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Zhang G, Yang J, Zhang C, Jiao B, Panero JL, Cai J, Zhang ZR, Gao LM, Gao T, Ma H. Nuclear phylogenomics of Asteraceae with increased sampling provides new insights into convergent morphological and molecular evolution. Plant Commun 2024:100851. [PMID: 38409784 DOI: 10.1016/j.xplc.2024.100851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 01/22/2024] [Accepted: 02/21/2024] [Indexed: 02/28/2024]
Abstract
Convergent morphological evolution is widespread in flowering plants, and understanding this phenomenon relies on well-resolved phylogenies. Nuclear phylogenetic reconstruction using transcriptome datasets has been successful in various angiosperm groups, but it is limited to taxa with available fresh materials. Asteraceae, which are one of the two largest angiosperm families and are important for both ecosystems and human livelihood, show multiple examples of convergent evolution. Nuclear Asteraceae phylogenies have resolved relationships among most subfamilies and many tribes, but many phylogenetic and evolutionary questions regarding subtribes and genera remain, owing to limited sampling. Here, we increased the sampling for Asteraceae phylogenetic reconstruction using transcriptomes and genome-skimming datasets and produced nuclear phylogenetic trees with 706 species representing two-thirds of recognized subtribes. Ancestral character reconstruction supports multiple convergent evolutionary events in Asteraceae, with gains and losses of bilateral floral symmetry correlated with diversification of some subfamilies and smaller groups, respectively. Presence of the calyx-related pappus may have been especially important for the success of some subtribes and genera. Molecular evolutionary analyses support the likely contribution of duplications of MADS-box and TCP floral regulatory genes to innovations in floral morphology, including capitulum inflorescences and bilaterally symmetric flowers, potentially promoting the diversification of Asteraceae. Subsequent divergences and reductions in CYC2 gene expression are related to the gain and loss of zygomorphic flowers. This phylogenomic work with greater taxon sampling through inclusion of genome-skimming datasets reveals the feasibility of expanded evolutionary analyses using DNA samples for understanding convergent evolution.
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Affiliation(s)
- Guojin Zhang
- College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, China; Department of Biology, the Huck Institute of the Life Sciences, the Pennsylvania State University, State College, PA 16801, USA; State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Junbo Yang
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Caifei Zhang
- Wuhan Botanical Garden and Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan 430074, China
| | - Bohan Jiao
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - José L Panero
- Department of Integrative Biology, University of Texas, Austin, TX 78712, USA
| | - Jie Cai
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Zhi-Rong Zhang
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China
| | - Lian-Ming Gao
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China; Lijiang National Forest Biodiversity National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang, Yunnan 674100, China.
| | - Tiangang Gao
- State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
| | - Hong Ma
- Department of Biology, the Huck Institute of the Life Sciences, the Pennsylvania State University, State College, PA 16801, USA.
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2
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Zhang T. Symmetry vs coloration in flowers: a tight genetic link through evolutionary co-option. New Phytol 2022; 236:800-802. [PMID: 35947532 DOI: 10.1111/nph.18402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- Teng Zhang
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, 00014, Helsinki, Finland
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3
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Nevard L, Vallejo‐Marín M. Floral orientation affects outcross-pollen deposition in buzz-pollinated flowers with bilateral symmetry. Am J Bot 2022; 109:1568-1578. [PMID: 36193950 PMCID: PMC9828177 DOI: 10.1002/ajb2.16078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 05/28/2023]
Abstract
PREMISE Floral orientation is central to plant-pollinator interactions and is commonly associated with floral symmetry. Bilaterally symmetrical flowers are often oriented horizontally for optimal pollinator positioning and pollen transfer efficiency, while the orientation of radially symmetrical flowers is variable. Buzz-pollinated species (pollinated by vibration-producing bees) include bilateral, horizontally oriented flowers, and radial, pendant flowers. The effect of floral orientation on pollen transfer has never been tested in buzz-pollinated species. METHODS Here, we examined the effect of floral orientation on bumblebee-mediated pollen deposition in three buzz-pollinated Solanum species with different floral symmetry and natural orientations: S. lycopersicum and S. seaforthianum (radial, pendant), and S. rostratum (bilateral, horizontal). We tested whether orientation affects total stigmatic pollen deposition (both self and outcross pollen) when all flowers have the same orientation (either pendant or horizontal). In a second experiment, we evaluated whether different orientations of donor and recipient flowers affects the receipt of outcross pollen by S. rostratum. RESULTS For the three Solanum species studied, there was no effect of floral orientation on total pollen deposition (both self and outcross) when flowers shared the same orientation. In contrast, in our experiment with S. rostratum, we found that pendant flowers received fewer outcross-pollen grains when paired with pendant donors. CONCLUSIONS We suggest that floral orientation influences the quality of pollen transferred, with more outcross pollen transferred to horizontally oriented recipients in the bilaterally symmetrical S. rostratum. Whether other bilaterally symmetrical, buzz-pollinated flowers also benefit from increased cross-pollination when presented horizontally remains to be established.
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Affiliation(s)
- Lucy Nevard
- Biological & Environmental SciencesUniversity of StirlingStirlingUKFK9 4LA
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Yu Q, Zhao T, Zhao H, Specht CD, Tian X, Liao J. Correlation between Inflorescence Architecture and Floral Asymmetry-Evidence from Aberrant Flowers in Canna L. (Cannaceae). Plants (Basel) 2022; 11:2512. [PMID: 36235378 PMCID: PMC9571657 DOI: 10.3390/plants11192512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Floral symmetry studies often focus on the development of monosymmetric and polysymmetric flowers, whereas asymmetric flowers and their position and function within the inflorescence structure are largely neglected. Cannaceae is one of the few families that possesses truly asymmetric flowers, serving as a model to study the characters and mechanisms involved in the development of floral asymmetry and its context within the developing and mature inflorescence. In this study, inflorescence structure and floral morphology of normal asymmetric flowers and 16 aberrant flower collections from Canna indica L. and C. glauca L. were photographed, analyzed, and compared with attention to stamen petaloidy, floral symmetry, and inflorescence branching patterns anterior and posterior to the aberrant flower. In comparison with normal flowers, the aberrant flowers are arranged into abnormal partial florescences, and vary in floral symmetry, orientation, and degree of androecial petaloidy. The appendage of the fertile stamen is universally located distal from the higher order bract, indicating an underlying influence of inflorescence architecture. A synthetic model is proposed to explain the relationship between floral symmetry and inflorescence structure. Data from the observation of aberrant phenotypes strongly support the hypothesis that irregular petaloidy of the stamens is correlated with an asymmetric morphogenetic field within the inflorescence that contributes to the overall floral asymmetry in Canna flowers.
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Affiliation(s)
- Qianxia Yu
- Department of Grassland Science, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Tong Zhao
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Guangdong Eco-Engineering Polytechnic, Guangzhou 510520, China
| | - Haichan Zhao
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Guangdong Yunfu Vocational College of Chinese Medicine, Yunfu 527400, China
| | - Chelsea D. Specht
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY 14853, USA
| | - Xueyi Tian
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Foshan Institute of Forestry, Foshan 528222, China
| | - Jingping Liao
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
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5
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Armbruster WS. Floral specialization increases pollination precision: the roles of floral orientation, symmetry, fusion and stamen number. New Phytol 2022; 235:1307-1309. [PMID: 35621012 DOI: 10.1111/nph.18215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- W Scott Armbruster
- School of Biological Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
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6
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Stewart AB, Diller C, Dudash MR, Fenster CB. Pollination-precision hypothesis: support from native honey bees and nectar bats. New Phytol 2022; 235:1629-1640. [PMID: 35194792 DOI: 10.1111/nph.18050] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 02/09/2022] [Indexed: 05/28/2023]
Abstract
The evolution of floral traits is often considered to reflect selection for increased pollination efficiency. Known as the pollination-precision hypothesis, increased pollination efficiency is achieved by enhancing pollen deposition on precise areas of the pollinator. Most research to date addressing this hypothesis has examined plant species that are a priori predicted to place pollen precisely, but we still lack comparisons with species predicted to have low pollination efficiency. We studied 39 plant species with diverse floral morphologies and measured the precision of pollen placement on two pollinator groups: honey bees (genus Apis) and nectar bats (family Pteropodidae). Pollen was collected from four locations of each pollinator's body (bees: dorsal thorax, ventral thorax, dorsal abdomen, ventral abdomen; bats: crown, face, chest, wing) to calculate pollen placement precision using Pielou's evenness index. We also quantified variation in floral design by scoring floral symmetry, corolla fusion, floral orientation and stamen number. We confirm the importance of four floral character states (bilateral symmetry, fused corollas, horizontal orientation and reduced stamen number) in promoting precise pollen placement on diverse pollinators. Our findings provide phylogenetically corrected, empirical support that the evolution of the four floral characters reflect selection for enhanced precision of pollen placed on pollinators.
