology College, Beijing University of Agriculture, Beijing, China
- Key Laboratory of New Technology in Agricultural Application of Beijing, Beijing University of Agriculture, Beijing, China
| | - Tingting Song
- Plant Science and Technology College, Beijing University of Agriculture, Beijing, China
- Key Laboratory of New Technology in Agricultural Application of Beijing, Beijing University of Agriculture, Beijing, China
| | - Jinyan Li
- Plant Science and Technology College, Beijing University of Agriculture, Beijing, China
| | - Ji Tian
- Plant Science and Technology College, Beijing University of Agriculture, Beijing, China
- Key Laboratory of New Technology in Agricultural Application of Beijing, Beijing University of Agriculture, Beijing, China
| | - Kaina Jin
- Plant Science and Technology College, Beijing University of Agriculture, Beijing, China
| | - Yuncong Yao
- Plant Science and Technology College, Beijing University of Agriculture, Beijing, China
- Key Laboratory of New Technology in Agricultural Application of Beijing, Beijing University of Agriculture, Beijing, China
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Jabbour F, Cossard G, Le Guilloux M, Sannier J, Nadot S, Damerval C. Specific duplication and dorsoventrally asymmetric expression patterns of Cycloidea-like genes in zygomorphic species of Ranunculaceae. PLoS One 2014; 9:e95727. [PMID: 24752428 PMCID: PMC3994137 DOI: 10.1371/journal.pone.0095727] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 03/28/2014] [Indexed: 11/23/2022] Open
Abstract
Floral bilateral symmetry (zygomorphy) has evolved several times independently in angiosperms from radially symmetrical (actinomorphic) ancestral states. Homologs of the Antirrhinum majus Cycloidea gene (Cyc) have been shown to control floral symmetry in diverse groups in core eudicots. In the basal eudicot family Ranunculaceae, there is a single evolutionary transition from actinomorphy to zygomorphy in the stem lineage of the tribe Delphinieae. We characterized Cyc homologs in 18 genera of Ranunculaceae, including the four genera of Delphinieae, in a sampling that represents the floral morphological diversity of this tribe, and reconstructed the evolutionary history of this gene family in Ranunculaceae. Within each of the two RanaCyL (Ranunculaceae Cycloidea-like) lineages previously identified, an additional duplication possibly predating the emergence of the Delphinieae was found, resulting in up to four gene copies in zygomorphic species. Expression analyses indicate that the RanaCyL paralogs are expressed early in floral buds and that the duration of their expression varies between species and paralog class. At most one RanaCyL paralog was expressed during the late stages of floral development in the actinomorphic species studied whereas all paralogs from the zygomorphic species were expressed, composing a species-specific identity code for perianth organs. The contrasted asymmetric patterns of expression observed in the two zygomorphic species is discussed in relation to their distinct perianth architecture.
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Affiliation(s)
- Florian Jabbour
- Université Paris-Sud, UMR 0320/UMR 8120, Génétique Végétale, Gif-sur-Yvette, France
- Université Paris-Sud, Laboratoire Ecologie, Systématique, Evolution, CNRS UMR 8079, AgroParisTech, Orsay, France
- Systematic Botany and Mycology, University of Munich (LMU), Munich, Germany
- Muséum National d'Histoire Naturelle, Institut de Systématique, Evolution, Biodiversité, UMR 7205 ISYEB MNHN-CNRS-UPMC-EPHE, Paris, France
| | - Guillaume Cossard
- Université Paris-Sud, Laboratoire Ecologie, Systématique, Evolution, CNRS UMR 8079, AgroParisTech, Orsay, France
- Department of Ecology and Evolution, Biophore, University of Lausanne, Lausanne, Switzerland
| | | | - Julie Sannier
- Université Paris-Sud, Laboratoire Ecologie, Systématique, Evolution, CNRS UMR 8079, AgroParisTech, Orsay, France
| | - Sophie Nadot
- Université Paris-Sud, Laboratoire Ecologie, Systématique, Evolution, CNRS UMR 8079, AgroParisTech, Orsay, France
| | - Catherine Damerval
- CNRS, UMR 0320/UMR 8120, Génétique Végétale, Gif-sur-Yvette, France
- * E-mail:
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Reardon W, Gallagher P, Nolan KM, Wright H, Cardeñosa-Rubio MC, Bragalini C, Lee CS, Fitzpatrick DA, Corcoran K, Wolff K, Nugent JM. Different outcomes for the MYB floral symmetry genes DIVARICATA and RADIALIS during the evolution of derived actinomorphy in Plantago. THE NEW PHYTOLOGIST 2014; 202:716-725. [PMID: 24460533 DOI: 10.1111/nph.12682] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 11/29/2013] [Indexed: 05/18/2023]
Abstract
The gene network that specifies flower shape in Antirrhinum majus (bilateral floral symmetry or zygomorphy) includes two MYB-class genes - RADIALIS (RAD) and DIVARICATA (DIV). RAD is involved in establishing the dorsal identity program and its role is to regulate the domain of activity of DIV (the ventral identity program) by restricting it to ventral regions of the flower. Plantago is in the same family as Antirrhinum but has small, radially symmetrical (actinomorphic) flowers derived from a zygomorphic ancestral state. Here we investigate the MYB-class floral symmetry genes and the role they have played in the evolution of derived actinomorphy in Plantago lanceolata. A DIV ortholog (PlDIV) but no RAD ortholog was identified in P. lanceolata. PlDIV is expressed across all petals and stamens later in flower development, which is consistent with the loss of RAD gene function. PlDIV expression in anther sporogenous tissue also suggests that PlDIV was co-opted to regulate cell proliferation during the early stages of pollen development. These results indicate that evolution of derived actinomorphy in Plantago involved complete loss of dorsal gene function, resulting in expansion of the domain of expression of the ventral class of floral symmetry genes.
