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Liu X, Wang Q, Jiang G, Wan Q, Dong B, Lu M, Deng J, Zhong S, Wang Y, Khan IA, Xiao Z, Fang Q, Zhao H. Temperature-responsive module of OfAP1 and OfLFY regulates floral transition and floral organ identity in Osmanthus fragrans. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 203:108076. [PMID: 37832366 DOI: 10.1016/j.plaphy.2023.108076] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 09/14/2023] [Accepted: 09/30/2023] [Indexed: 10/15/2023]
Abstract
The MADS-box transcription factor APETELA1 (AP1) is crucially important for reproductive developmental processes. The function of AP1 and the classic LFY-AP1 interaction in woody plants are not widely known. Here, the OfAP1-a gene from the continuously flowering plant Osmanthus fragrans 'Sijigui' was characterized, and its roles in regulating flowering time, petal number robustness and floral organ identity were determined using overexpression in Arabidopsis thaliana and Nicotiana tabacum. The expression of OfAP1-a was significantly induced by low ambient temperature and was upregulated with the floral transition process. Ectopic expression OfAP1-a revealed its classic function in flowering and flower ABC models. The expression of OfAP1-a is inhibited by LEAFY (OfLFY) through direct promoter binding, as confirmed by yeast one-hybrid and dual luciferase assays. Arabidopsis plants overexpressing OfAP1-a exhibited accelerated flowering and altered floral organ identities. Moreover, OfAP1-a-overexpressing plants displayed variable petal numbers. Likewise, the overexpression of OfLFY in Arabidopsis and Nicotiana altered petal number robustness and inflorescence architecture, partially by regulating native AP1 in transformed plants. Furthermore, we performed RNA-seq analysis of transgenic Nicotiana plants. DEGs were identified by transcriptome analysis, and we found that the expression of several floral homeotic genes was altered in both OfAP1-a and OfLFY-overexpressing transgenic lines. Our results suggest that OfAP1-a may play important roles during floral transition and development in response to ambient temperature. OfAP1-a functions as a petal number modulator and may directly activate a subset of flowers to regulate floral organ formation. OfAP1-a and OfLFY mutually regulate the expression of each other and coregulate genes that might be involved in these phenotypes related to flowering. The results provide valuable data for understanding the function of the LFY-AP1 module in the reproductive process and shaping floral structures in woody plants.
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Affiliation(s)
- Xiaohan Liu
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Qianqian Wang
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Gege Jiang
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Qianqian Wan
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Bin Dong
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Mei Lu
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Jinping Deng
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Shiwei Zhong
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Yiguang Wang
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Irshad Ahmad Khan
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Zheng Xiao
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China
| | - Qiu Fang
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China.
| | - Hongbo Zhao
- Zhejiang Provincial Key Laboratory of Germplasm Innovation and Utilization for Garden Plants, School of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China; Key Laboratory of National Forestry and Grassland Administration on Germplasm Innovation and Utilization for Southern Garden Plants, Hangzhou, 311300, China.
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Lembinen S, Cieslak M, Zhang T, Mackenzie K, Elomaa P, Prusinkiewicz P, Hytönen T. Diversity of woodland strawberry inflorescences arises from heterochrony regulated by TERMINAL FLOWER 1 and FLOWERING LOCUS T. THE PLANT CELL 2023; 35:2079-2094. [PMID: 36943776 DOI: 10.1093/plcell/koad086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 02/21/2023] [Accepted: 02/26/2023] [Indexed: 05/30/2023]
Abstract
A vast variety of inflorescence architectures have evolved in angiosperms. Here, we analyze the diversity and development of the woodland strawberry (Fragaria vesca) inflorescence. Contrary to historical classifications, we show that it is a closed thyrse: a compound inflorescence with determinate primary monopodial axis and lateral sympodial branches, thus combining features of racemes and cymes. We demonstrate that this architecture is generated by 2 types of inflorescence meristems differing in their geometry. We further show that woodland strawberry homologs of TERMINAL FLOWER 1 (FvTFL1) and FLOWERING LOCUS T (FvFT1) regulate the development of both the racemose and cymose components of the thyrse. Loss of functional FvTFL1 reduces the number of lateral branches of the main axis and iterations in the lateral branches but does not affect their cymose pattern. These changes can be enhanced or compensated by altering FvFT1 expression. We complement our experimental findings with a computational model that captures inflorescence development using a small set of rules. The model highlights the distinct regulation of the fate of the primary and higher-order meristems, and explains the phenotypic diversity among inflorescences in terms of heterochrony resulting from the opposite action of FvTFL1 and FvFT1 within the thyrse framework. Our results represent a detailed analysis of thyrse architecture development at the meristematic and molecular levels.
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Affiliation(s)
- Sergei Lembinen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, PO Box 27, Helsinki FIN-00014, Finland
| | - Mikolaj Cieslak
- Department of Computer Science, University of Calgary, Calgary, AB, Canada T2N 1N4
| | - Teng Zhang
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, PO Box 27, Helsinki FIN-00014, Finland
| | - Kathryn Mackenzie
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, PO Box 27, Helsinki FIN-00014, Finland
| | - Paula Elomaa
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, PO Box 27, Helsinki FIN-00014, Finland
| | | | - Timo Hytönen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, PO Box 27, Helsinki FIN-00014, Finland
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Genome-Wide Identification of MADS-Box Family Genes in Safflower ( Carthamus tinctorius L.) and Functional Analysis of CtMADS24 during Flowering. Int J Mol Sci 2023; 24:ijms24021026. [PMID: 36674539 PMCID: PMC9862418 DOI: 10.3390/ijms24021026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/14/2022] [Accepted: 12/27/2022] [Indexed: 01/07/2023] Open
Abstract
Safflower is an important economic crop with a plethora of industrial and medicinal applications around the world. The bioactive components of safflower petals are known to have pharmacological activity that promotes blood circulation and reduces blood stasis. However, fine-tuning the genetic mechanism of flower development in safflower is still required. In this study, we report the genome-wide identification of MADS-box transcription factors in safflower and the functional characterization of a putative CtMADS24 during vegetative and reproductive growth. In total, 77 members of MADS-box-encoding genes were identified from the safflower genome. The phylogenetic analysis divided CtMADS genes into two types and 15 subfamilies. Similarly, bioinformatic analysis, such as of conserved protein motifs, gene structures, and cis-regulatory elements, also revealed structural conservation of MADS-box genes in safflower. Furthermore, the differential expression pattern of CtMADS genes by RNA-seq data indicated that type II genes might play important regulatory roles in floral development. Similarly, the qRT-PCR analysis also revealed the transcript abundance of 12 CtMADS genes exhibiting tissue-specific expression in different flower organs. The nucleus-localized CtMADS24 of the AP1 subfamily was validated by transient transformation in tobacco using GFP translational fusion. Moreover, CtMADS24-overexpressed transgenic Arabidopsis exhibited early flowering and an abnormal phenotype, suggesting that CtMADS24 mediated the expression of genes involved in floral organ development. Taken together, these findings provide valuable information on the regulatory role of CtMADS24 during flower development in safflower and for the selection of important genes for future molecular breeding programs.
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Liu S, Magne K, Zhou J, Laude J, Dalmais M, Le Signor C, Bendahmane A, Thompson R, Couzigou JM, Ratet P. The transcriptional co-regulators NBCL1 and NBCL2 redundantly coordinate aerial organ development and root nodule identity in legumes. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:194-213. [PMID: 36197099 DOI: 10.1093/jxb/erac389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
Medicago truncatula NODULE ROOT1 (MtNOOT1) and Pisum sativum COCHLEATA1 (PsCOCH1) are orthologous genes belonging to the NOOT-BOP-COCH-LIKE (NBCL) gene family which encodes key transcriptional co-regulators of plant development. In Mtnoot1 and Pscoch1 mutants, the development of stipules, flowers, and symbiotic nodules is altered. MtNOOT2 and PsCOCH2 represent the single paralogues of MtNOOT1 and PsCOCH1, respectively. In M. truncatula, MtNOOT1 and MtNOOT2 are both required for the establishment and maintenance of symbiotic nodule identity. In legumes, the role of NBCL2 in above-ground development is not known. To better understand the roles of NBCL genes in legumes, we used M. truncatula and P. sativum nbcl mutants, isolated a knockout mutant for the PsCOCH2 locus and generated Pscoch1coch2 double mutants in P. sativum. Our work shows that single Mtnoot2 and Pscoch2 mutants develop wild-type stipules, flowers, and symbiotic nodules. However, the number of flowers was increased and the pods and seeds were smaller compared to the wild type. Furthermore, in comparison to the corresponding nbcl1 single mutants, both the M. truncatula and P. sativum nbcl double mutants show a drastic alteration in stipule, inflorescence, flower, and nodule development. Remarkably, in both M. truncatula and P. sativum nbcl double mutants, stipules are transformed into a range of aberrant leaf-like structures.
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Affiliation(s)
- Shengbin Liu
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190, Gif sur Yvette, France
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, 91190, Gif sur Yvette, France
| | - Kévin Magne
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190, Gif sur Yvette, France
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, 91190, Gif sur Yvette, France
| | - Jing Zhou
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPS, Toulouse INP, 31320, Auzeville Tolosane, France
| | - Juliette Laude
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190, Gif sur Yvette, France
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, 91190, Gif sur Yvette, France
| | - Marion Dalmais
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190, Gif sur Yvette, France
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, 91190, Gif sur Yvette, France
| | - Christine Le Signor
- Agroécologie, AgroSup Dijon, Institut National de la Recherche Agronomique (INRAE), Université Bourgogne Franche-Comté, 21000, Dijon, France
| | - Abdelhafid Bendahmane
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190, Gif sur Yvette, France
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, 91190, Gif sur Yvette, France
| | - Richard Thompson
- Agroécologie, AgroSup Dijon, Institut National de la Recherche Agronomique (INRAE), Université Bourgogne Franche-Comté, 21000, Dijon, France
| | - Jean-Malo Couzigou
- Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPS, Toulouse INP, 31320, Auzeville Tolosane, France
| | - Pascal Ratet
- Université Paris-Saclay, CNRS, INRAE, Univ Evry, Institute of Plant Sciences Paris-Saclay (IPS2), 91190, Gif sur Yvette, France
- Institute of Plant Sciences Paris-Saclay (IPS2), Université de Paris, 91190, Gif sur Yvette, France
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Serra-Picó M, Hecht V, Weller JL, Benlloch R, Madueño F. Identification and characterization of putative targets of VEGETATIVE1/FULc, a key regulator of development of the compound inflorescence in pea and related legumes. FRONTIERS IN PLANT SCIENCE 2022; 13:765095. [PMID: 36212341 PMCID: PMC9533771 DOI: 10.3389/fpls.2022.765095] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 07/01/2022] [Indexed: 06/16/2023]
Abstract
Inflorescence architecture contributes to essential plant traits. It determines plant shape, contributing to morphological diversity, and also determines the position and number of flowers and fruits produced by the plant, thus influencing seed yield. Most legumes have compound inflorescences, where flowers are produced in secondary inflorescences (I2), formed at the flanks of the main primary inflorescence (I1), in contrast to simple inflorescences of plants like Arabidopsis, in which flowers are directly formed on the I1. The pea VEGETATIVE1/FULc (VEG1) gene, and its homologs in other legumes, specify the formation of the I2 meristem, a function apparently restricted to legumes. To understand the control of I2 development, it is important to identify the genes working downstream of VEG1. In this study, we adopted a novel strategy to identify genes expressed in the I2 meristem, as potential regulatory targets of VEG1. To identify pea I2-meristem genes, we compared the transcriptomes of inflorescence apices from wild-type and mutants affected in I2 development, such as proliferating inflorescence meristems (pim, with more I2 meristems), and veg1 and vegetative2 (both without I2 meristems). Analysis of the differentially expressed genes using Arabidopsis genome databases combined with RT-qPCR expression analysis in pea allowed the selection of genes expressed in the pea inflorescence apex. In situ hybridization of four of these genes showed that all four genes are expressed in the I2 meristem, proving our approach to identify I2-meristem genes was successful. Finally, analysis by VIGS (virus-induced gene silencing) in pea identified one gene, PsDAO1, whose silencing leads to small plants, and another gene, PsHUP54, whose silencing leads to plants with very large stubs, meaning that this gene controls the activity of the I2 meristem. PsHUP54-VIGS plants are also large and, more importantly, produce large pods with almost double the seeds as the control. Our study shows a new useful strategy to isolate I2-meristem genes and identifies a novel gene, PsHUP54, which seems to be a promising tool to improve yield in pea and in other legumes.