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Affiliation(s)
- Alyssa B Stewart
- Department of Plant Science, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Carolina Diller
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, 234 56, Sweden
| | - Michele R Dudash
- Department of Natural Resource Management, South Dakota State University, Brookings, SD, 57007, USA
- Department of Biology, University of Maryland, College Park, MD, 20742, USA
| | - Charles B Fenster
- Oak Lake Field Station, South Dakota State University, Brookings, SD, 57007, USA
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7
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Zhang J, Stevens PF, Zhang W. Evolution and development of inflorescences and floral symmetry in Solanaceae. Am J Bot 2022; 109:746-767. [PMID: 35619567 PMCID: PMC9324824 DOI: 10.1002/ajb2.1864] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 03/12/2022] [Accepted: 03/14/2022] [Indexed: 05/16/2023]
Abstract
PREMISE The inflorescences of Solanaceae are unique and complex, which has led to long-standing disputes over floral symmetry mainly due to different interpretations of the cyme-like inflorescence structure. The main disagreements have been over how the phyllomes associated with the flower were arranged relative to the inflorescence axis especially during early flower initiation. METHODS Here we investigated the evolution of inflorescences in Solanaceae by analyzing inflorescence structure in the context of phylogeny using ancestral state reconstruction (ASR) to determine the evolutionary transitions between loosely arranged and tightly clustered inflorescences and between monochasial-like and dichasial-like cymes. We also reconstructed two- and three-dimensional models for 12 solanaceous species that represent both inflorescence and phylogenetic diversity in the family. RESULTS Our results indicate that the most recent common ancestor of Solanaceae had a loosely arranged and monochasial-like cyme, while tightly clustered inflorescences and dichasial-like cymes were derived. Compared to the known process of scorpioid cyme evolution, Solanaceae achieved their scorpioid cyme-like inflorescences through a previously undescribed way. Along the pedicel, the two flower-preceding prophylls are not in the typical transverse position of dicotyledonous plants; they frequently have axillary buds, and the main inflorescence axis continues in a sympodial fashion. As a result, the plane of symmetry of the flower is 36° from the median, and the inflorescence axis and the two flower-preceding prophylls are symmetrically located along that plane. CONCLUSIONS A better understanding of the morphological evolution of solanaceous inflorescence structure helped clarify the floral symmetry of Solanaceae.
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Affiliation(s)
- Jingbo Zhang
- Department of BiologyVirginia Commonwealth University1000 West Cary StreetRichmondVA23284USA
- Present address:
Department of Biological SciencesSt. John's University, 8000 Utopia ParkwayQueensNY11790USA
| | - Peter F. Stevens
- Department of BiologyUniversity of Missouri‐St. Louis1 University BoulevardSt. LouisMO63121USA
| | - Wenheng Zhang
- Department of BiologyVirginia Commonwealth University1000 West Cary StreetRichmondVA23284USA
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8
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Pan ZJ, Nien YC, Shih YA, Chen TY, Lin WD, Kuo WH, Hsu HC, Tu SL, Chen JC, Wang CN. Transcriptomic Analysis Suggests Auxin Regulation in Dorsal-Ventral Petal Asymmetry of Wild Progenitor Sinningia speciosa. Int J Mol Sci 2022; 23:2073. [PMID: 35216188 PMCID: PMC8876764 DOI: 10.3390/ijms23042073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/22/2022] [Accepted: 02/11/2022] [Indexed: 01/27/2023] Open
Abstract
The establishment of dorsal-ventral (DV) petal asymmetry is accompanied by differential growth of DV petal size, shape, and color differences, which enhance ornamental values. Genes involved in flower symmetry in Sinningia speciosa have been identified as CYCLOIDEA (SsCYC), but which gene regulatory network (GRN) is associated with SsCYC to establish DV petal asymmetry is still unknown. To uncover the GRN of DV petal asymmetry, we identified 630 DV differentially expressed genes (DV-DEGs) from the RNA-Seq of dorsal and ventral petals in the wild progenitor, S. speciosa 'ES'. Validated by qRT-PCR, genes in the auxin signaling transduction pathway, SsCYC, and a major regulator of anthocyanin biosynthesis were upregulated in dorsal petals. These genes correlated with a higher endogenous auxin level in dorsal petals, with longer tube length growth through cell expansion and a purple dorsal color. Over-expression of SsCYC in Nicotiana reduced petal size by regulating cell growth, suggesting that SsCYC also controls cell expansion. This suggests that auxin and SsCYC both regulate DV petal asymmetry. Transiently over-expressed SsCYC, however, could not activate most major auxin signaling genes, suggesting that SsCYC may not trigger auxin regulation. Whether auxin can activate SsCYC or whether they act independently to regulate DV petal asymmetry remains to be explored in the future.
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Affiliation(s)
- Zhao-Jun Pan
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan; (Z.-J.P.); (Y.-C.N.); (Y.-A.S.); (T.-Y.C.)
| | - Ya-Chi Nien
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan; (Z.-J.P.); (Y.-C.N.); (Y.-A.S.); (T.-Y.C.)
| | - Yu-An Shih
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan; (Z.-J.P.); (Y.-C.N.); (Y.-A.S.); (T.-Y.C.)
| | - Tsun-Ying Chen
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan; (Z.-J.P.); (Y.-C.N.); (Y.-A.S.); (T.-Y.C.)
| | - Wen-Dar Lin
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (W.-D.L.); (S.-L.T.)
| | - Wen-Hsi Kuo
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 10617, Taiwan; (W.-H.K.); (H.-C.H.)
| | - Hao-Chun Hsu
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 10617, Taiwan; (W.-H.K.); (H.-C.H.)
| | - Shih-Long Tu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (W.-D.L.); (S.-L.T.)
| | - Jen-Chih Chen
- Institute of Biotechnology, National Taiwan University, Taipei 10617, Taiwan
| | - Chun-Neng Wang
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan; (Z.-J.P.); (Y.-C.N.); (Y.-A.S.); (T.-Y.C.)
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei 10617, Taiwan; (W.-H.K.); (H.-C.H.)
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9
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Tian X, Li X, Yu Q, Zhao H, Liao J. Asymmetric expression patterns of B- and C-class MADS-box genes correspond to the asymmetrically specified androecial identities of Canna indica. Plant Biol (Stuttg) 2021; 23:540-545. [PMID: 33342001 DOI: 10.1111/plb.13231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 12/04/2020] [Indexed: 06/12/2023]
Abstract
Canna indica is a common ornamental plant with asymmetric flowers having colourful petaloid staminodes. The only fertile stamen comprises a one-theca anther and a petaloid appendage and represents the lowest stamen number in the order Zingiberales. The molecular mechanism for the asymmetric androecial petaloidy remains poorly understood. Here, we studied the identity specification in Canna stamen. We observed four types of abnormal flower in terms of androecium identity transformation and analysed the corresponding floral symmetry changes. We further tested the expression patterns of B- and C-class MADS-box genes using in situ hybridization in normal Canna stamen. Homeotic conversions in the androecium were accompanied by floral symmetry changes, and the asymmetric stamen is key in contributing to the floral asymmetry. Both B- and C-class genes exhibited higher expression levels in the anther primordium than in other androecial parts. This asymmetric expression pattern precisely corresponded to the asymmetric identities of the Canna androecium. We identified C. indica as a model species for studying androecial organ identity and floral symmetry synthetically in Zingiberales. We hypothesized that homeotic genes specify floral organ identity in a putative dose-dependent manner. The results add to the current understanding of organ identity-related floral symmetry.
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Affiliation(s)
- X Tian
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - X Li
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Q Yu
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - H Zhao
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Xinxing Vocational School of Traditional Chinese Medicine, Xinxing, Guangdong, China
| | - J Liao
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China
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10
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Joly S, Schoen DJ. Repeated evolution of a reproductive polyphenism in plants is strongly associated with bilateral flower symmetry. Curr Biol 2021; 31:1515-1520.e3. [PMID: 33539770 DOI: 10.1016/j.cub.2021.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 11/03/2020] [Accepted: 01/06/2021] [Indexed: 11/20/2022]
Abstract
Polyphenisms are a special type of phenotypic plasticity in which the products of development are not continuous but instead are separate and distinct phenotypes produced in the same genetic background. One of the most widespread polyphenisms in the flowering plants is cleistogamy, in which the same individual plant produces both open, cross-pollinated flowers as well as highly reduced and closed, self-pollinated (cleistogamous) flowers.1-5 Cleistogamy is not a rare evolutionary phenomenon. It has evolved independently at least 41 times.1 But what favors the evolution of cleistogamy is still largely unknown.1 Darwin6 proposed a hypothesis that has never been properly tested. He observed that cleistogamy is more common in taxa with bilaterally symmetric (zygomorphic) flowers than in those with radially symmetric (actinomorphic) flowers. Moreover, Darwin suggested that cleistogamous flowers help to ensure pollination, which he postulated is less certain in zygomorphic taxa that rely on more specialized groups of pollinators. Here, we combined the largest datasets on floral symmetry and cleistogamy and used phylogenetic approaches to show that cleistogamy is indeed disproportionately associated with zygomorphic flowers and that zygomorphic species are more likely to evolve cleistogamy than actinomorphic species. We also show that zygomorphic species are less capable of autonomous open-flower self-pollination (lower autofertility), suggesting that selection of cleistogamy via reproductive assurance in zygomorphic taxa could help account for Darwin's observation. Our results provide support for the hypothesis that polyphenisms are favored when organisms encounter contrasting environments.