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Affiliation(s)
- Wesley Reardon
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Pauline Gallagher
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Katie M Nolan
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Hayley Wright
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | | | - Claudia Bragalini
- Department of Life Sciences and Systems Biology, University of Turin, Viale Mattioli 25, 10125, Turin, Italy
| | - Chui-Sang Lee
- School of Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - David A Fitzpatrick
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Killian Corcoran
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Kirsten Wolff
- School of Biology, Newcastle University, Ridley Building, Newcastle, NE1 7RU, UK
| | - Jacqueline M Nugent
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
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Hileman LC. Bilateral flower symmetry--how, when and why? CURRENT OPINION IN PLANT BIOLOGY 2014; 17:146-52. [PMID: 24507506 DOI: 10.1016/j.pbi.2013.12.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Revised: 11/26/2013] [Accepted: 12/05/2013] [Indexed: 05/20/2023]
Abstract
Bilateral flower symmetry has evolved multiple times during flowering plant diversification, is associated with specialized pollination, and is hypothesized to have contributed to flowering plant species richness. The genes and genetic interactions that control bilateral symmetry are well understood in the model species Snapdragon (Antirrhinum majus). I review recent insights into the genetic control of symmetry in Snapdragon. I summarize how this foundational genetic work has been integrated with mathematical modeling approaches, which together provided new insights into the control of quantitative aspects of petal shape. Lastly, I review how evolutionary studies, stemming from knowledge of the genetic control of symmetry in Snapdragon flowers, have revealed extensive parallel recruitment of a similar genetic program during repeated evolution of bilateral symmetry.
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Affiliation(s)
- Lena C Hileman
- University of Kansas, Ecology and Evolutionary Biology, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA.
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Bello MA, Álvarez I, Torices R, Fuertes-Aguilar J. Floral development and evolution of capitulum structure in Anacyclus (Anthemideae, Asteraceae). ANNALS OF BOTANY 2013; 112:1597-612. [PMID: 23287557 PMCID: PMC3828941 DOI: 10.1093/aob/mcs301] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIMS Most of the diversity in the pseudanthia of Asteraceae is based on the differential symmetry and sexuality of its flowers. In Anacyclus, where there are (1) homogamous capitula, with bisexual, mainly actinomorphic and pentamerous flowers; and (2) heterogamous capitula, with peripheral zygomorphic, trimerous and long-/short-rayed female flowers, the floral ontogeny was investigated to infer their origin. METHODS Floral morphology and ontogeny were studied using scanning electron microscope and light microscope techniques. KEY RESULTS Disc flowers, subtended by paleae, initiate acropetally. Perianth and androecium initiation is unidirectional/simultaneous. Late zygomorphy occurs by enlargement of the adaxial perianth lobes. In contrast, ray flowers, subtended by involucral bracts, initiate after the proximal disc buds, breaking the inflorescence acropetal pattern. Early zygomorphy is manifested through the fusion of the lateral and abaxial perianth lobes and the arrest of the adaxials. We report atypical phenotypes with peripheral 'trumpet' flowers from natural populations. The peripheral 'trumpet' buds initiate after disc flowers, but maintain an actinomorphic perianth. All phenotypes are compared and interpreted in the context of alternative scenarios for the origin of the capitulum and the perianth identity. CONCLUSIONS Homogamous inflorescences display a uniform floral morphology and development, whereas the peripheral buds in heterogamous capitula display remarkable plasticity. Disc and ray flowers follow different floral developmental pathways. Peripheral zygomorphic flowers initiate after the proximal actinomorphic disc flowers, behaving as lateral independent units of the pseudanthial disc from inception. The perianth and the androecium are the most variable whorls across the different types of flowers, but their changes are not correlated. Lack of homology between hypanthial appendages and a calyx, and the perianth double-sided structure are discussed for Anacyclus together with potential causes of its ray flower plasticity.