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Affiliation(s)
- Marcos Serra-Picó
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas - Universidad Politécnica de Valencia, Campus Universidad Politécnica de Valencia, Valencia, Spain
| | - Valérie Hecht
- School of Biological Sciences, University of Hobart, Hobart, TAS, Australia
| | - James L. Weller
- School of Biological Sciences, University of Hobart, Hobart, TAS, Australia
| | - Reyes Benlloch
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas - Universidad Politécnica de Valencia, Campus Universidad Politécnica de Valencia, Valencia, Spain
- Departamento de Biología Vegetal, Facultad de Farmacia, Universidad de Valencia, Valencia, Spain
| | - Francisco Madueño
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas - Universidad Politécnica de Valencia, Campus Universidad Politécnica de Valencia, Valencia, Spain
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Caballo C, Berbel A, Ortega R, Gil J, Millán T, Rubio J, Madueño F. The SINGLE FLOWER (SFL) gene encodes a MYB transcription factor that regulates the number of flowers produced by the inflorescence of chickpea. THE NEW PHYTOLOGIST 2022; 234:827-836. [PMID: 35122280 PMCID: PMC9314632 DOI: 10.1111/nph.18019] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 01/12/2022] [Indexed: 05/07/2023]
Abstract
Legumes usually have compound inflorescences, where flowers/pods develop from secondary inflorescences (I2), formed laterally at the primary inflorescence (I1). Number of flowers per I2, characteristic of each legume species, has important ecological and evolutionary relevance as it determines diversity in inflorescence architecture; moreover, it is also agronomically important for its potential impact on yield. Nevertheless, the genetic network controlling the number of flowers per I2 is virtually unknown. Chickpea (Cicer arietinum) typically produces one flower per I2 but single flower (sfl) mutants produce two (double-pod phenotype). We isolated the SFL gene by mapping the sfl-d mutation and identifying and characterising a second mutant allele. We analysed the effect of sfl on chickpea inflorescence ontogeny with scanning electron microscopy and studied the expression of SFL and meristem identity genes by RNA in situ hybridisation. We show that SFL corresponds to CaRAX1/2a, which codes a MYB transcription factor specifically expressed in the I2 meristem. Our findings reveal SFL as a central factor controlling chickpea inflorescence architecture, acting in the I2 meristem to regulate the length of the period for which it remains active, and therefore determining the number of floral meristems that it can produce.
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Affiliation(s)
- Cristina Caballo
- Área de Mejora y BiotecnologíaIFAPAAlameda del Obispo14080CórdobaSpain
| | - Ana Berbel
- Instituto de Biología Molecular y Celular de PlantasCSIC‐UPVCampus de Vera46022ValenciaSpain
| | - Raúl Ortega
- School of Natural SciencesUniversity of TasmaniaHobart7001TasmaniaAustralia
| | - Juan Gil
- Department of Genetics ETSIAMUniversity of Córdoba14071CórdobaSpain
| | - Teresa Millán
- Department of Genetics ETSIAMUniversity of Córdoba14071CórdobaSpain
| | - Josefa Rubio
- Área de Mejora y BiotecnologíaIFAPAAlameda del Obispo14080CórdobaSpain
| | - Francisco Madueño
- Instituto de Biología Molecular y Celular de PlantasCSIC‐UPVCampus de Vera46022ValenciaSpain
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Functional Conservation and Divergence of Five AP1/FUL-like Genes in Marigold ( Tagetes erecta L.). Genes (Basel) 2021; 12:genes12122011. [PMID: 34946960 PMCID: PMC8700864 DOI: 10.3390/genes12122011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022] Open
Abstract
Members of AP1/FUL subfamily genes play an essential role in the regulation of floral meristem transition, floral organ identity, and fruit ripping. At present, there have been insufficient studies to explain the function of the AP1/FUL-like subfamily genes in Asteraceae. Here, we cloned two euAP1 clade genes TeAP1-1 and TeAP1-2, and three euFUL clade genes TeFUL1, TeFUL2, and TeFUL3 from marigold (Tagetes erecta L.). Expression profile analysis demonstrated that TeAP1-1 and TeAP1-2 were mainly expressed in receptacles, sepals, petals, and ovules. TeFUL1 and TeFUL3 were expressed in flower buds, stems, and leaves, as well as reproductive tissues, while TeFUL2 was mainly expressed in flower buds and vegetative tissues. Overexpression of TeAP1-2 or TeFUL2 in Arabidopsis resulted in early flowering, implying that these two genes might regulate the floral transition. Yeast two-hybrid analysis indicated that TeAP1/FUL proteins only interacted with TeSEP proteins to form heterodimers and that TeFUL2 could also form a homodimer. In general, TeAP1-1 and TeAP1-2 might play a conserved role in regulating sepal and petal identity, similar to the functions of MADS-box class A genes, while TeFUL genes might display divergent functions. This study provides a theoretical basis for the study of AP1/FUL-like genes in Asteraceae species.
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Cai Y, Wang L, Ogutu CO, Yang Q, Luo B, Liao L, Zheng B, Zhang R, Han Y. The MADS-box gene PpPI is a key regulator of the double-flower trait in peach. PHYSIOLOGIA PLANTARUM 2021; 173:2119-2129. [PMID: 34537956 DOI: 10.1111/ppl.13561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 09/01/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
Double flower is an invaluable trait in ornamental peach, but the mechanism underlying its development remains largely unknown. Here, we report the roles of ABCE model genes in double flower development in peach. A total of nine ABCE regulatory genes, including eight MADS-box genes and one AP2/EREBP gene, were identified in the peach genome. Subcellular localization assay showed that all the ABCE proteins were localized in the nucleus. Four genes, PpAP1, PpAP3, PpSEP3, and PpPI, showed a difference in expression levels between single and double flowers. Ectopic overexpression of PpPI increased petal number in Arabidopsis, while transgenic lines overexpressing PpAP3 or PpSEP3 were morphologically similar to wild-type. Ectopic overexpression of PpAP1 resulted in a significant decrease in the number of basal leaves and caused early flowering. These results suggest that PpPI is likely crucial for double flower development in peach. In addition, double flowers have petaloid sepals and stamens, and single flower could occasionally change to be double flower by converting stamens to petals in peach, suggesting that the double-flower trait is likely to have evolved from an ancestral single-flower structure. Our results provide new insights into mechanisms underlying the double-flower trait in peach.
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Affiliation(s)
- Yaming Cai
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- Hubei Hongshan Laboratory, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lu Wang
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- Hubei Hongshan Laboratory, Wuhan, China
| | - Collins Otieno Ogutu
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
| | - Qiurui Yang
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Binwen Luo
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Liao Liao
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- Hubei Hongshan Laboratory, Wuhan, China
| | - Beibei Zheng
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- Hubei Hongshan Laboratory, Wuhan, China
| | - Ruoxi Zhang
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- Hubei Hongshan Laboratory, Wuhan, China
| | - Yuepeng Han
- CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, China
- Hubei Hongshan Laboratory, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
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Zhang P, Liu H, Mysore KS, Wen J, Meng Y, Lin H, Niu L. MtFDa is essential for flowering control and inflorescence development in Medicago truncatula. JOURNAL OF PLANT PHYSIOLOGY 2021; 260:153412. [PMID: 33845341 DOI: 10.1016/j.jplph.2021.153412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/28/2021] [Accepted: 03/28/2021] [Indexed: 06/12/2023]
Abstract
Flowering plants display a vast diversity of flowering time and inflorescence architecture, which plays an important role in determining seed yield and fruit production. However, the molecular mechanism underlying the flowering control and compound inflorescence development, especially in legumes, remain to be elucidated. Here, we reported the identification of MtFDa, an essential regulator of flowering in the model legume Medicago truncatula. Mutation of MtFDa, led to the late flowering, abnormal secondary inflorescences as well as severe floral organ defects. Biochemical and molecular analyses revealed that MtFDa physically interacts with M. truncaula FLOWERING LOCUS T homolog, MtFTa1, a key regulator of Medicago flowering time, and this interaction facilitates MtFDa's function in activating the expression of MtSOC1a. Moreover, we demonstrated that MtFDa may affect secondary inflorescence development via regulating MtFULc expression in M. truncatula. Our findings help elucidate the mechanism of MtFDa-mediated regulation of flowering time and inflorescence development and provide insights into understanding the genetic regulatory network underlying complex productive development in legumes.
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Affiliation(s)
- Pengcheng Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Huan Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | | | - Jiangqi Wen
- Noble Research Institute, Ardmore, OK, 73401, USA
| | - Yingying Meng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Hao Lin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Lifang Niu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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10
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Zhang P, Wang R, Wang X, Mysore KS, Wen J, Meng Y, Gu X, Niu L, Lin H. MtFULc controls inflorescence development by directly repressing MtTFL1 in Medicago truncatula. JOURNAL OF PLANT PHYSIOLOGY 2021; 256:153329. [PMID: 33310391 DOI: 10.1016/j.jplph.2020.153329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/17/2020] [Accepted: 11/17/2020] [Indexed: 06/12/2023]
Abstract
Flowering plants display a vast diversity of inflorescence architecture, which plays an important role in determining seed yield and fruit production. Unlike the model eudicot Arabidopsis thaliana that has simple inflorescences, most legume plants have compound types of inflorescences. Recent studies in the model legume species Pisum sativum and Medicago truncatula showed that the MADS-box transcription factors VEGETATIVE1/PsFRUITFULc/MtFRUITFULc (VEG1/PsFULc and MtFULc) are essential for the development of compound inflorescences by specifying the secondary inflorescence meristem identity. In this study, we report the isolation and characterization of two new mtfulc alleles by screening the M. truncatula Tnt1 insertion mutant collection. We found that MtFULc specifies M. truncatula secondary inflorescence meristem identity in a dose-dependent manner. Biochemical analysis and chromatin immunoprecipitation (ChIP) assays revealed that MtFULc acts as a transcriptional repressor to directly repress the expression of MtTFL1 through its promoter and 3' intergenic region. Comprehensive genetic analysis suggest MtFULc coordinates with the primary inflorescence meristem maintainer MtTFL1 and floral meristem regulator MtPIM to control M. truncatula inflorescence development. Our findings help to elucidate the mechanism of MtFULc-mediated regulation of secondary inflorescence meristem identity and provide insights into understanding the genetic regulatory network underlying compound inflorescence development in legumes.