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11
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Ruchisansakun S, Mertens A, Janssens SB, Smets EF, van der Niet T. Evolution of pollination syndromes and corolla symmetry in Balsaminaceae reconstructed using phylogenetic comparative analyses. Ann Bot 2021; 127:267-280. [PMID: 33091107 PMCID: PMC7789113 DOI: 10.1093/aob/mcaa184] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND AIMS Floral diversity as a result of plant-pollinator interactions can evolve by two distinct processes: shifts between pollination systems or divergent use of the same pollinator. Although both are pollinator driven, the mode, relative importance and interdependence of these different processes are rarely studied simultaneously. Here we apply a phylogenetic approach using the Balsaminaceae (including the species-rich genus Impatiens) to simultaneously quantify shifts in pollination syndromes (as inferred from the shape and colour of the perianth), as well as divergent use of the same pollinator (inferred from corolla symmetry). METHODS For 282 species we coded pollination syndromes based on associations between floral traits and known pollination systems, and assessed corolla symmetry. The evolution of these traits was reconstructed using parsimony- and model-based approaches, using phylogenetic trees derived from phylogenetic analyses of nuclear ribosomal and plastid DNA sequence data. KEY RESULTS A total of 71 % of studied species have a bee pollination syndrome, 22 % a bimodal syndrome (Lepidoptera and bees), 3 % a bird pollination syndrome and 5 % a syndrome of autogamy, while 19 % of species have an asymmetrical corolla. Although floral symmetry and pollination syndromes are both evolutionarily labile, the latter shifts more frequently. Shifts in floral symmetry occurred mainly in the direction towards asymmetry, but there was considerable uncertainty in the pattern of shift direction for pollination syndrome. Shifts towards asymmetrical flowers were associated with a bee pollination syndrome. CONCLUSION Floral evolution in Impatiens has occurred through both pollination syndrome shifts and divergent use of the same pollinator. Although the former appears more frequent, the latter is likely to be underestimated. Shifts in floral symmetry and pollination syndromes depend on each other but also partly on the region in which these shifts take place, suggesting that the occurrence of pollinator-driven evolution may be determined by the availability of pollinator species at large geographical scales.
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Affiliation(s)
- Saroj Ruchisansakun
- Naturalis Biodiversity Center, RA Leiden, The Netherlands
- Institute of Biology Leiden, Leiden University, Sylviusweg, BE Leiden, The Netherlands
- Department of Plant Science, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Arne Mertens
- Meise Botanic Garden, Nieuwelaan, Meise, Belgium
- Department of Biosystems, Lab of Tropical Crop Improvement, KU Leuven, Willem de Croylaan, Heverlee, Belgium
| | - Steven B Janssens
- Meise Botanic Garden, Nieuwelaan, Meise, Belgium
- Ecology, Evolution and Biodiversity Conservation, KU Leuven, Kasteelpark Arenberg, Heverlee, Belgium
| | - Erik F Smets
- Naturalis Biodiversity Center, RA Leiden, The Netherlands
- Institute of Biology Leiden, Leiden University, Sylviusweg, BE Leiden, The Netherlands
- Ecology, Evolution and Biodiversity Conservation, KU Leuven, Kasteelpark Arenberg, Heverlee, Belgium
| | - Timotheüs van der Niet
- Naturalis Biodiversity Center, RA Leiden, The Netherlands
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu–Natal, Scottsville, South Africa
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12
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Pabón-Mora N, Madrigal Y, Alzate JF, Ambrose BA, Ferrándiz C, Wanke S, Neinhuis C, González F. Evolution of Class II TCP genes in perianth bearing Piperales and their contribution to the bilateral calyx in Aristolochia. New Phytol 2020; 228:752-769. [PMID: 32491205 DOI: 10.1111/nph.16719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 05/20/2020] [Indexed: 05/21/2023]
Abstract
Controlled spatiotemporal cell division and expansion are responsible for floral bilateral symmetry. Genetic studies have pointed to class II TCP genes as major regulators of cell division and floral patterning in model core eudicots. Here we study their evolution in perianth-bearing Piperales and their expression in Aristolochia, a rare occurrence of bilateral perianth outside eudicots and monocots. The evolution of class II TCP genes reveals single-copy CYCLOIDEA-like genes and three paralogs of CINCINNATA (CIN) in early diverging angiosperms. All class II TCP genes have independently duplicated in Aristolochia subgenus Siphisia. Also CIN2 genes duplicated before the diversification of Saruma and Asarum. Sequence analysis shows that CIN1 and CIN3 share motifs with Cyclin proteins and CIN2 genes have lost the miRNA319a binding site. Expression analyses of all paralogs of class II TCP genes in Aristolochia fimbriata point to a role of CYC and CIN genes in maintaining differential perianth expansion during mid- and late flower developmental stages by promoting cell division in the distal and ventral portion of the limb. It is likely that class II TCP genes also contribute to cell division in the leaf, the gynoecium and the ovules in A. fimbriata.
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Affiliation(s)
- Natalia Pabón-Mora
- Instituto de Biología, Universidad de Antioquia, Medellín, 050010, Colombia
- Technische Universität Dresden, Institut für Botanik, Dresden, 01062, Germany
| | - Yesenia Madrigal
- Instituto de Biología, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Juan F Alzate
- Facultad de Medicina, Universidad de Antioquia, Medellín, 050010, Colombia
| | | | - Cristina Ferrándiz
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas - Universitat Politècnica de València, Valencia, 46022, Spain
| | - Stefan Wanke
- Technische Universität Dresden, Institut für Botanik, Dresden, 01062, Germany
| | - Christoph Neinhuis
- Technische Universität Dresden, Institut für Botanik, Dresden, 01062, Germany
| | - Favio González
- Facultad de Ciencias, Universidad Nacional de Colombia, Bogotá, 111321, Colombia
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LoPresti EF, Goidell J, Mola JM, Page ML, Specht CD, Stuligross C, Weber MG, Williams NM, Karban R. A lever action hypothesis for pendulous hummingbird flowers: experimental evidence from a columbine. Ann Bot 2020; 125:59-65. [PMID: 31402377 PMCID: PMC6948206 DOI: 10.1093/aob/mcz134] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 07/15/2019] [Accepted: 08/01/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND AIMS Pendulous flowers (due to a flexible pedicel) are a common, convergent trait of hummingbird-pollinated flowers. However, the role of flexible pedicels remains uncertain despite several functional hypotheses. Here we present and test the 'lever action hypothesis': flexible pedicels allow pendulous flowers to move upwards from all sides, pushing the stigma and anthers against the underside of the feeding hummingbird regardless of which nectary is being visited. METHODS To test whether this lever action increased pollination success, we wired emasculated flowers of serpentine columbine, Aquilegia eximia, to prevent levering and compared pollination success of immobilized flowers with emasculated unwired and wire controls. KEY RESULTS Seed set was significantly lower in wire-immobilized flowers than unwired control and wire control flowers. Video analysis of visits to wire-immobilized and unwired flowers demonstrated that birds contacted the stigmas and anthers of immobilized flowers less often than those of flowers with flexible pedicels. CONCLUSIONS We conclude that flexible pedicels permit the levering of reproductive structures onto a hovering bird. Hummingbirds, as uniquely large, hovering pollinators, differ from flies or bees which are too small to cause levering of flowers while hovering. Thus, flexible pedicels may be an adaptation to hummingbird pollination, in particular due to hummingbird size. We further speculate that this mechanism is effective only in radially symmetric flowers; in contrast, zygomorphic hummingbird-pollinated flowers are usually more or less horizontally oriented rather than having pendulous flowers and flexible pedicels.