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Affiliation(s)
- M. Angélica Bello
- Real Jardín Botánico, RJB-CSIC, Plaza de Murillo 2, 28014 Madrid, Spain
- For correspondence. E-mail
| | - Inés Álvarez
- Real Jardín Botánico, RJB-CSIC, Plaza de Murillo 2, 28014 Madrid, Spain
| | - Rubén Torices
- Centro de Ecologia Funcional, Universidade de Coimbra, 3001-455 Coimbra, Portugal
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Combining phylogenetic and syntenic analyses for understanding the evolution of TCP ECE genes in eudicots. PLoS One 2013; 8:e74803. [PMID: 24019982 PMCID: PMC3760840 DOI: 10.1371/journal.pone.0074803] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 08/05/2013] [Indexed: 11/24/2022] Open
Abstract
TCP ECE genes encode transcription factors which have received much attention for their repeated recruitment in the control of floral symmetry in core eudicots, and more recently in monocots. Major duplications of TCP ECE genes have been described in core eudicots, but the evolutionary history of this gene family is unknown in basal eudicots. Reconstructing the phylogeny of ECE genes in basal eudicots will help set a framework for understanding the functional evolution of these genes. TCP ECE genes were sequenced in all major lineages of basal eudicots and Gunnera which belongs to the sister clade to all other core eudicots. We show that in these lineages they have a complex evolutionary history with repeated duplications. We estimate the timing of the two major duplications already identified in the core eudicots within a timeframe before the divergence of Gunnera and after the divergence of Proteales. We also use a synteny-based approach to examine the extent to which the expansion of TCP ECE genes in diverse eudicot lineages may be due to genome-wide duplications. The three major core-eudicot specific clades share a number of collinear genes, and their common evolutionary history may have originated at the γ event. Genomic comparisons in Arabidopsis thaliana and Solanumlycopersicum highlight their separate polyploid origin, with syntenic fragments with and without TCP ECE genes showing differential gene loss and genomic rearrangements. Comparison between recently available genomes from two basal eudicots Aquilegiacoerulea and Nelumbonucifera suggests that the two TCP ECE paralogs in these species are also derived from large-scale duplications. TCP ECE loci from basal eudicots share many features with the three main core eudicot loci, and allow us to infer the makeup of the ancestral eudicot locus.
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Zhang W, Steinmann VW, Nikolov L, Kramer EM, Davis CC. Divergent genetic mechanisms underlie reversals to radial floral symmetry from diverse zygomorphic flowered ancestors. FRONTIERS IN PLANT SCIENCE 2013; 4:302. [PMID: 23970887 PMCID: PMC3747361 DOI: 10.3389/fpls.2013.00302] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 07/20/2013] [Indexed: 05/24/2023]
Abstract
Malpighiaceae possess flowers with a unique bilateral symmetry (zygomorphy), which is a hypothesized adaptation associated with specialization on neotropical oil bee pollinators. Gene expression of two representatives of the CYC2 lineage of floral symmetry TCP genes, CYC2A and CYC2B, demarcate the adaxial (dorsal) region of the flower in the characteristic zygomorphic flowers of most Malpighiaceae. Several clades within the family, however, have independently lost their specialized oil bee pollinators and reverted to radial flowers (actinomorphy) like their ancestors. Here, we investigate CYC2 expression associated with four independent reversals to actinomorphy. We demonstrate that these reversals are always associated with alteration of the highly conserved CYC2 expression pattern observed in most New World (NW) Malpighiaceae. In NW Lasiocarpus and Old World (OW) Microsteria, the expression of CYC2-like genes has expanded to include the ventral region of the corolla. Thus, the pattern of gene expression in these species has become radialized, which is comparable to what has been reported in the radial flowered legume clade Cadia. In striking contrast, in NW Psychopterys and OW Sphedamnocarpus, CYC2-like expression is entirely absent or at barely detectable levels. This is more similar to the pattern of CYC2 expression observed in radial flowered Arabidopsis. These results collectively indicate that, regardless of geographic distribution, reversals to similar floral phenotypes in this large tropical angiosperm clade have evolved via different genetic changes from an otherwise highly conserved developmental program.