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Affiliation(s)
- Pengcheng Zhang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Ruiliang Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; College of Life Science, Shanxi Agriculture University, Taigu 030801, China
| | - Xingchun Wang
- College of Life Science, Shanxi Agriculture University, Taigu 030801, China
| | | | - Jiangqi Wen
- Noble Research Institute, Ardmore, Oklahoma 73401, USA
| | - Yingying Meng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xiaofeng Gu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Lifang Niu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Hao Lin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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11
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Dzyubenko NI, Dzyubenko EA. Мutants of inflorescence development in alfalfa (Medicago sativa L.). Vavilovskii Zhurnal Genet Selektsii 2019. [DOI: 10.18699/vj19.543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- N. I. Dzyubenko
- Federal Research Center the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR)
| | - E. A. Dzyubenko
- Federal Research Center the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR)
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12
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Zhang S, Lu S, Yi S, Han H, Zhou Q, Cai F, Bao M, Liu G. Identification and characterization of FRUITFULL-like genes from Platanus acerifolia, a basal eudicot tree. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 280:206-218. [PMID: 30823999 DOI: 10.1016/j.plantsci.2018.11.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 09/18/2018] [Accepted: 11/26/2018] [Indexed: 05/26/2023]
Abstract
The function of euAP1 and euFUL in AP1/FUL lineage have been well characterized in core eudicots, and they play common and distinct roles in plant development. However, the evolution and function of FUL-like genes is poorly understood in basal eudicots. In this study, we identified three FUL-like genes PlacFL1/2/3 from London plane (Platanus acerifolia). Sequence alignment and phylogenetic analysis indicated that PlacFL1/2/3 are AP1/FUL orthologs and encoded proteins containing FUL motif and paleoAP1 motif. Quantitative real-time PCR (qRT-PCR) analysis showed that PlacFL1/2/3 were expressed in both vegetative and reproductive tissues, but with distinct spatiotemporal patterns. In contrast to PlacFL1 and PlacFL3, PlacFL2 exhibited higher expression levels and broader expression regions, and that the expression of PlacFL2 gene showed a decreasing and increasing tendency in subpetiolar buds during dormancy induction and breaking, respectively. Overexpression of PlacFLs in Arabidopsis and PlacFL3 in tobacco resulted in early flowering, as well as early termination of inflorescence meristems for transgenic Arabidopsis plants. The expression changes of flowering time and flower meristem identity genes in transgenic Arabidopsis lines with different PlacFLs suggested that PlacFL2 and PlacFL3 may regulate different downstream genes to perform divergent functions. Yeast two-hybrid analysis indicated that PlacFLs interacted strongly with PlacSEP proteins, and PlacFL3 instead of PlacFL1 and PlacFL2 could also form a homodimer and interact with D-class proteins. Our results suggest that PlacFLs may play conserved functions in regulating flowering and flower development, and PlacFL2 might also be involved in dormancy regulation. The research helps us to understand the functional evolution of FUL-like genes in basal eudicots, especially in perennial woody species.
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Affiliation(s)
- Sisi Zhang
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Key Laboratory of Urban Agriculture in Central China, Ministry of Agriculture, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Shizishan Street No. 1, Wuhan, 430070, China; Wuhan Institute of Landscape Architecture, Peace Avenue No. 1240, Wuhan, 430081, China
| | - Shunjiao Lu
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Key Laboratory of Urban Agriculture in Central China, Ministry of Agriculture, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Shizishan Street No. 1, Wuhan, 430070, China
| | - Shuangshuang Yi
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Key Laboratory of Urban Agriculture in Central China, Ministry of Agriculture, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Shizishan Street No. 1, Wuhan, 430070, China
| | - Hongji Han
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Key Laboratory of Urban Agriculture in Central China, Ministry of Agriculture, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Shizishan Street No. 1, Wuhan, 430070, China
| | - Qin Zhou
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Key Laboratory of Urban Agriculture in Central China, Ministry of Agriculture, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Shizishan Street No. 1, Wuhan, 430070, China
| | - Fangfang Cai
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Key Laboratory of Urban Agriculture in Central China, Ministry of Agriculture, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Shizishan Street No. 1, Wuhan, 430070, China
| | - Manzhu Bao
- Key Laboratory of Horticultural Plant Biology, Ministry of Education, Key Laboratory of Urban Agriculture in Central China, Ministry of Agriculture, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Shizishan Street No. 1, Wuhan, 430070, China
| | - Guofeng Liu
- Guangzhou Institute of Forestry and Landscape Architecture, Guangzhou, 510405, China.
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Shah S, Karunarathna NL, Jung C, Emrani N. An APETALA1 ortholog affects plant architecture and seed yield component in oilseed rape (Brassica napus L.). BMC PLANT BIOLOGY 2018; 18:380. [PMID: 30594150 PMCID: PMC6310979 DOI: 10.1186/s12870-018-1606-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 12/17/2018] [Indexed: 05/18/2023]
Abstract
BACKGROUND Increasing the productivity of rapeseed as one of the widely cultivated oil crops in the world is of upmost importance. As flowering time and plant architecture play a key role in the regulation of rapeseed yield, understanding the genetic mechanism underlying these traits can boost the rapeseed breeding. Meristem identity genes are known to have pleiotropic effects on plant architecture and seed yield in various crops. To understand the function of one of the meristem identity genes, APETALA1 (AP1) in rapeseed, we performed phenotypic analysis of TILLING mutants under greenhouse conditions. Three stop codon mutant families carrying a mutation in Bna.AP1.A02 paralog were analyzed for different plant architecture and seed yield-related traits. RESULTS It was evident that stop codon mutation in the K domain of Bna.AP1.A02 paralog caused significant changes in flower morphology as well as plant architecture related traits like plant height, branch height, and branch number. Furthermore, yield-related traits like seed yield per plant and number of seeds per plants were also significantly altered in the same mutant family. Apart from phenotypic changes, stop codon mutation in K domain of Bna.AP1.A02 paralog also altered the expression of putative downstream target genes like Bna.TFL1 and Bna.FUL in shoot apical meristem (SAM) of rapeseed. Mutant plants carrying stop codon mutations in the COOH domain of Bna.AP1.A02 paralog did not have a significant effect on plant architecture, yield-related traits or the expression of the downstream targets. CONCLUSIONS We found that Bna.AP1.A02 paralog has pleiotropic effect on plant architecture and yield-related traits in rapeseed. The allele we found in the current study with a beneficial effect on seed yield can be incorporated into rapeseed breeding pool to develop new varieties.
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Affiliation(s)
- Smit Shah
- Plant Breeding Institute, Christian-Albrechts-University of Kiel, Olshausenstr. 40, 24098 Kiel, Germany
| | - Nirosha L. Karunarathna
- Plant Breeding Institute, Christian-Albrechts-University of Kiel, Olshausenstr. 40, 24098 Kiel, Germany
| | - Christian Jung
- Plant Breeding Institute, Christian-Albrechts-University of Kiel, Olshausenstr. 40, 24098 Kiel, Germany
| | - Nazgol Emrani
- Plant Breeding Institute, Christian-Albrechts-University of Kiel, Olshausenstr. 40, 24098 Kiel, Germany
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Liu J, Li CQ, Dong Y, Yang X, Wang YZ. Dosage imbalance of B- and C-class genes causes petaloid-stamen relating to F 1 hybrid variation. BMC PLANT BIOLOGY 2018; 18:341. [PMID: 30526487 PMCID: PMC6286610 DOI: 10.1186/s12870-018-1562-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 11/22/2018] [Indexed: 06/09/2023]
Abstract
BACKGROUND Great advances have been achieved in our understanding of flower development and evolution since the establishment of the ABC model. However, it remains a challenge to define the exact context of organ identity in the component interactions of the ABC model. RESULTS Through hybridization, we detected a homeotic mutant in Petrocosmea (Gesneriaceae) uniquely displayed by the 'petaloid-stamen' in the third whorl with petal identity. Comparative Real-time PCR analyses demonstrate that both two B-class genes DEF2 and GLO are excessively expressed while the transcripts of the C-class gene PLE are reduced in the third floral whorl in the mutant compared to that in the wild-type F1 hybrids. Further allele-specific expression (ASE) analyses indicate that an allele-specific change in PgPLE might be responsible for up-regulation of both B-class genes and down-regulation of the C-class gene in the petaloid-stamen mutants. CONCLUSIONS Our findings suggest that the petaloid-stamen is consequent upon an evident dosage imbalance between B- and C-class products that is probably triggered by a cis-regulatory change. In addition, the genetic pathway for the floral organ identity might be in parallel with that for the floral symmetry. The extreme variation in hybrids further suggests that interspecific hybridization may represent a major factor for evolutionary innovation and diversification in plants.
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Affiliation(s)
- Jing Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Chao-Qun Li
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yang Dong
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093 China
| | - Xia Yang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093 China
| | - Yin-Zheng Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
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15
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Cheng X, Li G, Tang Y, Wen J. Dissection of genetic regulation of compound inflorescence development in Medicago truncatula. Development 2018; 145:dev.158766. [PMID: 29361570 DOI: 10.1242/dev.158766] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 01/02/2018] [Indexed: 12/15/2022]
Abstract
Development of inflorescence architecture is controlled by genetic regulatory networks. TERMINAL FLOWER1 (TFL1), APETALA1 (AP1), LEAFY (LFY) and FRUITFULL (FUL) are core regulators for inflorescence development. To understand the regulation of compound inflorescence development, we characterized mutants of corresponding orthologous genes, MtTFL1, MtAP1, SINGLE LEAFLET1 (SGL1) and MtFULc, in Medicago truncatula, and analyzed expression patterns of these genes. Results indicate that MtTFL1, MtFULc, MtAP1 and SGL1 play specific roles in identity determination of primary inflorescence meristems, secondary inflorescence meristems, floral meristems and common primordia, respectively. Double mutation of MtTFL1 and MtFULc transforms compound inflorescences to simple flowers, whereas single mutation of MtTFL1 changes the inflorescence branching pattern from monopodial to sympodial. Double mutant mtap1sgl1 completely loses floral meristem identity. We conclude that inflorescence architecture in M. truncatula is controlled by spatiotemporal expression of MtTFL1, MtFULc, MtAP1 and SGL1 through reciprocal repression. Although this regulatory network shares similarity with the pea model, it has specificity in regulating inflorescence architecture in Mtruncatula This study establishes M. truncatula as an excellent genetic model for understanding compound inflorescence development in related legume crops.