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Affiliation(s)
- E F LoPresti
- Department of Plant Sciences, Michigan State University, East Lansing, MI, USA
- Department of Entomology, UC-Davis, Davis, CA, USA
| | - J Goidell
- Department of Entomology, UC-Davis, Davis, CA, USA
| | - J M Mola
- Department of Entomology, UC-Davis, Davis, CA, USA
| | - M L Page
- Department of Entomology, UC-Davis, Davis, CA, USA
| | - C D Specht
- School of Integrative Plant Sciences, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, USA
| | - C Stuligross
- Department of Entomology, UC-Davis, Davis, CA, USA
| | - M G Weber
- Department of Plant Sciences, Michigan State University, East Lansing, MI, USA
| | - N M Williams
- Department of Entomology, UC-Davis, Davis, CA, USA
| | - R Karban
- Department of Entomology, UC-Davis, Davis, CA, USA
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14
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Madrigal Y, Alzate JF, González F, Pabón-Mora N. Evolution of RADIALIS and DIVARICATA gene lineages in flowering plants with an expanded sampling in non-core eudicots. Am J Bot 2019; 106:334-351. [PMID: 30845367 DOI: 10.1002/ajb2.1243] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 12/07/2018] [Indexed: 05/18/2023]
Abstract
PREMISE OF THE STUDY Bilateral symmetry in core eudicot flowers is established by the differential expression of CYCLOIDEA (CYC), DICHOTOMA (DICH), and RADIALIS (RAD), which are restricted to the dorsal portion of the flower, and DIVARICATA (DIV), restricted to the ventral and lateral petals. Little is known regarding the evolution of these gene lineages in non-core eudicots, and there are no reports on gene expression that can be used to assess whether the network predates the diversification of core eudicots. METHODS Homologs of the RAD and DIV lineages were isolated from available genomes and transcriptomes, including those of three selected non-core eudicot species, the magnoliid Aristolochia fimbriata and the monocots Cattleya trianae and Hypoxis decumbens. Phylogenetic analyses for each gene lineage were performed. RT-PCR was used to evaluate the expression and putative contribution to floral symmetry in dissected floral organs of the selected species. KEY RESULTS RAD-like genes have undergone at least two duplication events before eudicot diversification, three before monocots and at least four in Orchidaceae. DIV-like genes also duplicated twice before eudicot diversification and underwent independent duplications specific to Orchidaceae. RAD-like and DIV-like genes have differential dorsiventral expression only in C. trianae, which contrasts with the homogeneous expression in the perianth of A. fimbriata. CONCLUSIONS Our results point to a common genetic regulatory network for floral symmetry in monocots and core eudicots, while alternative genetic mechanisms are likely driving the bilateral perianth symmetry in the early-diverging angiosperm Aristolochia.
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Affiliation(s)
- Yesenia Madrigal
- Instituto de Biología, Universidad de Antioquia, AA 1226, Cl. 67 No. 53-108, Medellín, Colombia
| | - Juan Fernando Alzate
- Centro Nacional de Secuenciación Genómica, SIU, Facultad de Medicina, Universidad de Antioquia, Cl. 70 No. 52-21, Medellín, Colombia
| | - Favio González
- Universidad Nacional de Colombia, Facultad de Ciencias, Instituto de Ciencias Naturales, AA. 7495, Bogotá, Colombia
| | - Natalia Pabón-Mora
- Instituto de Biología, Universidad de Antioquia, AA 1226, Cl. 67 No. 53-108, Medellín, Colombia
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15
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Damerval C, Citerne H, Conde e Silva N, Deveaux Y, Delannoy E, Joets J, Simonnet F, Staedler Y, Schönenberger J, Yansouni J, Le Guilloux M, Sauquet H, Nadot S. Unraveling the Developmental and Genetic Mechanisms Underpinning Floral Architecture in Proteaceae. Front Plant Sci 2019; 10:18. [PMID: 30740117 PMCID: PMC6357683 DOI: 10.3389/fpls.2019.00018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 01/08/2019] [Indexed: 05/30/2023]
Abstract
Proteaceae are a basal eudicot family with a highly conserved floral groundplan but which displays considerable variation in other aspects of floral and inflorescence morphology. Their morphological diversity and phylogenetic position make them good candidates for understanding the evolution of floral architecture, in particular the question of the homology of the undifferentiated perianth with the differentiated perianth of core eudicots, and the mechanisms underlying the repeated evolution of zygomorphy. In this paper, we combine a morphological approach to explore floral ontogenesis and a transcriptomic approach to access the genes involved in floral organ identity and development, focusing on Grevillea juniperina, a species from subfamily Grevilleoideae. We present developmental data for Grevillea juniperina and three additional species that differ in their floral symmetry using stereomicroscopy, SEM and High Resolution X-Ray Computed Tomography. We find that the adnation of stamens to tepals takes place at early developmental stages, and that the establishment of bilateral symmetry coincides with the asymmetrical growth of the single carpel. To set a framework for understanding the genetic basis of floral development in Proteaceae, we generated and annotated de novo a reference leaf/flower transcriptome from Grevillea juniperina. We found Grevillea homologs of all lineages of MADS-box genes involved in floral organ identity. Using Arabidopsis thaliana gene expression data as a reference, we found homologs of other genes involved in floral development in the transcriptome of G. juniperina. We also found at least 21 class I and class II TCP genes, a gene family involved in the regulation of growth processes, including floral symmetry. The expression patterns of a set of floral genes obtained from the transcriptome were characterized during floral development to assess their organ specificity and asymmetry of expression.
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Affiliation(s)
- Catherine Damerval
- GQE-Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Hélène Citerne
- GQE-Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Natalia Conde e Silva
- GQE-Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Yves Deveaux
- GQE-Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Etienne Delannoy
- Institute of Plant Sciences Paris-Saclay, CNRS, INRA, Universités Paris Diderot, Paris-Sud, Evry, Paris-Saclay, Gif-sur-Yvette, France
| | - Johann Joets
- GQE-Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Franck Simonnet
- GQE-Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, France
- Ecologie Systématique Evolution, AgroParisTech, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Orsay, France
| | - Yannick Staedler
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | - Jennifer Yansouni
- Institute of Plant Sciences Paris-Saclay, CNRS, INRA, Universités Paris Diderot, Paris-Sud, Evry, Paris-Saclay, Gif-sur-Yvette, France
| | - Martine Le Guilloux
- GQE-Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Hervé Sauquet
- Ecologie Systématique Evolution, AgroParisTech, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Orsay, France
- National Herbarium of New South Wales (NSW), Royal Botanic Gardens and Domain Trust, Sydney, NSW, Australia
| | - Sophie Nadot
- Ecologie Systématique Evolution, AgroParisTech, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Orsay, France
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16
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Fambrini M, Bellanca M, Costa Muñoz M, Usai G, Cavallini A, Pugliesi C. Ligulate inflorescence of Helianthus × multiflorus, cv. Soleil d'Or, correlates with a mis-regulation of a CYCLOIDEA gene characterised by insertion of a transposable element. Plant Biol (Stuttg) 2018; 20:956-967. [PMID: 30022587 DOI: 10.1111/plb.12876] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 07/13/2018] [Indexed: 06/08/2023]
Abstract
Members of CYCLOIDEA (CYC)/TEOSINTE BRANCHED1 (TB1) transcription factor family are essential to control flower symmetry and inflorescence architecture. In the Helianthus annuus genome, ten CYC/TB1 genes have been identified. Studies performed on mutants recognised HaCYC2c as one of the key players controlling zygomorphism in sunflower. We identified CYC2c genes in the diploid Helianthus decapetalus (HdCYC2c) and in the interspecific hybrid Helianthus × multiflorus (H × mCYC2cA and H × mCYC2cB), a triploid (2n = 3× = 51), originated from unreduced eggs of H. decapetalus fertilised by reduced H. annuus male gametes. Phylogenetic analysis showed that HdCYC2c and H × mCYC2c were placed within a CYC2 subclade together with HaCYC2c but distinct from it. The present data showed that in H. × multiflorus the allele derived from H. annuus is deleted or highly modified. The H. × multiflorus taxon exists as radiate and ligulate inflorescence types. We analysed CYC2c expression in H. decapetalus and in the cultivar 'Soleil d'Or' of H. × multiflorus, a ligulate inflorescence type with actinomorphic corolla of disk flowers transformed into a zygomorphic ray-like corolla. In H. decapetalus, the HdCYC2c gene showed differential expression between developing flower types, being up-regulated in the corolla of ray flowers in comparison to the disk flower corolla. In H. × multiflorus, an insertion of 865 bp, which is part of a CACTA transposable element, was found in the 5'-untranslated region (5'-UTR) of H × mCYC2cB. This insertion could promote, even with epigenetic mechanisms, ectopic expression of the gene throughout the inflorescence, resulting in the observed loss of actinomorphy and originating a ligulate head.