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Affiliation(s)
- Wenheng Zhang
- Department of Organismic and Evolutionary Biology, Harvard University HerbariaCambridge, MA, USA
- Department of Biology, Virginia Commonwealth UniversityRichmond, VA, USA
| | | | - Lachezar Nikolov
- Department of Organismic and Evolutionary Biology, Harvard University HerbariaCambridge, MA, USA
| | - Elena M. Kramer
- Department of Organismic and Evolutionary Biology, Harvard University HerbariaCambridge, MA, USA
| | - Charles C. Davis
- Department of Organismic and Evolutionary Biology, Harvard University HerbariaCambridge, MA, USA
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Isolation and molecular characterization of thirteen R2R3-MYB transcription factors from Epimedium sagittatum. Int J Mol Sci 2012; 14:594-610. [PMID: 23271373 PMCID: PMC3565284 DOI: 10.3390/ijms14010594] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 12/11/2012] [Accepted: 12/11/2012] [Indexed: 01/07/2023] Open
Abstract
Epimedium sagittatum (Sieb. et Zucc.) Maxim, a popular traditional Chinese medicinal plant, has been widely used for treating sexual dysfunction and osteoporosis in China. The main bioactive components in herba epimedii are prenylated flavonol glycosides, which are end products of a branch of the flavonoid biosynthetic pathway. The MYB transcription factors (TF) act as activators or repressors to regulate the flavonoid pathway. In this study, 13 full-length cDNA clones of R2R3-MYB TFs from E. sagittatum (designated as EsMYB1 to EsMYB13) were isolated and characterized. Sequence similarity and phylogenetic analysis placed nine R2R3-MYB members of epimedii into five subgroups of the Arabidopsis R2R3-MYB family, while four members were not clustered into a defined subgroup. The number and length of introns from epimedii R2R3-MYB genes varied significantly, but intron positions and phases were well conserved. Expression patterns of epimedii R2R3-MYB genes in various tissues showed diverse. Finally, it is suggested that five epimedii R2R3-MYB genes may be involved in regulating the flavonoid pathway and could be used as valuable candidate genes for metabolic engineering studies in future. Sequence information of 13 R2R3-MYB genes discovered here will also provide an entry point into the overview of whole R2R3-MYB family in epimedii.
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He J, Zhou T, Irwin DM, Shen Y, Zhang Y. The Motilin Gene Evolved a New Function in Kangaroo Rats and Kangaroo Mice (Dipodomyinae). J Mol Evol 2012; 75:112-8. [DOI: 10.1007/s00239-012-9522-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 09/24/2012] [Indexed: 12/20/2022]
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Zhang W, Kramer EM, Davis CC. Similar genetic mechanisms underlie the parallel evolution of floral phenotypes. PLoS One 2012; 7:e36033. [PMID: 22558314 PMCID: PMC3338646 DOI: 10.1371/journal.pone.0036033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 03/27/2012] [Indexed: 01/17/2023] Open
Abstract
The repeated origin of similar phenotypes is invaluable for studying the underlying genetics of adaptive traits; molecular evidence, however, is lacking for most examples of such similarity. The floral morphology of neotropical Malpighiaceae is distinctive and highly conserved, especially with regard to symmetry, and is thought to result from specialization on oil-bee pollinators. We recently demonstrated that CYCLOIDEA2–like genes (CYC2A and CYC2B) are associated with the development of the stereotypical floral zygomorphy that is critical to this plant–pollinator mutualism. Here, we build on this developmental framework to characterize floral symmetry in three clades of Malpighiaceae that have independently lost their oil bee association and experienced parallel shifts in their floral morphology, especially in regard to symmetry. We show that in each case these species exhibit a loss of CYC2B function, and a strikingly similar shift in the expression of CYC2A that is coincident with their shift in floral symmetry. These results indicate that similar floral phenotypes in this large angiosperm clade have evolved via parallel genetic changes from an otherwise highly conserved developmental program.