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Affiliation(s)
- Xiaofei Cheng
- Noble Research Institute, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Guifen Li
- Noble Research Institute, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Yuhong Tang
- Noble Research Institute, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
| | - Jiangqi Wen
- Noble Research Institute, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA
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Roque E, Gómez-Mena C, Ferrándiz C, Beltrán JP, Cañas LA. Functional Genomics and Genetic Control of Flower and Fruit Development in Medicago truncatula: An Overview. Methods Mol Biol 2018; 1822:273-290. [PMID: 30043310 DOI: 10.1007/978-1-4939-8633-0_18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A-, B-, and C-class genes code for MADS-box transcription factors required for floral organ identity in angiosperms. Other members of the family are also crucial to ensure proper carpel and fruit development. Development of genetic and genomic tools for Medicago truncatula has allowed its use as model system to study the genetic control of flower and fruit development in legumes. M. truncatula contains a single A-class gene, four B-function genes, and three C-class genes in its genome. This has made possible to do extensive functional characterization of these MADS-box transcription factors using gene expression analyses, protein-protein interactions, and forward and reverse genetic approaches. We have demonstrated the functions of these MADS-box transcription factors and the respective contributions of paralogous gene pairs to M. truncatula floral development. We have also defined the evolutionary outcomes of each duplicated pairs thus testing theoretical framework of several models about the evolution by gene duplication. Moreover, we have also studied the function of MADS-box fruit genes and how they may have contributed to the diversification of pod morphology within the Medicago genus. Our findings not only have contributed to increase knowledge in the field of the genetic control of flower and fruit development but also have provided a more complete understanding of the complexity of evolution by gene duplication and protein sequence diversification.
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Affiliation(s)
- Edelín Roque
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), Ciudad Politécnica de la Innovación Edf. 8E, C/ Ingeniero Fausto Elio s.n., Valencia, E-46011, Spain
| | - Concepción Gómez-Mena
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), Ciudad Politécnica de la Innovación Edf. 8E, C/ Ingeniero Fausto Elio s.n., Valencia, E-46011, Spain
| | - Cristina Ferrándiz
- Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), Ciudad Politécnica de la Innovación Edf. 8E, C/ Ingeniero Fausto Elio s.n., Valencia, E-46011, Spain
| | - José Pío Beltrán
- CSIC-UPV, Institute for Plant Cell and Molecular Biology(IBMCP), Valencia, Spain.
| | - Luis A Cañas
- CSIC-UPV, Institute for Plant Cell and Molecular Biology(IBMCP), Valencia, Spain.
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Abstract
Many researchers have sought along the last two decades a legume species that could serve as a model system for genetic studies to resolve specific developmental or metabolic processes that cannot be studied in other model plants. Nitrogen fixation, nodulation, compound leaf, inflorescence and plant architecture, floral development, pod formation, secondary metabolite biosynthesis, and other developmental and metabolic aspects are legume-specific or show important differences with those described in Arabidopsis thaliana, the most studied model plant. Mainly Medicago truncatula and Lotus japonicus were proposed in the 1990s as model systems due to their key attributes, diploid genome, autogamous nature, short generation times, small genome sizes, and both species can be readily transformed. After more than decade-long, the genome sequences of both species are essentially complete, and a series of functional genomics tools have been successfully developed and applied. Mutagens that cause insertions or deletions are being used in these model systems because these kinds of DNA rearrangements are expected to assist in the isolation of the corresponding genes by Target-Induced Local Lesions IN Genomes (TILLING) approaches. Different M. truncatula mutants have been obtained following γ-irradiation or fast neutron bombardment (FNB), ethyl-nitrosourea (ENU) or ethyl-methanesulfonate (EMS) treatments, T-DNA and activation tagging, use of the tobacco retrotransposon Tnt1 to produce insertional mutants, gene silencing by RNAi, and transient post-transcriptional gene silencing by virus-induced gene silencing (VIGS). Emerging technologies of targeted mutagenesis and gene editing, such as the CRISPR-Cas9 system, could open a new era in this field. Functional genomics tools and phenotypic analyses of several mutants generated in M. truncatula have been essential to better understand differential aspects of legumes development and metabolism.
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Affiliation(s)
- Luis A Cañas
- CSIC-UPV, Institute for Plant Cell and Molecular Biology (IBMCP), Valencia, Spain.
| | - José Pío Beltrán
- CSIC-UPV, Institute for Plant Cell and Molecular Biology (IBMCP), Valencia, Spain
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18
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Sawettalake N, Bunnag S, Wang Y, Shen L, Yu H. DOAP1 Promotes Flowering in the Orchid Dendrobium Chao Praya Smile. FRONTIERS IN PLANT SCIENCE 2017; 8:400. [PMID: 28386268 PMCID: PMC5362595 DOI: 10.3389/fpls.2017.00400] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Accepted: 03/08/2017] [Indexed: 05/02/2023]
Abstract
APETALA1 (AP1) encodes a key MADS-box transcription factor that specifies the floral meristem identity on the flank of the inflorescence meristem, and determines the identity of perianth floral organs in the model plant Arabidopsis thaliana. Orchids are members of the Orchidaceae, one of the largest families of angiosperms. Although the expression patterns of a few AP1-like genes in orchids have been reported, their actual functions in orchid reproductive development are so far largely unknown. In this study, we isolated and characterized an AP1 ortholog, DOAP1, from Dendrobium Chao Praya Smile. DOAP1 was highly expressed in reproductive tissues, including inflorescence apices and flowers at various developmental stages. Overexpression of DOAP1 resulted in early flowering in Arabidopsis, and was able to rescue the floral organ defects of Arabidopsis ap1 mutants. Moreover, we successfully created transgenic Dendrobium Chao Praya Smile orchids overexpressing DOAP1, which displayed earlier flowering and earlier termination of inflorescence meristems into floral meristems than wild-type orchids. Our results demonstrate that DOAP1 plays an evolutionarily conserved role in promoting flowering and floral meristem specification in the Orchidaceae family.
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Affiliation(s)
- Nunchanoke Sawettalake
- Department of Biology, Faculty of Science, Khon Kaen UniversityKhon Kaen, Thailand
- Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of SingaporeSingapore, Singapore
| | - Sumontip Bunnag
- Department of Biology, Faculty of Science, Khon Kaen UniversityKhon Kaen, Thailand
| | - Yanwen Wang
- Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of SingaporeSingapore, Singapore
| | - Lisha Shen
- Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of SingaporeSingapore, Singapore
| | - Hao Yu
- Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of SingaporeSingapore, Singapore
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19
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Tao YB, He LL, Niu L, Xu ZF. Isolation and characterization of the Jatropha curcas APETALA1 (JcAP1) promoter conferring preferential expression in inflorescence buds. PLANTA 2016; 244:467-478. [PMID: 27095108 DOI: 10.1007/s00425-016-2519-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Accepted: 04/04/2016] [Indexed: 06/05/2023]
Abstract
The 1.5 kb JcAP1 promoter from the biofuel plant Jatropha curcas is predominantly active in the inflorescence buds of transgenic plants, in which the -1313/-1057 region is essential for maintaining the activity. Arabidopsis thaliana APETALA1 (AP1) is a MADS-domain transcription factor gene that functions primarily in flower development. We isolated a homolog of AP1 from Jatropha curcas (designated JcAP1), which was shown to exhibit flower-specific expression in Jatropha. JcAP1 is first expressed in inflorescence buds and continues to be primarily expressed in the sepals. We isolated a 1.5 kb JcAP1 promoter and evaluated its activity in transgenic Arabidopsis and Jatropha using the β-glucuronidase (GUS) reporter gene. In transgenic Arabidopsis and Jatropha, the inflorescence buds exhibited notable GUS activity, whereas the sepals did not. Against expectations, the JcAP1 promoter was active in the anthers of Arabidopsis and Jatropha and was highly expressed in Jatropha seeds. An analysis of promoter deletions in transgenic Arabidopsis revealed that deletion of the -1313/-1057 region resulted in loss of JcAP1 promoter activity in the inflorescence buds and increased activity in the anthers. These results suggested that some regulatory sequences in the -1313/-1057 region are essential for maintaining promoter activity in inflorescence buds and can partly suppress activity in the anthers. Based on these findings, we hypothesized that other elements located upstream of the 1.5 kb JcAP1 promoter may be required for flower-specific activation. The JcAP1 promoter characterized in this study can be used to drive transgene expression in both the inflorescence buds and seeds of Jatropha.
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Affiliation(s)
- Yan-Bin Tao
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China
| | - Liang-Liang He
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Longjian Niu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Zeng-Fu Xu
- Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, 666303, Yunnan, China.
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20
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Zumajo-Cardona C, Pabón-Mora N. Evolution of the APETALA2 Gene Lineage in Seed Plants. Mol Biol Evol 2016; 33:1818-32. [PMID: 27030733 DOI: 10.1093/molbev/msw059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Gene duplication is a fundamental source of functional evolutionary change and has been associated with organismal diversification and the acquisition of novel features. The APETALA2/ETHYLENE RESPONSIVE ELEMENT-BINDING FACTOR (AP2/ERF) genes are exclusive to vascular plants and have been classified into the AP2-like and ERF-like clades. The AP2-like clade includes the AINTEGUMENTA (ANT) and the euAPETALA2 (euAP2) genes, both regulated by miR172 Arabidopsis has two paralogs in the euAP2 clade, namely APETALA2 (AP2) and TARGET OF EAT3 (TOE3) that control flowering time, meristem determinacy, sepal and petal identity and fruit development. euAP2 genes are likely functionally divergent outside Brassicaceae, as they control fruit development in tomato, and regulate inflorescence meristematic activity in maize. We studied the evolution and expression patterns of euAP2/TOE3 genes to assess large scale and local duplications and evaluate protein motifs likely related with functional changes across seed plants. We sampled euAP2/TOE3 genes from vascular plants and have found three major duplications and a few taxon-specific duplications. Here, we report conserved and new motifs across euAP2/TOE3 proteins and conclude that proteins predating the Brassicaceae duplication are more similar to AP2 than TOE3. Expression data show a shift from restricted expression in leaves, carpels, and fruits in non-core eudicots and asterids to a broader expression of euAP2 genes in leaves, all floral organs and fruits in rosids. Altogether, our data show a functional trend where the canonical A-function (sepal and petal identity) is exclusive to Brassicaceae and it is likely not maintained outside of rosids.