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Affiliation(s)
- M Fambrini
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - M Bellanca
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - M Costa Muñoz
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
- Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - G Usai
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - A Cavallini
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
| | - C Pugliesi
- Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy
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17
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Abstract
Contents Summary 70 I. Introduction 70 II. What is the floral ground plan? 71 III. Diversity and evolution of the floral ground plan 72 IV. Genetic mechanisms 77 V. What's next? 82 Acknowledgements 83 References 83 SUMMARY: The floral ground plan is a map of where and when floral organ primordia arise. New results combining the defined phylogeny of flowering plants with extensive character mapping have predicted that the angiosperm ancestor had whorls rather than spirals of floral organs in large numbers, and was bisexual. More confidently, the monocot ancestor likely had three organs in each whorl, whereas the rosid and asterid ancestor (Pentapetalae) had five, with the perianth now divided into sepals and petals. Genetic mechanisms underlying the establishment of the floral ground plan are being deduced using model species, the rosid Arabidopsis, the asterid Antirrhinum, and in grasses such as rice. In this review, evolutionary and genetic conclusions are drawn together, especially considering how known genes may control individual processes in the development and evolution of ground plans. These components include organ phyllotaxis, boundary formation, organ identity, merism (the number or organs per whorl), variation in the form of primordia, organ fusion, intercalary growth, floral symmetry, determinacy and, finally, cases where the distinction between flowers and inflorescences is blurred. It seems likely that new pathways of ground plan evolution, and new signalling mechanisms, will soon be uncovered by integrating morphological and genetic approaches.
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Affiliation(s)
- David R Smyth
- School of Biological Sciences, Monash University, Clayton Campus, Melbourne, Victoria, 3800, Australia
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18
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Bukhari G, Zhang J, Stevens PF, Zhang W. Evolution of the process underlying floral zygomorphy development in pentapetalous angiosperms. Am J Bot 2017; 104:1846-1856. [PMID: 29247025 DOI: 10.3732/ajb.1700229] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 10/17/2017] [Indexed: 06/07/2023]
Abstract
PREMISE OF THE STUDY Observations of floral ontogeny indicated that floral organ initiation in pentapetalous flowers most commonly results in a median-abaxial (MAB) petal during early development, a median-adaxial (MAD) petal being less common. Such different patterns of floral organ initiation might be linked with different morphologies of floral zygomorphy that have evolved in Asteridae. Here, we provide the first study of zygomorphy in pentapetalous angiosperms placed in a phylogenetic framework, the goal being to find if the different patterns of floral organ initiation are connected with particular patterns of zygomorphy. METHODS We analyzed patterns of floral organ initiation and displays of zygomorphy, extracted from floral diagrams representing 405 taxa in 330 genera, covering 83% of orders (30 out of 36) and 37% of families (116 out of 313) in core eudicots in the context of a phylogeny using ancestral state reconstructions. KEY RESULTS The MAB petal initiation is the ancestral state of the pattern of floral organ initiation in pentapetalous angiosperms. Taxa with MAD petal initiation represent ∼30 independent origins from the ancestral MAB initiation. There are distinct developmental processes that give rise to zygomorphy in different lineages of pentapetalous angiosperms, closely related lineages being likely to share similar developmental processes. CONCLUSIONS We have demonstrated that development indeed constrains the processes that give rise to floral zygomorphy, while phylogenetic distance allows relaxation of these constraints, which provides novel insights on the role that development plays in the evolution of floral zygomorphy.
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Affiliation(s)
- Ghadeer Bukhari
- Department of Biology, Virginia Commonwealth University, 1000 West Cary Street, Richmond, Virginia 23284 USA
| | - Jingbo Zhang
- Department of Biology, Virginia Commonwealth University, 1000 West Cary Street, Richmond, Virginia 23284 USA
| | - Peter F Stevens
- Department of Biology, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121 USA
| | - Wenheng Zhang
- Department of Biology, Virginia Commonwealth University, 1000 West Cary Street, Richmond, Virginia 23284 USA
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19
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Damerval C, Becker A. Genetics of flower development in Ranunculales - a new, basal eudicot model order for studying flower evolution. New Phytol 2017; 216:361-366. [PMID: 28052360 DOI: 10.1111/nph.14401] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 11/20/2016] [Indexed: 05/20/2023]
Abstract
Contents 361 I. 361 II. 362 III. 363 IV. 364 V. 364 Acknowledgements 365 References 365 SUMMARY: Ranunculales, the sister group to all other eudicots, encompasses species with a remarkable floral diversity, which are currently emerging as new model organisms to address questions relating to the genetic architecture of flower morphology and its evolution. These questions concern either traits only found in members of the Ranunculales or traits that have convergently evolved in other large clades of flowering plants. We present recent results obtained on floral organ identity and number, symmetry evolution and spur formation in Ranunculales species. We discuss benefits and future prospects of evo-devo studies in Ranunculales, which can provide the opportunity to decipher the genetic architecture of novel floral traits and also to appraise the degree of conservation of genetic mechanisms involved in homoplasious traits.
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Affiliation(s)
- Catherine Damerval
- GQE - Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Gif-sur-Yvette, 91190, France
| | - Annette Becker
- Justus-Liebig-Universität Gießen, Institut für Botanik, Heinrich-Buff-Ring 38, Gießen, 35392, Germany
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20
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Berger BA, Han J, Sessa EB, Gardner AG, Shepherd KA, Ricigliano VA, Jabaily RS, Howarth DG. The unexpected depths of genome-skimming data: A case study examining Goodeniaceae floral symmetry genes. Appl Plant Sci 2017; 5:apps.1700042. [PMID: 29109919 PMCID: PMC5664964 DOI: 10.3732/apps.1700042] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 09/07/2017] [Indexed: 05/20/2023]
Abstract
PREMISE OF THE STUDY The use of genome skimming allows systematists to quickly generate large data sets, particularly of sequences in high abundance (e.g., plastomes); however, researchers may be overlooking data in low abundance that could be used for phylogenetic or evo-devo studies. Here, we present a bioinformatics approach that explores the low-abundance portion of genome-skimming next-generation sequencing libraries in the fan-flowered Goodeniaceae. METHODS Twenty-four previously constructed Goodeniaceae genome-skimming Illumina libraries were examined for their utility in mining low-copy nuclear genes involved in floral symmetry, specifically the CYCLOIDEA (CYC)-like genes. De novo assemblies were generated using multiple assemblers, and BLAST searches were performed for CYC1, CYC2, and CYC3 genes. RESULTS Overall Trinity, SOAPdenovo-Trans, and SOAPdenovo implementing lower k-mer values uncovered the most data, although no assembler consistently outperformed the others. Using SOAPdenovo-Trans across all 24 data sets, we recovered four CYC-like gene groups (CYC1, CYC2, CYC3A, and CYC3B) from a majority of the species. Alignments of the fragments included the entire coding sequence as well as upstream and downstream regions. DISCUSSION Genome-skimming data sets can provide a significant source of low-copy nuclear gene sequence data that may be used for multiple downstream applications.
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Affiliation(s)
- Brent A. Berger
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, New York 11439 USA
| | - Jiahong Han
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, New York 11439 USA
| | - Emily B. Sessa
- Department of Biology, University of Florida, Box 118525, Gainesville, Florida 32611 USA
| | - Andrew G. Gardner
- Department of Biological Sciences, California State University, Stanislaus, One University Circle, Turlock, California 95382 USA
| | - Kelly A. Shepherd
- Western Australian Herbarium, Department of Biodiversity, Conservation and Attractions, 17 Dick Perry Avenue, Kensington 6151, Western Australia, Australia
| | - Vincent A. Ricigliano
- USDA-ARS Carl Hayden Bee Research Center, 2000 E. Allen Road, Tucson, Arizona 85719 USA
| | - Rachel S. Jabaily
- Department of Biology, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112 USA
| | - Dianella G. Howarth
- Department of Biological Sciences, St. John’s University, 8000 Utopia Parkway, Queens, New York 11439 USA
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21
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Berger BA, Han J, Sessa EB, Gardner AG, Shepherd KA, Ricigliano VA, Jabaily RS, Howarth DG. The unexpected depths of genome-skimming data: A case study examining Goodeniaceae floral symmetry genes. Appl Plant Sci 2017. [PMID: 29109919 DOI: 10.5061/dryad.0500c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
PREMISE OF THE STUDY The use of genome skimming allows systematists to quickly generate large data sets, particularly of sequences in high abundance (e.g., plastomes); however, researchers may be overlooking data in low abundance that could be used for phylogenetic or evo-devo studies. Here, we present a bioinformatics approach that explores the low-abundance portion of genome-skimming next-generation sequencing libraries in the fan-flowered Goodeniaceae. METHODS Twenty-four previously constructed Goodeniaceae genome-skimming Illumina libraries were examined for their utility in mining low-copy nuclear genes involved in floral symmetry, specifically the CYCLOIDEA (CYC)-like genes. De novo assemblies were generated using multiple assemblers, and BLAST searches were performed for CYC1, CYC2, and CYC3 genes. RESULTS Overall Trinity, SOAPdenovo-Trans, and SOAPdenovo implementing lower k-mer values uncovered the most data, although no assembler consistently outperformed the others. Using SOAPdenovo-Trans across all 24 data sets, we recovered four CYC-like gene groups (CYC1, CYC2, CYC3A, and CYC3B) from a majority of the species. Alignments of the fragments included the entire coding sequence as well as upstream and downstream regions. DISCUSSION Genome-skimming data sets can provide a significant source of low-copy nuclear gene sequence data that may be used for multiple downstream applications.