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Affiliation(s)
- Wenheng Zhang
- Department of Organismic and Evolutionary Biology, Harvard University Herbaria, Cambridge, Massachusetts, USA
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40
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Genetic analysis of floral symmetry in Van Gogh's sunflowers reveals independent recruitment of CYCLOIDEA genes in the Asteraceae. PLoS Genet 2012; 8:e1002628. [PMID: 22479210 PMCID: PMC3315478 DOI: 10.1371/journal.pgen.1002628] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 02/02/2012] [Indexed: 12/04/2022] Open
Abstract
The genetic basis of floral symmetry is a topic of great interest because of its effect on pollinator behavior and, consequently, plant diversification. The Asteraceae, which is the largest family of flowering plants, is an ideal system in which to study this trait, as many species within the family exhibit a compound inflorescence containing both bilaterally symmetric (i.e., zygomorphic) and radially symmetric (i.e., actinomorphic) florets. In sunflower and related species, the inflorescence is composed of a single whorl of ray florets surrounding multiple whorls of disc florets. We show that in double-flowered (dbl) sunflower mutants (in which disc florets develop bilateral symmetry), such as those captured by Vincent van Gogh in his famous nineteenth-century sunflower paintings, an insertion into the promoter region of a CYCLOIDEA (CYC)-like gene (HaCYC2c) that is normally expressed specifically in WT rays is instead expressed throughout the inflorescence, presumably resulting in the observed loss of actinomorphy. This same gene is mutated in two independent tubular-rayed (tub) mutants, though these mutations involve apparently recent transposon insertions, resulting in little or no expression and radialization of the normally zygomorphic ray florets. Interestingly, a phylogenetic analysis of CYC-like genes from across the family suggests that different paralogs of this fascinating gene family have been independently recruited to specify zygomorphy in different species within the Asteraceae. The evolution of flower shape and symmetry is of great interest to plant biologists, because it can affect pollinator behavior. Species in the flowering plant family Asteraceae exhibit flower heads that can contain both bilaterally and radially symmetric flowers. In this study, we identify a CYCLOIDEA-like gene that is responsible for determining flower symmetry in sunflower. Mis-expression of this gene causes a double-flowered phenotype, similar to those captured in Vincent van Gogh's famous nineteenth-century paintings, whereas loss of gene function causes radialization of the normally bilaterally symmetric ray florets. Interestingly, this gene is not orthologous to the CYCLOIDEA-like gene responsible for floral symmetry in other members of the Asteraceae, providing evidence of the parallel recruitment of different members of the same gene family for the same function.
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Howarth DG, Martins T, Chimney E, Donoghue MJ. Diversification of CYCLOIDEA expression in the evolution of bilateral flower symmetry in Caprifoliaceae and Lonicera (Dipsacales). ANNALS OF BOTANY 2011; 107:1521-32. [PMID: 21478175 PMCID: PMC3108805 DOI: 10.1093/aob/mcr049] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 12/07/2010] [Accepted: 01/24/2011] [Indexed: 05/20/2023]
Abstract
BACKGROUND AND AIMS The expression of floral symmetry genes is examined in the CYCLOIDEA lineage following duplication, and these are linked to changes in flower morphology. The study focuses on Dipsacales, comparing DipsCYC2 gene expression in Viburnum (radially symmetrical Adoxaceae) to members of early-diverging lineages of the bilaterally symmetrical Caprifoliaceae (Diervilla and Lonicera). METHODS Floral tissue from six species, which included dorsal, lateral and ventral regions of the corolla, was dissected. RNA was extracted from these tissues and each copy of DipsCYC2 was amplified with reverse transcriptase PCR. KEY RESULTS Members of DipsCYC2 were expressed across the corolla in the radially symmetrical Viburnum plicatum. A shift to bilaterally symmetrical flowers at the base of the Caprifoliaceae was accompanied by a duplication of the DipsCYC2 gene, resulting in DipsCYC2A and DipsCYC2B, and by loss of expression of both of these copies in the ventral petal. In Lonicera (Caprifolieae), there is a shift from flowers with two dorsally and three ventrally oriented corolla lobes to a clear differentiation of dorsal, lateral and ventral lobes. This shift entailed a decoupling of expression of DipsCYC2A and DipsCYC2B; DipsCYC2B continues to be expressed in the dorsal and lateral lobes, while DipsCYC2A expression is restricted to just the two dorsal lobes. A reversion to more radially symmetrical flowers within Lonicera was accompanied by a re-expansion of expression of both DipsCYC2A and DipsCYC2B. CONCLUSIONS The transition to bilateral symmetry in Caprifoliaceae involved: (a) duplication of an ancestral DipsCYC2 gene; (b) the loss of expression of both of these copies in the ventral petal; and (c) changes in the zone of expression, with one copy continuing to be expressed across the dorsal and lateral petals, and the other copy becoming restricted in expression to the dorsal corolla lobes.
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Affiliation(s)
- Dianella G Howarth
- Department of Biological Sciences, St John's University, Jamaica, NY 11439, USA.