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Jia Z, Jiang B, Gao X, Yue Y, Fei Z, Sun H, Wu C, Sun S, Hou W, Han T. GmFULa, a FRUITFULL homolog, functions in the flowering and maturation of soybean. PLANT CELL REPORTS 2015; 34:121-32. [PMID: 25326369 DOI: 10.1007/s00299-014-1693-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 09/17/2014] [Accepted: 10/07/2014] [Indexed: 05/04/2023]
Abstract
KEY MESSAGE A FRUITFULL homolog GmFULa was cloned and found to play roles in the flowering and maturation of soybean. Soybean varieties exhibit great diversity in terms of flowering and maturation due to differences in their photoperiodic responses. The underlying mechanism remains unclear despite the fact that some upstream flowering genes have been studied. FRUITFULL (FUL) genes are one group of downstream flowering genes known to have major roles in reproductive transition, floral meristem identity, and floral organ identity. However, FUL homologs and their functions are poorly understood in soybean. Here, a soybean FUL homolog was cloned from the late-maturing photoperiod-sensitive soybean variety Zigongdongdou (ZGDD) and designated GmFULa. In ZGDD, GmFULa exhibited a terminal-preferential expression pattern, with higher expression in the root and shoot apices than in the middle parts. Diurnal rhythm analysis revealed that photoperiod regulates the GmFULa expression level but does not alter its diurnal rhythm. ZGDD was maintained under different photoperiod conditions (long day, LD; short day, SD; LD after 13 short days, SD13-LD) to assess GmFULa expression in newly expanded leaves and in the shoot apex. From this analysis, GmFULa expression was detected in the floral meristem, floral organs and their primordia; trifoliate leaves; and the inflorescence meristem, with the expression levels induced by SD and inhibited by LD. GmFULa expression was also associated with maturity in seven soybean varieties with different photoperiod sensitivities. Therefore, photoperiod conditions affect the expression level of GmFULa but not its diurnal rhythm. The gene plays pleiotropic roles in reproductive transition, flowering, and leaf development and is associated with maturity in soybean.
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Affiliation(s)
- Zhen Jia
- The National Key Facility for Crop Gene Resources and Genetic Improvement and MOA Key Lab of Soybean Biology (Beijing), Institute of Crop Science, The Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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Benlloch R, Berbel A, Ali L, Gohari G, Millán T, Madueño F. Genetic control of inflorescence architecture in legumes. FRONTIERS IN PLANT SCIENCE 2015; 6:543. [PMID: 26257753 PMCID: PMC4508509 DOI: 10.3389/fpls.2015.00543] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 07/06/2015] [Indexed: 05/18/2023]
Abstract
The architecture of the inflorescence, the shoot system that bears the flowers, is a main component of the huge diversity of forms found in flowering plants. Inflorescence architecture has also a strong impact on the production of fruits and seeds, and on crop management, two highly relevant agronomical traits. Elucidating the genetic networks that control inflorescence development, and how they vary between different species, is essential to understanding the evolution of plant form and to being able to breed key architectural traits in crop species. Inflorescence architecture depends on the identity and activity of the meristems in the inflorescence apex, which determines when flowers are formed, how many are produced and their relative position in the inflorescence axis. Arabidopsis thaliana, where the genetic control of inflorescence development is best known, has a simple inflorescence, where the primary inflorescence meristem directly produces the flowers, which are thus borne in the main inflorescence axis. In contrast, legumes represent a more complex inflorescence type, the compound inflorescence, where flowers are not directly borne in the main inflorescence axis but, instead, they are formed by secondary or higher order inflorescence meristems. Studies in model legumes such as pea (Pisum sativum) or Medicago truncatula have led to a rather good knowledge of the genetic control of the development of the legume compound inflorescence. In addition, the increasing availability of genetic and genomic tools for legumes is allowing to rapidly extending this knowledge to other grain legume crops. This review aims to describe the current knowledge of the genetic network controlling inflorescence development in legumes. It also discusses how the combination of this knowledge with the use of emerging genomic tools and resources may allow rapid advances in the breeding of grain legume crops.
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Affiliation(s)
- Reyes Benlloch
- Molecular Genetics Department, Center for Research in Agricultural Genomics, Consortium CSIC-IRTA-UAB-UB, Parc de Recerca Universitat Autònoma de BarcelonaBarcelona, Spain
| | - Ana Berbel
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas – Universidad Politécnica de ValenciaValencia, Spain
| | - Latifeh Ali
- Departamento de Genética, Universidad de CórdobaCórdoba, Spain
| | - Gholamreza Gohari
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas – Universidad Politécnica de ValenciaValencia, Spain
| | - Teresa Millán
- Departamento de Genética, Universidad de CórdobaCórdoba, Spain
| | - Francisco Madueño
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas – Universidad Politécnica de ValenciaValencia, Spain
- *Correspondence: Francisco Madueño, Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas – Universidad Politécnica de Valencia, Avenida Los Naranjos s/n, Valencia 46022, Spain,
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McCarthy EW, Mohamed A, Litt A. Functional Divergence of APETALA1 and FRUITFULL is due to Changes in both Regulation and Coding Sequence. FRONTIERS IN PLANT SCIENCE 2015; 6:1076. [PMID: 26697035 PMCID: PMC4667048 DOI: 10.3389/fpls.2015.01076] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 11/17/2015] [Indexed: 05/21/2023]
Abstract
Gene duplications are prevalent in plants, and functional divergence subsequent to duplication may be linked with the occurrence of novel phenotypes in plant evolution. Here, we examine the functional divergence of Arabidopsis thaliana APETALA1 (AP1) and FRUITFULL (FUL), which arose via a duplication correlated with the origin of the core eudicots. Both AP1 and FUL play a role in floral meristem identity, but AP1 is required for the formation of sepals and petals whereas FUL is involved in cauline leaf and fruit development. AP1 and FUL are expressed in mutually exclusive domains but also differ in sequence, with unique conserved motifs in the C-terminal domains of the proteins that suggest functional differentiation. To determine whether the functional divergence of AP1 and FUL is due to changes in regulation or changes in coding sequence, we performed promoter swap experiments, in which FUL was expressed in the AP1 domain in the ap1 mutant and vice versa. Our results show that FUL can partially substitute for AP1, and AP1 can partially substitute for FUL; thus, the functional divergence between AP1 and FUL is due to changes in both regulation and coding sequence. We also mutated AP1 and FUL conserved motifs to determine if they are required for protein function and tested the ability of these mutated proteins to interact in yeast with known partners. We found that these motifs appear to play at best a minor role in protein function and dimerization capability, despite being strongly conserved. Our results suggest that the functional differentiation of these two paralogous key transcriptional regulators involves both differences in regulation and in sequence; however, sequence changes in the form of unique conserved motifs do not explain the differences observed.
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Affiliation(s)
- Elizabeth W. McCarthy
- Department of Botany and Plant Sciences, University of California, RiversideRiverside, CA, USA
| | - Abeer Mohamed
- Department of Agricultural Botany, Faculty of Agriculture (Saba Basha), Alexandria UniversityAlexandria, Egypt
| | - Amy Litt
- Department of Botany and Plant Sciences, University of California, RiversideRiverside, CA, USA
- *Correspondence: Amy Litt,
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Pabón-Mora N, Suárez-Baron H, Ambrose BA, González F. Flower Development and Perianth Identity Candidate Genes in the Basal Angiosperm Aristolochia fimbriata (Piperales: Aristolochiaceae). FRONTIERS IN PLANT SCIENCE 2015; 6:1095. [PMID: 26697047 PMCID: PMC4675851 DOI: 10.3389/fpls.2015.01095] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/22/2015] [Indexed: 05/21/2023]
Abstract
Aristolochia fimbriata (Aristolochiaceae: Piperales) exhibits highly synorganized flowers with a single convoluted structure forming a petaloid perianth that surrounds the gynostemium, putatively formed by the congenital fusion between stamens and the upper portion of the carpels. Here we present the flower development and morphology of A. fimbriata, together with the expression of the key regulatory genes that participate in flower development, particularly those likely controlling perianth identity. A. fimbriata is a member of the magnoliids, and thus gene expression detected for all ABCE MADS-box genes in this taxon, can also help to elucidate patterns of gene expression prior the independent duplications of these genes in eudicots and monocots. Using both floral development and anatomy in combination with the isolation of MADS-box gene homologs, gene phylogenetic analyses and expression studies (both by reverse transcription PCR and in situ hybridization), we present hypotheses on floral organ identity genes involved in the formation of this bizarre flower. We found that most MADS-box genes were expressed in vegetative and reproductive tissues with the exception of AfimSEP2, AfimAGL6, and AfimSTK transcripts that are only found in flowers and capsules but are not detected in leaves. Two genes show ubiquitous expression; AfimFUL that is found in all floral organs at all developmental stages as well as in leaves and capsules, and AfimAG that has low expression in leaves and is found in all floral organs at all stages with a considerable reduction of expression in the limb of anthetic flowers. Our results indicate that expression of AfimFUL is indicative of pleiotropic roles and not of a perianth identity specific function. On the other hand, expression of B-class genes, AfimAP3 and AfimPI, suggests their conserved role in stamen identity and corroborates that the perianth is sepal and not petal-derived. Our data also postulates an AGL6 ortholog as a candidate gene for sepal identity in the Aristolochiaceae and provides testable hypothesis for a modified ABCE model in synorganized magnoliid flowers.
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Affiliation(s)
- Natalia Pabón-Mora
- Instituto de Biología, Universidad de AntioquiaMedellín, Colombia
- The New York Botanical Garden, BronxNY, USA
- *Correspondence: Natalia Pabón-Mora,
| | | | | | - Favio González
- Instituto de Ciencias Naturales, Facultad de Ciencias, Universidad Nacional de ColombiaBogotá, Colombia
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Zheng T, Li S, Zang L, Dai L, Yang C, Qu GZ. Overexpression of two PsnAP1 genes from Populus simonii × P. nigra causes early flowering in transgenic tobacco and Arabidopsis. PLoS One 2014; 9:e111725. [PMID: 25360739 PMCID: PMC4216142 DOI: 10.1371/journal.pone.0111725] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 10/07/2014] [Indexed: 12/05/2022] Open
Abstract
In Arabidopsis, AP1 is a floral meristem identity gene and plays an important role in floral organ development. In this study, PsnAP1-1 and PsnAP1-2 were isolated from the male reproductive buds of poplar (Populus simonii × P. nigra), which are the orthologs of AP1 in Arabidopsis, by sequence analysis. Northern blot and qRT-PCR analysis showed that PsnAP1-1 and PsnAP1-2 exhibited high expression level in early inflorescence development of poplar. Subcellular localization showed the PsnAP1-1 and PsnAP1-2 proteins are localized in the nucleus. Overexpression of PsnAP1-1 and PsnAP1-2 in tobacco under the control of a CaMV 35S promoter significantly enhanced early flowering. These transgenic plants also showed much earlier stem initiation and higher rates of photosynthesis than did wild-type tobacco. qRT-PCR analysis further indicated that overexpression of PsnAP1-1 and PsnAP1-2 resulted in up-regulation of genes related to flowering, such as NtMADS4, NtMADS5 and NtMADS11. Overexpression of PsnAP1-1 and PsnAP1-2 in Arabidopsis also induced early flowering, but did not complement the ap1-10 floral morphology to any noticeable extent. This study indicates that PsnAP1-1 and PsnAP1-2 play a role in floral transition of poplar.