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Affiliation(s)
- Brent A Berger
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, New York 11439 USA
| | - Jiahong Han
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, New York 11439 USA
| | - Emily B Sessa
- Department of Biology, University of Florida, Box 118525, Gainesville, Florida 32611 USA
| | - Andrew G Gardner
- Department of Biological Sciences, California State University, Stanislaus, One University Circle, Turlock, California 95382 USA
| | - Kelly A Shepherd
- Western Australian Herbarium, Department of Biodiversity, Conservation and Attractions, 17 Dick Perry Avenue, Kensington 6151, Western Australia, Australia
| | - Vincent A Ricigliano
- USDA-ARS Carl Hayden Bee Research Center, 2000 E. Allen Road, Tucson, Arizona 85719 USA
| | - Rachel S Jabaily
- Department of Biology, Rhodes College, 2000 N. Parkway, Memphis, Tennessee 38112 USA
| | - Dianella G Howarth
- Department of Biological Sciences, St. John's University, 8000 Utopia Parkway, Queens, New York 11439 USA
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22
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Zimmerman E, Herendeen PS, Lewis GP, Bruneau A. Floral evolution and phylogeny of the Dialioideae, a diverse subfamily of tropical legumes. Am J Bot 2017; 104:1019-1041. [PMID: 28710127 DOI: 10.3732/ajb.1600436] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 05/12/2017] [Indexed: 05/11/2023]
Abstract
PREMISE OF THE STUDY The Dialioideae is an early diverging clade of caesalpinioid legumes containing approximately 85 species in 17 genera. Dialioideae floral morphology is highly variable and may provide clues to caesalpinioid evolution, but a well-resolved phylogeny is needed. Here, we have carried out a comprehensive morphological study of 78 Dialioideae and four outgroup species. METHODS For all available Dialioideae DNA samples, the plastid rpS16 and trnL introns were sequenced. A combined phylogenetic analysis using the parsimony criterion was completed on a reduced taxon set for which both molecular and morphological data were available. Highly supported clades from the strict consensus tree of this analysis were then used to constrain the nodes of a second analysis on an expanded taxon set with missing molecular data for some taxa. KEY RESULTS Several new, highly supported relationships have been discovered at the species and genus levels. The loss of the antepetalous stamen whorl was found to be a synapomorphy for most of the clade. CONCLUSIONS A high degree of organ loss is common in the Dialioideae and often results in a bilaterally symmetrical flower. The absence of consistent morphological features in the Dialioideae, coupled with the small size of each florally diagnosed genus, suggests a lack of canalization in the floral evolution in early diverging legume lineages.
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Affiliation(s)
- Erin Zimmerman
- Institut de Recherche en Biologie Végétale and Département de Sciences Biologiques, Université de Montréal, 4101 rue Sherbrooke Est, Montréal, Québec, H1X 2B2, Canada
| | | | - Gwilym P Lewis
- Comparative Plant and Fungal Biology Department, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE, United Kingdom
| | - Anne Bruneau
- Institut de Recherche en Biologie Végétale and Département de Sciences Biologiques, Université de Montréal, 4101 rue Sherbrooke Est, Montréal, Québec, H1X 2B2, Canada
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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. Ann Bot 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Madrigal Y, Alzate JF, Pabón-Mora N. Evolution and Expression Patterns of TCP Genes in Asparagales. Front Plant Sci 2017; 8:9. [PMID: 28144250 PMCID: PMC5239819 DOI: 10.3389/fpls.2017.00009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 01/03/2017] [Indexed: 05/09/2023]
Abstract
CYCLOIDEA-like genes are involved in the symmetry gene network, limiting cell proliferation in the dorsal regions of bilateral flowers in core eudicots. CYC-like and closely related TCP genes (acronym for TEOSINTE BRANCHED1, CYCLOIDEA, and PROLIFERATION CELL FACTOR) have been poorly studied in Asparagales, the largest order of monocots that includes both bilateral flowers in Orchidaceae (ca. 25.000 spp) and radially symmetrical flowers in Hypoxidaceae (ca. 200 spp). With the aim of assessing TCP gene evolution in the Asparagales, we isolated TCP-like genes from publicly available databases and our own transcriptomes of Cattleya trianae (Orchidaceae) and Hypoxis decumbens (Hypoxidaceae). Our matrix contains 452 sequences representing the three major clades of TCP genes. Besides the previously identified CYC specific core eudicot duplications, our ML phylogenetic analyses recovered an early CIN-like duplication predating all angiosperms, two CIN-like Asparagales-specific duplications and a duplication prior to the diversification of Orchidoideae and Epidendroideae. In addition, we provide evidence of at least three duplications of PCF-like genes in Asparagales. While CIN-like and PCF-like genes have multiplied in Asparagales, likely enhancing the genetic network for cell proliferation, CYC-like genes remain as single, shorter copies with low expression. Homogeneous expression of CYC-like genes in the labellum as well as the lateral petals suggests little contribution to the bilateral perianth in C. trianae. CIN-like and PCF-like gene expression suggests conserved roles in cell proliferation in leaves, sepals and petals, carpels, ovules and fruits in Asparagales by comparison with previously reported functions in core eudicots and monocots. This is the first large scale analysis of TCP-like genes in Asparagales that will serve as a platform for in-depth functional studies in emerging model monocots.
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Affiliation(s)
- Yesenia Madrigal
- Facultad de Ciencias Exactas y Naturales, Instituto de Biología, Universidad de AntioquiaMedellín, Colombia
| | - Juan F. Alzate
- Centro Nacional de Secuenciación Genómica, Sede de Investigación Universitaria, Facultad de Medicina, Universidad de AntioquiaMedellín, Colombia
| | - Natalia Pabón-Mora
- Facultad de Ciencias Exactas y Naturales, Instituto de Biología, Universidad de AntioquiaMedellín, Colombia
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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. Front Plant Sci 2017; 8:589. [PMID: 28487706 PMCID: PMC5403951 DOI: 10.3389/fpls.2017.00589] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Diller C, Fenster CB. Corolla chirality does not contribute to directed pollen movement in Hypericum perforatum (Hypericaceae): mirror image pinwheel flowers function as radially symmetric flowers in pollination. Ecol Evol 2016; 6:5076-86. [PMID: 27547334 PMCID: PMC4979728 DOI: 10.1002/ece3.2268] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 05/24/2016] [Accepted: 05/25/2016] [Indexed: 12/19/2022] Open
Abstract
Corolla chirality, the pinwheel arrangement of petals within a flower, is found throughout the core eudicots. In 15 families, different chiral type flowers (i.e., right or left rotated corolla) exist on the same plant, and this condition is referred to as unfixed/enantiomorphic corolla chirality. There are no investigations on the significance of unfixed floral chirality on directed pollen movement even though analogous mirror image floral designs, for example, enantiostyly, has evolved in response to selection to direct pollinator and pollen movement. Here, we examine the role of corolla chirality on directing pollen transfer, pollinator behavior, and its potential influence on disassortative mating. We quantified pollen transfer and pollinator behavior and movement for both right and left rotated flowers in two populations of Hypericum perforatum. In addition, we quantified the number of right and left rotated flowers at the individual level. Pollinators were indifferent to corolla chirality resulting in no difference in pollen deposition between right and left flowers. Corolla chirality had no effect on pollinator and pollen movement between and within chiral morphs. Unlike other mirror image floral designs, corolla chirality appears to play no role in promoting disassortative mating in this species.