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Preston JC, Martinez CC, Hileman LC. Gradual disintegration of the floral symmetry gene network is implicated in the evolution of a wind-pollination syndrome. Proc Natl Acad Sci U S A 2011; 108:2343-8. [PMID: 21282634 PMCID: PMC3038713 DOI: 10.1073/pnas.1011361108] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Angiosperms exhibit staggering diversity in floral form, and evolution of floral morphology is often correlated with changes in pollination syndrome. The showy, bilaterally symmetrical flowers of the model species Antirrhinum majus (Plantaginaceae) are highly specialized for bee pollination. In A. majus, Cycloidea (CYC), Dichotoma (DICH), Radialis (RAD), and Divaricata (DIV) specify the development of floral bilateral symmetry. However, it is unclear to what extent evolution of these genes has resulted in flower morphological divergence among closely related members of Plantaginaceae differing in pollination syndrome. We compared floral symmetry genes from insect-pollinated Digitalis purpurea, which has bilaterally symmetrical flowers, with those from closely related Aragoa abietina and wind-pollinated Plantago major, both of which have radially symmetrical flowers. We demonstrate that Plantago, but not Aragoa, species have lost a dorsally expressed CYC-like gene and downstream targets RAD and DIV. Furthermore, the single P. major CYC-like gene is expressed across all regions of the flower, similar to expression of its ortholog in closely related Veronica serpyllifolia. We propose that changes in the expression of duplicated CYC-like genes led to the evolution of radial flower symmetry in Aragoa/Plantago, and that further disintegration of the symmetry gene pathway resulted in the wind-pollination syndrome of Plantago. This model underscores the potential importance of gene loss in the evolution of ecologically important traits.
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Affiliation(s)
- Jill C Preston
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA.
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Bartlett ME, Specht CD. Changes in expression pattern of the teosinte branched1-like genes in the Zingiberales provide a mechanism for evolutionary shifts in symmetry across the order. AMERICAN JOURNAL OF BOTANY 2011; 98:227-43. [PMID: 21613112 DOI: 10.3732/ajb.1000246] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
PREMISE OF THE STUDY Floral symmetry is a trait of key importance when considering floral diversification because it is thought to play a significant role in plant-pollinator interactions. The CYCLOIDEA/TEOSINTE BRANCHED1 (CYC/TB1)-like genes have been implicated in the development and evolution of floral symmetry in numerous lineages. We thus chose to investigate a possible role for these genes in the evolution of floral symmetry within petaloid monocots, using the order Zingiberales as a model system. In the Zingiberales, evolutionary shifts in symmetry have occurred in all floral whorls, making the order ideal for studying the evolution of this ecologically significant trait. METHODS We analyzed TB1-like (TBL) genes from taxa spanning the order in a phylogenetic context. Using RNA in situ hybridization, we examined the expression of two TBL genes in Costus spicatus (Costaceae) and Heliconia stricta (Heliconiaceae), taxa with divergent floral symmetry patterns. KEY RESULTS We identified Zingiberales-specific gene duplications as well as a duplication in the TBL gene lineage that predates the diversification of commelinid monocots. Shifts in TBL gene expression were associated with evolutionary shifts in floral symmetry and stamen abortion. ZinTBL1a expression was found in the posterior (adaxial) staminode of H. stricta and in the abaxial staminodial labellum of C. spicatus. ZinTBL2 expression was strongest in the anterior (abaxial) sepals of H. stricta and in the adaxial fertile stamen of C. spicatus. CONCLUSIONS This study adds to the growing body of evidence that CYC/TB1-like genes have been repeatedly recruited throughout the course of evolution to generate bilateral floral symmetry (zygomorphy).
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Affiliation(s)
- Madelaine E Bartlett
- Department of Plant and Microbial Biology, University of California Berkeley, 111 Koshland Hall, Berkeley, California 94720, USA.
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Jiang HW, Liu MJ, Chen IC, Huang CH, Chao LY, Hsieh HL. A glutathione S-transferase regulated by light and hormones participates in the modulation of Arabidopsis seedling development. PLANT PHYSIOLOGY 2010; 154:1646-58. [PMID: 20935176 PMCID: PMC2996023 DOI: 10.1104/pp.110.159152] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Accepted: 10/07/2010] [Indexed: 05/17/2023]
Abstract
Glutathione S-transferases (GSTs) have been well documented to be involved in diverse aspects of biotic and abiotic stresses, especially detoxification processes. Whether they regulate plant development remains unclear. Here, we report on our isolation by reverse transcription-polymerase chain reaction of a plant GST, AtGSTU17, from Arabidopsis (Arabidopsis thaliana) and demonstrate that its expression is regulated by multiple photoreceptors, especially phytochrome A (phyA) under all light conditions. Further physiological studies indicated that AtGSTU17 participates in various aspects of seedling development, including hypocotyl elongation, anthocyanin accumulation, and far-red light-mediated inhibition of greening with a requirement of functional phyA. The loss-of-function mutant of AtGSTU17 (atgstu17) resulted in reduced biomass of seedlings and number of lateral roots in the presence of auxin, as well as insensitivity to abscisic acid (ABA)-mediated inhibition of root elongation, with similarity to different phyA mutant alleles. Moreover, the root phenotype conferred by atgstu17 was reflected by histochemical β-glucuronidase staining of AtGSTU17 promoter activity with the addition of auxin or ABA. Further microarray analysis of wild-type Columbia and atgstu17 seedlings treated with far-red irradiation or ABA revealed that AtGSTU17 might modulate hypocotyl elongation by positively regulating some light-signaling components and negatively regulating a group of auxin-responsive genes and modulate root development by negatively controlling an auxin transport protein in the presence of ABA. Therefore, our data reveal that AtGSTU17 participates in light signaling and might modulate various aspects of Arabidopsis development by affecting glutathione pools via a coordinated regulation with phyA and phytohormones.