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Affiliation(s)
- Tangchun Zheng
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), Harbin, China
| | - Shuang Li
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), Harbin, China
| | - Lina Zang
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), Harbin, China
| | - Lijuan Dai
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), Harbin, China
| | - Chuanping Yang
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), Harbin, China
| | - Guan-Zheng Qu
- State Key Laboratory of Tree Genetics and Breeding (Northeast Forestry University), Harbin, China
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Ferrándiz C, Fourquin C. Role of the FUL-SHP network in the evolution of fruit morphology and function. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:4505-13. [PMID: 24482369 DOI: 10.1093/jxb/ert479] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Arabidopsis research in the last decade has started to unravel the genetic networks directing gynoecium and fruit patterning in this model species. Only recently, the work from several groups has also started to address the conservation of these networks in a wide number of species with very different fruit morphologies, and we are now beginning to understand how they might have evolved. This review summarizes recent advances in this field, focusing mainly on MADS-box genes with a well-known role in dehiscence zone development, while also discussing how these studies may contribute to expand our views on fruit evolution.
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Affiliation(s)
- Cristina Ferrándiz
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), UPV-CSIC, Av. de los Naranjos s/n 46022 Valencia, Spain
| | - Chloé Fourquin
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), UPV-CSIC, Av. de los Naranjos s/n 46022 Valencia, Spain
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Huang H, Wang S, Jiang J, Liu G, Li H, Chen S, Xu H. Overexpression of BpAP1 induces early flowering and produces dwarfism in Betula platyphylla × Betula pendula. PHYSIOLOGIA PLANTARUM 2014; 151:495-506. [PMID: 24200078 DOI: 10.1111/ppl.12123] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 09/27/2013] [Accepted: 10/27/2013] [Indexed: 05/04/2023]
Abstract
The involvement of APETALA1 (AP1) in the flowering transition has been the focus of much research. Here, we produced Betula platyphylla × Betula pendula (birch) lines that overexpressed BpAP1 using Agrobacterium-mediated transformation; we obtained five independent 35S::BpAP1 transgenic lines. Polymerase chain reaction (PCR), Southern, northern and western analyses were used to identify the transformants. As determined by quantitative real-time PCR (qRT-PCR), BpAP1 expression in roots, shoots, leaves and terminal buds of 35S::BpAP1 transgenic lines was significantly higher than that in the wild type (WT, P < 0.01). The average height of 2-year-old 35S::BpAP1 plants was significantly lower (41.17%) than that of non-transgenic plants. In the 35S::BpAP1 lines, inflorescences emerged successively beginning 2 months after transplanting. In addition, the length-diameter ratio of fully developed male and female inflorescences were both significantly less than those of the WT (P < 0.05), i.e. the morphological characteristic was stubby. The male inflorescences emerged early, with empty, draped anthers, and pollen was rarely produced, whereas the female floret structure was not different from WT. The pistils developed normally and could accept pollen, leading to the production of hybrid progeny (F1 ). F1 plants completed flowering within only 1 year after sowing. We demonstrate that BpAP1 can be inherited through sexual reproduction. Overexpression of BpAP1 caused early flowering and dwarfism; these lines had an obviously shortened juvenile phase. These results greatly increase our understanding of the mechanisms underlying the flowering transition and enhance genetic studies of birch traits, and they open up new possibilities for the breeding of birch and other woody plants.
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Affiliation(s)
- Haijiao Huang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China
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de Oliveira RR, Cesarino I, Mazzafera P, Dornelas MC. Flower development in Coffea arabica L.: new insights into MADS-box genes. PLANT REPRODUCTION 2014; 27:79-94. [PMID: 24715004 DOI: 10.1007/s00497-014-0242-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 03/24/2014] [Indexed: 05/27/2023]
Abstract
Coffea arabica L. shows peculiar characteristics during reproductive development, such as flowering asynchrony, periods of floral bud dormancy, mucilage secretion and epipetalous stamens. The MADS-box transcription factors are known to control several developmental processes in plants, including flower and fruit development. Significant differences are found among plant species regarding reproductive development and little is known about the role of MADS-box genes in Coffea reproductive development. Thus, we used anatomical and comparative molecular analyses to explore the flowering process in coffee. The main morphological changes during flower development in coffee were observed by optical and scanning electron microscopy. Flowering asynchrony seems to be related to two independent processes: the asynchronous development of distinct buds before the reproductive induction and the asynchronous development of floral meristems within each bud after the reproductive induction. A total of 23 C. arabica MADS-box genes were characterized by sequence comparison with putative Arabidopsis orthologs and their expression profiles were analyzed by RT-PCR in different tissues. The expression of the ABC model orthologs in Coffea during floral development was determined by in situ hybridization. The APETALA1 (AP1) ortholog is expressed only late in the perianth, which is also observed for the APETALA3 and TM6 orthologs. Conversely, the PISTILLATA ortholog is widely expressed in early stages, but restrict to stamens and carpels in later stages of flower development, while the expression of the AGAMOUS ortholog is always restricted to fertile organs. The AP1 and PISTILLATA orthologs are also expressed at specific floral organs, such as bracts and colleters, respectively, suggesting a potential role in the development of such structures. Altogether, the results from our comprehensive expression analyses showed significant differences between the spatiotemporal expression profiles of C. arabica MADS-box genes and their orthologs, which suggests differential functionalization in coffee. Moreover, these differences might also partially explain the particular characteristics of floral development in coffee, such as mucilage secretion and formation of epipetalous stamens.
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Affiliation(s)
- Raphael Ricon de Oliveira
- Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Cidade Universitária "Zeferino Vaz", Campinas, São Paulo, Brazil,
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Chen ZH, Jia FF, Hu JQ, Pang JL, Xu L, Wang LL. Virus-induced gene silencing of PEAM4 affects floral morphology by altering the expression pattern of PsSOC1a and PsPVP in pea. JOURNAL OF PLANT PHYSIOLOGY 2014; 171:148-53. [PMID: 24331430 DOI: 10.1016/j.jplph.2013.08.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Revised: 06/29/2013] [Accepted: 08/15/2013] [Indexed: 06/03/2023]
Abstract
pea-MADS4 (PEAM4) regulates floral morphology in Pisum sativum L., however, its molecular mechanisms still remain unclear. Virus-induced gene silencing (VIGS) is a recently developed reverse genetic approach that facilities an easier and more rapid study of gene functions. In this study, the PEAM4 gene was effectively silenced by VIGS using a pea early browning virus (PEBV) in wild type pea JI992. The infected plants showed abnormal phenotypes, as the floral organs, especially the sepals and petals changed in both size and shape, which made the corolla less closed. The petals changed in morphology and internal symmetry with, the stamens reduced and carpel dehisced. Larger sepals and longer tendrils with small cauline leaves appeared, with some sepals turning into bracts, and secondary inflorescences with fused floral organs were formed, indicating a flower-to-inflorescence change. The infected plants also displayed a delayed and prolonged flowering time. The PEAM4-VIGS plants with altered floral morphology were similar to the pim (proliferating inflorescence meristem) mutant and also mimicked the phenotypes of ap1 mutants in Arabidopsis. The expression pattern of the homologous genes PsSOC1a and PsSVP, which were involved in flowering time and florescence morphological control downstream of PEAM4, were analyzed by real-time RT-PCR and mRNA in situ hybridization. PsSOC1a and PsSVP were ectopically expressed and enhanced in the floral meristems from PEAM4-silenced plants. Our data suggests that PEAM4 may have a similar molecular mechanism as AtAP1, which inhibits the expression of PsSOC1a and PsSVP in the floral meristem from the early stages of flower development. As such, in this way PEAM4 plays a crucial role in maintaining floral organ identity and flower development in pea.
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Affiliation(s)
- Zhe-Hao Chen
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Fei-Fei Jia
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Jiang-Qin Hu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Ji-Liang Pang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Lei Xu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China
| | - Li-Lin Wang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, Zhejiang, China.
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Pabón-Mora N, Hidalgo O, Gleissberg S, Litt A. Assessing duplication and loss of APETALA1/FRUITFULL homologs in Ranunculales. FRONTIERS IN PLANT SCIENCE 2013; 4:358. [PMID: 24062757 PMCID: PMC3775002 DOI: 10.3389/fpls.2013.00358] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 08/23/2013] [Indexed: 05/03/2023]
Abstract
Gene duplication and loss provide raw material for evolutionary change within organismal lineages as functional diversification of gene copies provide a mechanism for phenotypic variation. Here we focus on the APETALA1/FRUITFULL MADS-box gene lineage evolution. AP1/FUL genes are angiosperm-specific and have undergone several duplications. By far the most significant one is the core-eudicot duplication resulting in the euAP1 and euFUL clades. Functional characterization of several euAP1 and euFUL genes has shown that both function in proper floral meristem identity, and axillary meristem repression. Independently, euAP1 genes function in floral meristem and sepal identity, whereas euFUL genes control phase transition, cauline leaf growth, compound leaf morphogenesis and fruit development. Significant functional variation has been detected in the function of pre-duplication basal-eudicot FUL-like genes, but the underlying mechanisms for change have not been identified. FUL-like genes in the Papaveraceae encode all functions reported for euAP1 and euFUL genes, whereas FUL-like genes in Aquilegia (Ranunculaceae) function in inflorescence development and leaf complexity, but not in flower or fruit development. Here we isolated FUL-like genes across the Ranunculales and used phylogenetic approaches to analyze their evolutionary history. We identified an early duplication resulting in the RanFL1 and RanFL2 clades. RanFL1 genes were present in all the families sampled and are mostly under strong negative selection in the MADS, I and K domains. RanFL2 genes were only identified from Eupteleaceae, Papaveraceae s.l., Menispermaceae and Ranunculaceae and show relaxed purifying selection at the I and K domains. We discuss how asymmetric sequence diversification, new motifs, differences in codon substitutions and likely protein-protein interactions resulting from this Ranunculiid-specific duplication can help explain the functional differences among basal-eudicot FUL-like genes.
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Affiliation(s)
- Natalia Pabón-Mora
- Grupo de Biotecnología, Instituto de Biología, Universidad de AntioquiaMedellín, Colombia
- The New York Botanical GardenBronx, NY, USA
| | - Oriane Hidalgo
- Laboratori de Botànica, Facultat de Farmàcia, Universitat de BarcelonaBarcelona, Spain
| | | | - Amy Litt
- The New York Botanical GardenBronx, NY, USA
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Pabón-Mora N, Sharma B, Holappa LD, Kramer EM, Litt A. The Aquilegia FRUITFULL-like genes play key roles in leaf morphogenesis and inflorescence development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 74:197-212. [PMID: 23294330 DOI: 10.1111/tpj.12113] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 12/19/2012] [Accepted: 01/02/2013] [Indexed: 05/03/2023]
Abstract
The APETALA1/FRUITFULL (AP1/FUL) MADS box transcription factors are best known for the role of AP1 in Arabidopsis sepal and petal identity, the canonical A function of the ABC model of flower development. However, this gene lineage underwent multiple duplication events during angiosperm evolution, providing different taxa with unique gene complements. One such duplication correlates with the origin of the core eudicots, and produced the euAP1 and euFUL clades. Together, euAP1 and euFUL genes function in proper floral meristem identity and repression of axillary meristem growth. Independently, euAP1 genes function in floral meristem and sepal identity, whereas euFUL genes control phase transition, cauline leaf growth and fruit development. To investigate the impact of the core eudicot duplication on the functional diversification of this gene lineage, we studied the role of pre-duplication FUL-like genes in columbine (Aquilegia coerulea). Our results show that AqcFL1 genes are broadly expressed in vegetative and reproductive meristems, leaves and flowers. Virus-induced gene silencing of the loci results in plants with increased branching, shorter inflorescences with fewer flowers, and dramatic changes in leaf shape and complexity. However, aqcfl1 plants have normal flowers and fruits. Our results show that, in contrast to characterized AP1/FUL genes, the AqcFL1 loci are either genetically redundant or have been decoupled from the floral genetic program, and play a major role in leaf morphogenesis. We analyze the results in the context of the core eudicot duplication, and discuss the implications of our findings in terms of the genetic regulation of leaf morphogenesis in Aquilegia and other flowering plants.