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Affiliation(s)
- Carolina Diller
- Department of Biology University of Maryland College Park Maryland 20742
| | - Charles B Fenster
- Department of Biology and Microbiology South Dakota State University Brookings South Dakota 57007
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Reyes E, Morlon H, Sauquet H. Presence in Mediterranean hotspots and floral symmetry affect speciation and extinction rates in Proteaceae. New Phytol 2015; 207:401-410. [PMID: 25537140 DOI: 10.1111/nph.13244] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 11/24/2014] [Indexed: 06/04/2023]
Abstract
The Proteaceae is a large angiosperm family displaying the common pattern of uneven distribution of species among genera. Previous studies have shown that this disparity is a result of variation in diversification rates across lineages, but the reasons for this variation are still unclear. Here, we tested the impact of floral symmetry and occurrence in Mediterranean climate regions on speciation and extinction rates in the Proteaceae. A rate shift analysis was conducted on dated genus-level phylogenetic trees of the Proteaceae. Character-dependent analyses were used to test for differences in diversification rates between actinomorphic and zygomorphic lineages and between lineages located within or outside Mediterranean climate regions. The rate shift analysis identified 5-10 major diversification rate shifts in the Proteaceae tree. The character-dependent analyses showed that speciation rates, extinction rates and net diversification rates of the Proteaceae were significantly higher for lineages occurring in Mediterranean hotspots. Higher speciation and extinction rates were also detected for zygomorphic species, but net diversification rates appeared to be similar in actinomorphic and zygomorphic Proteaceae. Presence in Mediterranean hotspots favors Proteaceae diversification. In contrast with observations at the scale of angiosperms, floral symmetry is not a trait that strongly influences their evolutionary success.
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Affiliation(s)
- Elisabeth Reyes
- Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, Université Paris-Sud, 91405, Orsay, France
- CMAP, École Polytechnique, CNRS UMR 7641, Route de Saclay, 91128, Palaiseau, France
| | - Hélène Morlon
- CMAP, École Polytechnique, CNRS UMR 7641, Route de Saclay, 91128, Palaiseau, France
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS UMR 8197, 46 rue d'Ulm, 75005, Paris, France
| | - Hervé Sauquet
- Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, Université Paris-Sud, 91405, Orsay, France
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Sauquet H, Carrive L, Poullain N, Sannier J, Damerval C, Nadot S. Zygomorphy evolved from disymmetry in Fumarioideae (Papaveraceae, Ranunculales): new evidence from an expanded molecular phylogenetic framework. Ann Bot 2015; 115:895-914. [PMID: 25814061 PMCID: PMC4407061 DOI: 10.1093/aob/mcv020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 12/23/2014] [Accepted: 01/22/2015] [Indexed: 05/11/2023]
Abstract
BACKGROUND AND AIMS Fumarioideae (20 genera, 593 species) is a clade of Papaveraceae (Ranunculales) characterized by flowers that are either disymmetric (i.e. two perpendicular planes of bilateral symmetry) or zygomorphic (i.e. one plane of bilateral symmetry). In contrast, the other subfamily of Papaveraceae, Papaveroideae (23 genera, 230 species), has actinomorphic flowers (i.e. more than two planes of symmetry). Understanding of the evolution of floral symmetry in this clade has so far been limited by the lack of a reliable phylogenetic framework. Pteridophyllum (one species) shares similarities with Fumarioideae but has actinomorphic flowers, and the relationships among Pteridophyllum, Papaveroideae and Fumarioideae have remained unclear. This study reassesses the evolution of floral symmetry in Papaveraceae based on new molecular phylogenetic analyses of the family. METHODS Maximum likelihood, Bayesian and maximum parsimony phylogenetic analyses of Papaveraceae were conducted using six plastid markers and one nuclear marker, sampling Pteridophyllum, 18 (90 %) genera and 73 species of Fumarioideae, 11 (48 %) genera and 11 species of Papaveroideae, and a wide selection of outgroup taxa. Floral characters recorded from the literature were then optimized onto phylogenetic trees to reconstruct ancestral states using parsimony, maximum likelihood and reversible-jump Bayesian approaches. KEY RESULTS Pteridophyllum is not nested in Fumarioideae. Fumarioideae are monophyletic and Hypecoum (18 species) is the sister group of the remaining genera. Relationships within the core Fumarioideae are well resolved and supported. Dactylicapnos and all zygomorphic genera form a well-supported clade nested among disymmetric taxa. CONCLUSIONS Disymmetry of the corolla is a synapomorphy of Fumarioideae and is strongly correlated with changes in the androecium and differentiation of middle and inner tepal shape (basal spurs on middle tepals). Zygomorphy subsequently evolved from disymmetry either once (with a reversal in Dactylicapnos) or twice (Capnoides, other zygomorphic Fumarioideae) and appears to be correlated with the loss of one nectar spur.
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Affiliation(s)
- Hervé Sauquet
- Université Paris-Sud, Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, 91405 Orsay, France and CNRS, UMR 0320/UMR 8120 Génétique Quantitative et Evolution - Le Moulon, INRA/Université Paris-Sud/CNRS/AgroParisTech, Ferme du Moulon, 91190 Gif-sur-Yvette, France
| | - Laetitia Carrive
- Université Paris-Sud, Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, 91405 Orsay, France and CNRS, UMR 0320/UMR 8120 Génétique Quantitative et Evolution - Le Moulon, INRA/Université Paris-Sud/CNRS/AgroParisTech, Ferme du Moulon, 91190 Gif-sur-Yvette, France
| | - Noëlie Poullain
- Université Paris-Sud, Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, 91405 Orsay, France and CNRS, UMR 0320/UMR 8120 Génétique Quantitative et Evolution - Le Moulon, INRA/Université Paris-Sud/CNRS/AgroParisTech, Ferme du Moulon, 91190 Gif-sur-Yvette, France
| | - Julie Sannier
- Université Paris-Sud, Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, 91405 Orsay, France and CNRS, UMR 0320/UMR 8120 Génétique Quantitative et Evolution - Le Moulon, INRA/Université Paris-Sud/CNRS/AgroParisTech, Ferme du Moulon, 91190 Gif-sur-Yvette, France
| | - Catherine Damerval
- Université Paris-Sud, Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, 91405 Orsay, France and CNRS, UMR 0320/UMR 8120 Génétique Quantitative et Evolution - Le Moulon, INRA/Université Paris-Sud/CNRS/AgroParisTech, Ferme du Moulon, 91190 Gif-sur-Yvette, France
| | - Sophie Nadot
- Université Paris-Sud, Laboratoire Écologie, Systématique, Évolution, CNRS UMR 8079, 91405 Orsay, France and CNRS, UMR 0320/UMR 8120 Génétique Quantitative et Evolution - Le Moulon, INRA/Université Paris-Sud/CNRS/AgroParisTech, Ferme du Moulon, 91190 Gif-sur-Yvette, France
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Lázaro A, Totland O. The influence of floral symmetry, dependence on pollinators and pollination generalization on flower size variation. Ann Bot 2014; 114:157-65. [PMID: 24838838 PMCID: PMC4071101 DOI: 10.1093/aob/mcu083] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 04/02/2014] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS The pollinator-mediated stabilizing selection hypothesis suggests that the specialized pollination system of zygomorphic flowers might cause stabilizing selection, reducing their flower size variation compared with actinomorphic flowers. However, the degree of ecological generalization and of dependence on pollinators varies greatly among species of both flower symmetry types and this may also affect flower size variation. METHODS Data on 43 species from two contrasting communities (one alpine and one lowland community) were used to test the relationships and interactions between flower size phenotypic variation, floral symmetry, ecological pollination generalization and species' dependence on pollinators. KEY RESULTS Contrary to what was expected, higher flower size variation was found in zygomorphic than in actinomorphic species in the lowland community, and no difference in flower size variation was found between symmetry types in the alpine community. The relationship between floral symmetry and flower size variation depended on ecological generalization and species' dependence on pollinators, although the influence of ecological generalization was only detected in the alpine community. Zygomorphic species that were highly dependent on pollinators and that were ecologically specialized were less variable in flower size than ecologically generalist and selfing zygomorphic species, supporting the pollinator-mediated stabilizing selection hypothesis. However, these relationships were not found in actinomorphic species, probably because they are not dependent on any particular pollinator for efficient pollination and therefore their flower size always shows moderate levels of variation. CONCLUSIONS The study suggests that the relationship between flower size variation and floral symmetry may be influenced by population-dependent factors, such as ecological generalization and species' dependence on pollinators.