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Molecular cloning and expression analysis of a novel SANT/MYB gene from Gossypium barbadense. Mol Biol Rep 2010; 38:2329-36. [PMID: 21069464 DOI: 10.1007/s11033-010-0366-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2010] [Accepted: 10/28/2010] [Indexed: 10/18/2022]
Abstract
MYB family transcription factors are implicated in multiple developmental processes. Herein, a new full-length cDNA encoding a SANT/MYB transcription factor (designated as GbRL2) was cloned and characterized from cotton (Gossypium barbadense L.) for the first time. The full-length cDNA of GbRL2 was 573 bp with a 240 bp open reading frame (ORF) encoding a deduced protein of 80 amino acid polypeptide with a calculated molecular mass of 8.96 kDa and an isoelectric point of 8.96. Sequence alignment revealed that GbRL2 had high homology with other single SANT/MYB domain containing genes, including the RADIALIS genes in Antirrhinum majus and Bournea leiophylla. Semi-quantitative reverse transcript polymerase chain reaction (RT-PCR) revealed that at seedling stage, GbRL2 was strongly expressed in leaves but merely in stems. In opening flowers, the expression of GbRL2 was moderate in the petals but could not be detected in stamens. In ovules, the expression of GbRL2 could not be detected at -3 days post-anthesis (DPA) but increased during early elongation stage (0 DPA, +3 DPA, +5 DPA and +8 DPA). The transcripts of GbRL2 could also be detected at +8 DPA elongating fibers. We also examined the expression of RL2 gene in Gossypium hirstum cultivar Xu-142 and its fuzzless-lintless-seed mutant fl plants. The GhRL2 gene was ectopically expressed at -3 DPA in the fl mutant while the expression of GhRL2 in WT could not be detected. The expression of GhRL2 decreased early (+5 DPA) while that of WT was still strong. Our results suggest that GbRL2 may participate in development of various organs and may be a target for genetic improvement of cotton fiber.
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Busch A, Zachgo S. Flower symmetry evolution: towards understanding the abominable mystery of angiosperm radiation. Bioessays 2010; 31:1181-90. [PMID: 19847818 DOI: 10.1002/bies.200900081] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Flower symmetry is considered a morphological novelty that contributed significantly to the rapid radiation of the angiosperms, which already puzzled Charles Darwin and prompted him to name this phenomenon an 'abominable mystery'. In 2009, the bicentenary of Darwin's birth and the 150th anniversary of the publication of his seminal work, 'On the Origin of Species', this question can now be more satisfactorily readdressed. Understanding the molecular control of monosymmetry formation in the model species Antirrhinum opened the path for comparative studies with non-model species revealing modifications of this trait. TCP transcription factors, named after TEOSINTE BRANCHED 1 in maize, CYCLOIDEA in snapdragon and PCF in rice, control flower monosymmetry development and contributed to establishing this trait several times independently in higher angiosperms. The joint advances in evolutionary and developmental plant research, combined in the novel research field named Evo/Devo, aim at elucidating the molecular mechanisms and strategies to unravel the mystery of how this diversity has been generated.
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Affiliation(s)
- Andrea Busch
- Botany Department, University of Osnabrück, Osnabrück, Germany
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Specht CD, Bartlett ME. Flower Evolution: The Origin and Subsequent Diversification of the Angiosperm Flower. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2009. [DOI: 10.1146/annurev.ecolsys.110308.120203] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Chelsea D. Specht
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720; ,
| | - Madelaine E. Bartlett
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720; ,
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Song CF, Lin QB, Liang RH, Wang YZ. Expressions of ECE-CYC2 clade genes relating to abortion of both dorsal and ventral stamens in Opithandra (Gesneriaceae). BMC Evol Biol 2009; 9:244. [PMID: 19811633 PMCID: PMC2763874 DOI: 10.1186/1471-2148-9-244] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Accepted: 10/07/2009] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND ECE-CYC2 clade genes known in patterning floral dorsoventral asymmetry (zygomorphy) in Antirrhinum majus are conserved in the dorsal identity function including arresting the dorsal stamen. However, it remains uncertain whether the same mechanism underlies abortion of the ventral stamens, an important morphological trait related to evolution and diversification of zygomorphy in Lamiales sensu lato, a major clade of predominantly zygomorphically flowered angiosperms. Opithandra (Gesneriaceae) is of particular interests in addressing this question as it is in the base of Lamiales s.l., an early representative of this type zygomorphy. RESULTS We investigated the expression patterns of four ECE-CYC2 clade genes and two putative target cyclinD3 genes in Opithandra using RNA in situ hybridization and RT-PCR. OpdCYC gene expressions were correlated with abortion of both dorsal and ventral stamens in Opithandra, strengthened by the negatively correlated expression of their putative target OpdcyclinD3 genes. The complement of OpdcyclinD3 to OpdCYC expressions further indicated that OpdCYC expressions were related to the dorsal and ventral stamen abortion through negative effects on OpdcyclinD3 genes. CONCLUSION These results suggest that ECE-CYC2 clade TCP genes are not only functionally conserved in the dorsal stamen repression, but also involved in arresting ventral stamens, a genetic mechanism underlying the establishment of zygomorphy with abortion of both the dorsal and ventral stamens evolved in angiosperms, especially within Lamiales s.l.