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Wang J, Zhang X, Yan G, Zhou Y, Zhang K. Over-expression of the PaAP1 gene from sweet cherry (Prunus avium L.) causes early flowering in Arabidopsis thaliana. JOURNAL OF PLANT PHYSIOLOGY 2013. [PMID: 23206932 DOI: 10.1016/j.jplph.2012.09.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A homologue of SQUAMOSA/APETALA1, designated PaAP1, was isolated from Prunus avium by reverse transcription-PCR (RT-PCR). The full length of PaAP1 cDNA is 753 bp, and it codes for a polypeptide of 250 amino acid residues. Sequence comparison revealed that PaAP1 belongs to the MADS-box gene family. Phylogenetic analysis indicated that PaAP1 shared the highest identity with SQUA/AP1 homologues from Prunus serrulata. Real-time fluorescence quantitative PCR analysis showed that PaAP1 was expressed at high levels in petal, sepal, style, and flower buds, which was slightly different from the expression pattern of AP1 of Arabidopsis thaliana. To characterize the functions of PaAP1, we assessed Arabidopsis transformed with 35S::PaAP1. A total of 8 transgenic T(1) lines with an early flowering phenotype were obtained, and a 3:1 segregation ratio of flowering time was observed in the T(2) generation of 4 lines. This study provides the first functional analysis of an SQUA/AP1 homolog from P. avium and suggests that PaAP1 is potentially useful for shortening the juvenile period in sweet cherry.
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Affiliation(s)
- Jing Wang
- Institute of Forestry and Pomology, Beijing Academy of Agriculture and Forestry Sciences, China
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Heijmans K, Morel P, Vandenbussche M. MADS-box genes and floral development: the dark side. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:5397-404. [PMID: 22915743 DOI: 10.1093/jxb/ers233] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The origin of the flower during evolution has been a crucial step in further facilitating plants to colonize a wide range of different niches on our planet. The >250 000 species of flowering plants existing today display an astonishing diversity in floral architecture. For this reason, the flower is a very attractive subject for evolutionary developmental (evo-devo) genetics studies. Research during the last two decades has provided compelling evidence that the origin and functional diversification of MIKC(c) MADS-box transcription factors has played a critical role during evolution of flowering plants. As master regulators of floral organ identity, MADS-box proteins are at the heart of the classic ABC model for floral development. Despite the enormous progress made in the field of floral development, there still remain aspects that are less well understood. Here we highlight some of the dark corners within our current knowledge on MADS-box genes and flower development, which would be worthwhile investigating in more detail in future research. These include the general question of to what extent MADS-box gene functions are conserved between species, the function of TM8-clade MADS-box genes which so far have remained uncharacterized, the divergence within the A-function, and post-transcriptional regulation of the ABC-genes.
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Affiliation(s)
- Klaas Heijmans
- Plant Genetics, IWWR, Radboud University Nijmegen 6525AJ Nijmegen The Netherlands
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Aceto S, Gaudio L. The MADS and the Beauty: Genes Involved in the Development of Orchid Flowers. Curr Genomics 2012; 12:342-56. [PMID: 22294877 PMCID: PMC3145264 DOI: 10.2174/138920211796429754] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 06/16/2011] [Accepted: 06/21/2011] [Indexed: 11/22/2022] Open
Abstract
Since the time of Darwin, biologists have studied the origin and evolution of the Orchidaceae, one of the largest families of flowering plants. In the last two decades, the extreme diversity and specialization of floral morphology and the uncoupled rate of morphological and molecular evolution that have been observed in some orchid species have spurred interest in the study of the genes involved in flower development in this plant family. As part of the complex network of regulatory genes driving the formation of flower organs, the MADS-box represents the most studied gene family, both from functional and evolutionary perspectives. Despite the absence of a published genome for orchids, comparative genetic analyses are clarifying the functional role and the evolutionary pattern of the MADS-box genes in orchids. Various evolutionary forces act on the MADS-box genes in orchids, such as diffuse purifying selection and the relaxation of selective constraints, which sometimes reveals a heterogeneous selective pattern of the coding and non-coding regions. The emerging theory regarding the evolution of floral diversity in orchids proposes that the diversification of the orchid perianth was a consequence of duplication events and changes in the regulatory regions of the MADS-box genes, followed by sub- and neo-functionalization. This specific developmental-genetic code is termed the "orchid code."
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Affiliation(s)
- Serena Aceto
- Department of Biological Sciences, University of Naples Federico II, Via Mezzocannone 8, 80134 Napoli, Italy
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Berbel A, Ferrándiz C, Hecht V, Dalmais M, Lund OS, Sussmilch FC, Taylor SA, Bendahmane A, Ellis THN, Beltrán JP, Weller JL, Madueño F. VEGETATIVE1 is essential for development of the compound inflorescence in pea. Nat Commun 2012; 3:797. [PMID: 22531182 DOI: 10.1038/ncomms1801] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 03/22/2012] [Indexed: 11/09/2022] Open
Abstract
Unravelling the basis of variation in inflorescence architecture is important to understanding how the huge diversity in plant form has been generated. Inflorescences are divided between simple, as in Arabidopsis, with flowers directly formed at the main primary inflorescence axis, and compound, as in legumes, where they are formed at secondary or even higher order axes. The formation of secondary inflorescences predicts a novel genetic function in the development of the compound inflorescences. Here we show that in pea this function is controlled by VEGETATIVE1 (VEG1), whose mutation replaces secondary inflorescences by vegetative branches. We identify VEG1 as an AGL79-like MADS-box gene that specifies secondary inflorescence meristem identity. VEG1 misexpression in meristem identity mutants causes ectopic secondary inflorescence formation, suggesting a model for compound inflorescence development based on antagonistic interactions between VEG1 and genes conferring primary inflorescence and floral identity. Our study defines a novel mechanism to generate inflorescence complexity.
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Affiliation(s)
- Ana Berbel
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia 46022, Spain
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Pabón-Mora N, Ambrose BA, Litt A. Poppy APETALA1/FRUITFULL orthologs control flowering time, branching, perianth identity, and fruit development. PLANT PHYSIOLOGY 2012; 158:1685-704. [PMID: 22286183 PMCID: PMC3320178 DOI: 10.1104/pp.111.192104] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 01/23/2012] [Indexed: 05/03/2023]
Abstract
Several MADS box gene lineages involved in flower development have undergone duplications that correlate with the diversification of large groups of flowering plants. In the APETALA1 gene lineage, a major duplication coincides with the origin of the core eudicots, resulting in the euFUL and the euAP1 clades. Arabidopsis FRUITFULL (FUL) and APETALA1 (AP1) function redundantly in specifying floral meristem identity but function independently in sepal and petal identity (AP1) and in proper fruit development and determinacy (FUL). Many of these functions are largely conserved in other core eudicot euAP1 and euFUL genes, but notably, the role of APETALA1 as an "A-function" (sepal and petal identity) gene is thought to be Brassicaceae specific. Understanding how functional divergence of the core eudicot duplicates occurred requires a careful examination of the function of preduplication (FUL-like) genes. Using virus-induced gene silencing, we show that FUL-like genes in opium poppy (Papaver somniferum) and California poppy (Eschscholzia californica) function in axillary meristem growth and in floral meristem and sepal identity and that they also play a key role in fruit development. Interestingly, in opium poppy, these genes also control flowering time and petal identity, suggesting that AP1/FUL homologs might have been independently recruited in petal identity. Because the FUL-like gene functional repertoire encompasses all roles previously described for the core eudicot euAP1 and euFUL genes, we postulate subfunctionalization as the functional outcome after the major AP1/FUL gene lineage duplication event.
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Affiliation(s)
| | | | - Amy Litt
- The New York Botanical Garden, Bronx, New York 10458 (N.P.-M., B.A.A., A.L.); and Graduate Center, City University of New York, New York, New York 10016 (N.P.-M.)
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Chi Y, Huang F, Liu H, Yang S, Yu D. An APETALA1-like gene of soybean regulates flowering time and specifies floral organs. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:2251-9. [PMID: 21963279 DOI: 10.1016/j.jplph.2011.08.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 08/04/2011] [Accepted: 08/05/2011] [Indexed: 05/22/2023]
Abstract
MADS-box proteins are key transcription factors involved in plant reproductive development. APETALA1 (AP1) in Arabidopsis is a MIKC-type MADS-box gene and plays important roles in flower development. In this research, we isolated and characterized GmAP1, which encoded an AP1-like protein in soybean. GmAP1 contained eight exons and seven introns and was specifically expressed in the flower, especially in the sepal and petal. GmAP1 was a nucleus-localized transcription factor and displayed transactivation activity. It caused early flowering and alteration of floral organs when ectopically expressed in tobacco. To our knowledge, this is the first report characterizing an AP1-like gene from soybean.
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Affiliation(s)
- Yingjun Chi
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, National Center for Soybean Improvement, Nanjing Agricultural University, Weigang No. 1, Nanjing 210095, China
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Goloveshkina EN, Shul'ga OA, Shchennikova AV, Kamionskaya AM, Skryabin KG. Constitutive expression of the sunflower and chrysanthemum genes of the AP1/FUL group changes flowering timing in transgenic tobacco plants. DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2010; 434:322-4. [PMID: 20963654 DOI: 10.1134/s001249661005008x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Indexed: 11/22/2022]
Affiliation(s)
- E N Goloveshkina
- Bioengineering Center, Russian Academy of Sciences, Moscow, Russia
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Ruokolainen S, Ng YP, Broholm SK, Albert VA, Elomaa P, Teeri TH. Characterization of SQUAMOSA-like genes in Gerbera hybrida, including one involved in reproductive transition. BMC PLANT BIOLOGY 2010; 10:128. [PMID: 20579337 PMCID: PMC3017819 DOI: 10.1186/1471-2229-10-128] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Accepted: 06/25/2010] [Indexed: 05/19/2023]
Abstract
BACKGROUND The flowering process in plants proceeds through the induction of an inflorescence meristem triggered by several pathways. Many of the genes associated with both the flowering process and floral architecture encode transcription factors of the MADS domain family. Gerbera, a member of the sunflower family, Asteraceae, bears compressed inflorescence heads (capitula) with three different flower types characterized by differences in both sexuality and floral symmetry. To understand how such a complex inflorescence structure is achieved at the molecular level, we have characterized the array of Gerbera MADS box genes. The high number of SQUAMOSA-like genes in Gerbera compared to other model species raised the question as to whether they may relate to Gerbera's complex inflorescence structure and whether or not a homeotic A function is present. RESULTS In this paper we describe six Gerbera genes related to the SQUAMOSA/APETALA1/FRUITFULL genes of snapdragon and Arabidopsis. Based on phylogenetic analysis of the entire gene lineage, our data indicates that GSQUA1 and GSQUA3 are members of the SQUA/AP1 clade, while GSQUA2, GSQUA4, GSQUA5 and GSQUA6 are co-orthologs of the Arabidopsis FUL gene. GSQUA1/GSQUA3 and GSQUA4/GSQUA5/GSQUA6, respectively, represent several gene duplication events unknown in the model systems that may be specific to either Gerbera or Asteraceae. GSQUA genes showed specific expression profiles. GSQUA1, GSQUA2, and GSQUA5 were inflorescence abundant, while GSQUA3, GSQUA4, and GSQUA6 expression was also detected in vegetative organs. Overexpression of GSQUA2 in Gerbera led to accelerated flowering, dwarfism and vegetative abnormalities, all new and specific phenomena observed in transgenic Gerbera plants with modified MADS box gene expression. CONCLUSIONS Based on expression patterns, none of the Gerbera SQUA-like genes are likely to control flower organ identity in the sense of the floral A function. However, our data shows that the FUL-like gene GSQUA2 plays a vital role in meristem transition. The roles of other GSQUA-genes in Gerbera floral development are intriguing, but require still further study.