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Affiliation(s)
- A Lázaro
- Mediterranean Institute for Advanced Studies, C/ Miquel Marqués 21, 07190, Esporles, Balearic Islands, Spain
| | - O Totland
- Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, PO Box 5003 Ås, Norway
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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. New Phytol 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Zhang W, Steinmann VW, Nikolov L, Kramer EM, Davis CC. Divergent genetic mechanisms underlie reversals to radial floral symmetry from diverse zygomorphic flowered ancestors. Front Plant Sci 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Jabbour F, Damerval C, Nadot S. Evolutionary trends in the flowers of Asteridae: is polyandry an alternative to zygomorphy? Ann Bot 2008; 102:153-65. [PMID: 18511411 PMCID: PMC2712368 DOI: 10.1093/aob/mcn082] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2008] [Revised: 03/17/2008] [Accepted: 04/21/2008] [Indexed: 05/12/2023]
Abstract
BACKGROUND AND AIMS Floral symmetry presents two main states in angiosperms, actinomorphy (polysymmetry or radial symmetry) and zygomorphy (monosymmetry or bilateral symmetry). Transitions from actinomorphy to zygomorphy have occurred repeatedly among flowering plants, possibly in coadaptation with specialized pollinators. In this paper, the rules controlling the evolution of floral symmetry were investigated to determine in which architectural context zygomorphy can evolve. METHODS Floral traits potentially associated with perianth symmetry shifts in Asteridae, one of the major clades of the core eudicots, were selected: namely the perianth merism, the presence and number of spurs, and the androecium organ number. The evolution of these characters was optimized on a composite tree. Correlations between symmetry and the other morphological traits were then examined using a phylogenetic comparative method. KEY RESULTS The analyses reveal that the evolution of floral symmetry in Asteridae is conditioned by both androecium organ number and perianth merism and that zygomorphy is a prerequisite to the emergence of spurs. CONCLUSIONS The statistically significant correlation between perianth zygomorphy and oligandry suggests that the evolution of floral symmetry could be canalized by developmental or spatial constraint. Interestingly, the evolution of polyandry in an actinomorphic context appears as an alternative evolutionary pathway to zygomorphy in Asteridae. These results may be interpreted either in terms of plant-pollinator adaptation or in terms of developmental or physical constraints. The results are discussed in relation to current knowledge about the molecular bases underlying floral symmetry.
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Affiliation(s)
- Florian Jabbour
- Université Paris-Sud, Laboratoire Ecologie, Systématique, Evolution, CNRS UMR 8079, AgroParisTech, Orsay, F-91405, France.
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Bello MA, Hawkins JA, Rudall PJ. Floral morphology and development in Quillajaceae and Surianaceae (Fabales), the species-poor relatives of Leguminosae and Polygalaceae. Ann Bot 2007; 100:1491-505. [PMID: 17906327 PMCID: PMC2759219 DOI: 10.1093/aob/mcm228] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Revised: 06/27/2007] [Accepted: 07/30/2007] [Indexed: 05/17/2023]
Abstract
BACKGROUND AND AIMS Molecular phylogenies have suggested a new circumscription for Fabales to include Leguminosae, Quillajaceae, Surianaceae and Polygalaceae. However, recent attempts to reconstruct the interfamilial relationships of the order have resulted in several alternative hypotheses, including a sister relationship between Quillajaceae and Surianaceae, the two species-poor families of Fabales. Here, floral morphology and ontogeny of these two families are investigated to explore evidence of a potential relationship between them. Floral traits are discussed with respect to early radiation in the order. METHODS Floral buds of representatives of Quillajaceae and Surianaceae were dissected and observed using light microscopy and scanning electron microscopy. KEY RESULTS Quillajaceae and Surianaceae possess some common traits, such as inflorescence morphology and perianth initiation, but development and organization of their reproductive whorls differ. In Quillaja, initiation of the diplostemonous androecium is unidirectional, overlapping with the petal primordia. In contrast, Suriana is obdiplostemonous, and floral organ initiation is simultaneous. Independent initiation of five carpels is common to both Quillaja and Suriana, but subsequent development differs; the antesepalous carpels of Quillaja become fused proximally and exhibit two rows of ovules, and in Suriana the gynoecium is apocarpous, gynobasic, with antepetalous biovulate carpels. CONCLUSIONS Differences in the reproductive development and organization of Quillajaceae and Surianaceae cast doubt on their potential sister relationship. Instead, Quillaja resembles Leguminosae in some floral traits, a hypothesis not suggested by molecular-based phylogenies. Despite implicit associations of zygomorphy with species-rich clades and actinomorphy with species-poor families in Fabales, this correlation sometimes fails due to high variation in floral symmetry. Studies considering specific derived clades and reproductive biology could address more precise hypotheses of key innovation and differential diversification in the order.
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Affiliation(s)
- M. A. Bello
- School of Biological Sciences, Plant Sciences Laboratories, The University of Reading, Reading, Berkshire RG1 6AS, UK
- Jodrell Laboratory, Royal Botanic Gardens Kew, Richmond, Surrey TW9 3DS, UK
| | - J. A. Hawkins
- School of Biological Sciences, Plant Sciences Laboratories, The University of Reading, Reading, Berkshire RG1 6AS, UK
| | - P. J. Rudall
- Jodrell Laboratory, Royal Botanic Gardens Kew, Richmond, Surrey TW9 3DS, UK
- For correspondence. E-mail
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Damerval C, Nadot S. Evolution of perianth and stamen characteristics with respect to floral symmetry in Ranunculales. Ann Bot 2007; 100:631-40. [PMID: 17428835 PMCID: PMC2533616 DOI: 10.1093/aob/mcm041] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Revised: 01/10/2007] [Accepted: 01/30/2007] [Indexed: 05/04/2023]
Abstract
BACKGROUND AND AIMS Floral symmetry presents two main states in angiosperms, namely polysymmetry and monosymmetry. Monosymmetry is thought to have evolved several times independently from polysymmetry, possibly in co-adaptation with specialized pollinators. Monosymmetry commonly refers to the perianth, even though associated androecium modifications have been reported. The evolution of perianth symmetry is examined with respect to traits of flower architecture in the Ranunculales, the sister group to all other eudicots, which present a large diversity of floral forms. METHODS Characters considered were perianth merism, calyx, corolla and androecium symmetry, number of stamens and spurs. Character evolution was optimized on a composite phylogenetic tree of Ranunculales using maximum parsimony. KEY RESULTS The ancestral state for merism could not be inferred because the basalmost Eupteleaceae lack a perianth and have a variable number of stamens. The Papaveraceae are dimerous, and the five other families share a common trimerous ancestor. Shifts from trimery to dimery (or reverse) are observed. Pentamery evolved in Ranunculaceae. Ranunculales except Eupteleaceae, present a polysymmetric ancestral state. Monosymmetry evolved once within Papaveraceae, Ranunculaceae and Menispermaceae (female flowers only). Oligandry is the ancestral state for all Ranunculales, and polyandry evolved several times independently, in Papaveraceae, Menispermaceae, Berberidaceae and Ranunculaceae, with two reversions to oligandry in the latter. The ancestral state for androecium symmetry is ambiguous for the Ranunculales, while polysymmetry evolved immediately after the divergence of Eupteleaceae. A disymmetric androecium evolved in Papaveraceae. The ancestral state for spurs is none. Multiple spurs evolved in Papaveraceae, Berberidaceae and Ranunculaceae, and single spurs occur in Papaveraceae and Ranunculaceae. CONCLUSIONS The evolution of symmetry appears disconnected from changes in merism and stamen number, although monosymmetry never evolved in the context of an open ground plan. In bisexual species, monosymmetry evolved coincidently with single spurs, allowing us to propose an evolutionary scenario for Papaveraceae.
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Affiliation(s)
- Catherine Damerval
- CNRS UMR Génétique Végétale, INRA, AgroParisTech, Université Paris-Sud, Gif-sur-Yvette, F-91190, France.
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Abstract
BACKGROUND AND AIMS Based on molecular phylogenetic studies, the unigeneric family Eupteleaceae has a prominent phylogenetic position at or near the base of Ranunculales, which, in turn, appear at the base of eudicots. The aim of the present paper is to reveal developmental features of the flowers and to put the genus in a morphological context with other basal eudicots. METHODS Flowers in all developmental stages of Euptelea pleiosperma were collected in the wild at intervals of 7-10 d in the critical stages and studied with a scanning electron microscope. KEY RESULTS Remnants of a perianth are lacking throughout flower development. Floral symmetry changes from monosymmetric to asymmetric to disymmetric during development. Asymmetry is expressed in that the sequence of stamen initiation is from the centre to both lateral sides on the adaxial side of the flower but starting from one lateral side and proceeding to the other on the abaxial side. Despite the pronounced floral disymmetry, a dimerous pattern of floral organs was not found. The carpel primordia arise between the already large stamens and alternate with them. Stamens and carpels each form a somewhat irregular whorl. The carpels are ascidiate from the beginning. The stigma differentiates as two crests along the ventral slit of the ovary. The few lateral ovules alternate with each other. CONCLUSIONS Although the flowers have some unusual autapomorphies (wind pollination, lack of a perianth, pronounced disymmetry of the floral base, long connective protrusion, long temporal gap between androecium and gynoecium initiation, small space for carpel initiation), they show some plesiomorphies at the level of basal eudicots (free carpels, basifixed anthers, whorled phyllotaxis), and thus fit well in Ranunculales.
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Affiliation(s)
- Yi Ren
- College of Life Sciences, Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education, Shaanxi Normal University, Xi'an, 710062 China.
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