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Affiliation(s)
- Chun-Feng Song
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing 100093, PR China.
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Howarth DG, Donoghue MJ. Duplications and expression of DIVARICATA-like genes in dipsacales. Mol Biol Evol 2009; 26:1245-58. [PMID: 19289599 DOI: 10.1093/molbev/msp051] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The genetics underlying flower symmetry shifts between radial and bilateral symmetry has been intensively studied in the model Antirrhinum majus. Understanding the conservation or diversification of this genetic pathway in other plants is of special interest in understanding angiosperm evolution and ecology. Evidence from Antirrhinum indicates that TCP and MYB transcription factors, especially CYCLOIDEA (CYC), DICHOTOMA (DICH), DIVARICATA (DIV), and RADIALIS (RAD) play a role in specifying dorsal identity (CYC, DICH, and RAD) and ventral identity (DIV) in the corolla and androecium of monosymmetric (bilateral) flowers. Previous data indicate that the ECE clade of TCP genes (including CYC and DICH) underwent two duplication events around the diversification of the core eudicots. In this study, we examined the duplication events within Dipsacales, which contains both radially and bilaterally symmetrical flowered species. Additionally, we report here the phylogenetic relationships of the DIV-like genes across core eudicots. Like TCP genes, we found three core eudicot clades of DIV-like genes, with duplications occurring around the diversification of the core eudicots, which we name DIV1, DIV2, and DIV3. The Antirrhinum genes, DIVARICATA and its sister DVL1, fall into the DIV1 clade. We also found additional duplications within these clades in Dipsacales. Specifically, the Caprifoliaceae (bilaterally symmetrical clade) duplicated independently in each of the three core eudicot DIV clades. Using reverse transcription polymerase chain reaction (rtPCR), we showed that most of these copies are expressed across floral tissues in the Dipsacales species Heptacodium miconioides. One copy, DipsDIV1A (orthologous to DIV and DVL1), was expressed in a dorsal-ventral pattern. DipsDIV1A was expressed only in petal tissue, in both dorsal and ventral regions but was lacking from lateral petals. We argue that this suggests that DipsDIV1A may be expressed in a similar pattern to DIV in Antirrhinum, suggesting a broad conservation of this pathway. Finally, DIV contains a large intron near the beginning of the second MYB domain, which shows promise as a highly variable molecular marker for phylogenetic studies.
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Affiliation(s)
- Dianella G Howarth
- Department of Biological Sciences, St. John's University, Queens, NY, USA.
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Preston JC, Hileman LC. Developmental genetics of floral symmetry evolution. TRENDS IN PLANT SCIENCE 2009; 14:147-54. [PMID: 19231272 DOI: 10.1016/j.tplants.2008.12.005] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 12/10/2008] [Accepted: 12/17/2008] [Indexed: 05/04/2023]
Abstract
The relative importance of convergence and parallelism in the independent evolution of similar traits remains an important question in evolutionary biology. Floral zygomorphy has evolved multiple times independently in different plant lineages through alterations in size, shape and/or number of spatially defined organs. In Antirrhinum majus (snapdragon) floral zygomorphy is controlled by CYCLOIDEA and DICHOTOMA, two recently duplicated TCP transcription factors that determine dorsal identity through their interaction with MYB and cell-cycle genes. Early on it was speculated that independent evolutionary transitions from floral actinomorphy to zygomorphy would probably result from unique developmental genetic mechanisms. Here, we review recent evidence supporting the parallel recruitment of CYCLOIDEA homologs in independent evolutionary transitions to zygomorphy in distantly related core eudicot lineages.
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Affiliation(s)
- Jill C Preston
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA
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