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Affiliation(s)
- Satu Ruokolainen
- Gerbera Laboratory, Department of Agricultural Sciences, P.O. Box 27 (Latokartanonkaari 7), FIN - 00014 University of Helsinki, Finland
| | - Yan Peng Ng
- Biomedicum Helsinki, P.O. Box 63 (Haartmaninkatu 8), FIN-00014 University of Helsinki, Finland
| | - Suvi K Broholm
- Gerbera Laboratory, Department of Agricultural Sciences, P.O. Box 27 (Latokartanonkaari 7), FIN - 00014 University of Helsinki, Finland
| | - Victor A Albert
- Department of Biological Sciences, University at Buffalo (SUNY), Buffalo, NY, 14260, USA
| | - Paula Elomaa
- Gerbera Laboratory, Department of Agricultural Sciences, P.O. Box 27 (Latokartanonkaari 7), FIN - 00014 University of Helsinki, Finland
| | - Teemu H Teeri
- Gerbera Laboratory, Department of Agricultural Sciences, P.O. Box 27 (Latokartanonkaari 7), FIN - 00014 University of Helsinki, Finland
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Litt A, Kramer EM. The ABC model and the diversification of floral organ identity. Semin Cell Dev Biol 2009; 21:129-37. [PMID: 19948236 DOI: 10.1016/j.semcdb.2009.11.019] [Citation(s) in RCA: 122] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 11/16/2009] [Accepted: 11/23/2009] [Indexed: 01/22/2023]
Abstract
Broad studies of the ABC program across angiosperms have found that interactions between gene duplication, biochemical evolution, shifts in gene expression and modification of existing identity programs have been critical to the evolution of floral morphology. Several themes can be recognized in this context. First, the original concept of "A" function applies only very narrowly to Arabidopsis and its close relatives. Second, while many types of petaloid organs are associated with the expression of AP3/PI homologs, there is growing evidence that there are other genetic mechanisms for producing petaloidy, especially in first whorl organs. Third, pre-existing organ identity programs can be modified to yield novel organ types, often in association with gene duplications. Lastly, there are many aspects of ABC gene function outside the major model systems that remain a mystery, perhaps none more so than the C-terminal amino acid motifs that distinguish specific ABC gene lineages.
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Affiliation(s)
- Amy Litt
- The New York Botanical Garden, Bronx, NY 10458, USA.
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Lin EP, Peng HZ, Jin QY, Deng MJ, Li T, Xiao XC, Hua XQ, Wang KH, Bian HW, Han N, Zhu MY. Identification and characterization of two bamboo (Phyllostachys praecox) AP1/SQUA-like MADS-box genes during floral transition. PLANTA 2009; 231:109-20. [PMID: 19855996 DOI: 10.1007/s00425-009-1033-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2009] [Accepted: 09/24/2009] [Indexed: 05/20/2023]
Abstract
Bamboo (Bambusoideae) is by far the largest member of the grass family Poaceae, which is vital to the economy of many countries in the tropics and subtropics. However, the mechanism of flowering of bamboo (Phyllostachys praecox) is still unknown. In this study, we isolated two novel genes from P. praecox and evaluated their functional characteristics. The sequence and phylogenetic analysis indicated that these two genes, named PpMADS1 and PpMADS2, belong to FUL3 and FUL1 clade of Poaceae AP1/SQUA-like genes, respectively. The PpMADS2 possesses a truncated C terminus lacking the highly conserved paleoAP1 motif. It was further confirmed that the truncated C-terminal region was produced by natural sequence deletion in exons, but not by alternative splicing. Ectopic expression of PpMADS1 and PpMADS2 significantly promoted early flowering through upregulation of AP1 in Arabidopsis. Yeast two-hybrid experiments demonstrated that AP1 protein can interact with PpMADS1 but not PpMADS2, suggesting that these two genes may act differently in signaling early flowering of bamboo plants. RT-qPCR and in situ hybridization analysis revealed distinct expression patterns of these two genes in vegetative and reproductive tissues of bamboo. Taken together, our results suggest that both PpMADS1 and PpMADS2 are involved in floral transition, and PpMADS2 might play more important roles than PpMADS1 in floral development of Phyllostachys praecox.
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Affiliation(s)
- Er-Pei Lin
- State Key Laboratory of Plant Physiology and Biochemistry, Key Laboratory for Cell and Gene Engineering of Zhejiang Province, College of Life Sciences, Zhejiang University, 310058, Hangzhou, Zhejiang, China
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Libault M, Joshi T, Benedito VA, Xu D, Udvardi MK, Stacey G. Legume transcription factor genes: what makes legumes so special? PLANT PHYSIOLOGY 2009; 151:991-1001. [PMID: 19726573 PMCID: PMC2773095 DOI: 10.1104/pp.109.144105] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Accepted: 08/26/2009] [Indexed: 05/18/2023]
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Benlloch R, Roque E, Ferrándiz C, Cosson V, Caballero T, Penmetsa RV, Beltrán JP, Cañas LA, Ratet P, Madueño F. Analysis of B function in legumes: PISTILLATA proteins do not require the PI motif for floral organ development in Medicago truncatula. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 60:102-11. [PMID: 19500303 DOI: 10.1111/j.1365-313x.2009.03939.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The B-class gene PISTILLATA (PI) codes for a MADS-box transcription factor required for floral organ identity in angiosperms. Unlike Arabidopsis, it has been suggested that legume PI genes contribute to a variety of processes, such as the development of floral organs, floral common petal-stamen primordia, complex leaves and N-fixing root nodules. Another interesting feature of legume PI homologues is that some of them lack the highly conserved C-terminal PI motif suggested to be crucial for function. Therefore, legume PI genes are useful for addressing controversial questions on the evolution of B-class gene function, including how they may have diverged in both function and structure to affect different developmental processes. However, functional analysis of legume PI genes has been hampered because no mutation in any B-class gene has been identified in legumes. Here we fill this gap by studying the PI function in the model legume species Medicago truncatula using mutant and RNAi approaches. Like other legume species, M. truncatula has two PI homologues. The expression of the two genes, MtPI and MtNGL9, has strongly diverged, suggesting differences in function. Our analyses show that these genes are required for petal and stamen identity, where MtPI appears to play a predominant role. However, they appear not to be required for development of the nodule, the common primordia or the complex leaf. Moreover, both M. truncatula PI homologues lack the PI motif, which indicates that the C-terminal motif is not essential for PI activity.
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Affiliation(s)
- Reyes Benlloch
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), UPV-CSIC., 46022 Valencia, Spain
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Weller JL, Hecht V, Liew LC, Sussmilch FC, Wenden B, Knowles CL, Vander Schoor JK. Update on the genetic control of flowering in garden pea. JOURNAL OF EXPERIMENTAL BOTANY 2009; 60:2493-9. [PMID: 19414500 DOI: 10.1093/jxb/erp120] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The garden pea has been a model for the genetics of flowering for several decades and numerous flowering loci have been identified, but until recently little was known about the molecular nature of these loci. This paper presents an update on recent work on the molecular genetics of flowering in pea, outlining progress in gene and mutant isolation, expression analyses, grafting and other physiological studies, and candidate gene assessment. Work so far has led to the identification of the LATE1 and DNE loci as orthologues of Arabidopsis GIGANTEA and ELF4, respectively, and candidate genes for several other loci are being evaluated. Expression analysis of an expanded FT-like gene family suggests a more complex role for this group of genes. These results provide the first insight into the circadian clock, photoperiod response mechanism, and mobile signals in pea, and identify both conserved and divergent features in comparison with Arabidopsis.
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Affiliation(s)
- James L Weller
- School of Plant Science, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia.
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Sather DN, Golenberg EM. Duplication of AP1 within the Spinacia oleracea L. AP1/FUL clade is followed by rapid amino acid and regulatory evolution. PLANTA 2009; 229:507-521. [PMID: 19005675 DOI: 10.1007/s00425-008-0851-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 10/22/2008] [Indexed: 05/27/2023]
Abstract
The AP1/FUL clade of MADS box genes have undergone multiple duplication events among angiosperm species. While initially identified as having floral meristem identity and floral organ identity function in Arabidopsis, the role of AP1 homologs does not appear to be universally conserved even among eudicots. In comparison, the role of FRUITFULL has not been extensively explored in non-model species. We report on the isolation of three AP1/FUL genes from cultivated spinach, Spinacia oleracea L. Two genes, designated SpAPETALA1-1 (SpAP1-1) and SpAPETALA1-2 (SpAP1-2), cluster as paralogous genes within the Caryophyllales AP1 clade. They are highly differentiated in the 3', carboxyl-end encoding region of the gene following the third amphipathic alpha-helix region, while still retaining some elements of a signature AP1 carboxyl motifs. In situ hybridization studies also demonstrate that the two paralogs have evolved different temporal and spatial expression patterns, and that neither gene is expressed in the developing sepal whorl, suggesting that the AP1 floral organ identity function is not conserved in spinach. The spinach FRUITFULL homolog, SpFRUITFULL (SpFUL), has retained the conserved motif and groups with Caryophyllales FRUITFULL homologs. SpFUL is expressed in leaf as well as in floral tissue, and shows strong expression late in flower development, particularly in the tapetal layer in males, and in the endothecium layer and stigma, in the females. The combined evidence of high rates of non-synonymous substitutions and differential expression patterns supports a scenario in which the AP1 homologs in the spinach AP1/FUL gene family have experienced rapid evolution following duplication.
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Affiliation(s)
- D Noah Sather
- Department of Biological Sciences, Wayne State University, Detroit, MI, 48202, USA.
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Abstract
Petals appear in many angiosperm taxa, yet when and how these attractive organs originated remains unclear. Phylogenetic reconstructions based on morphological data suggest that petals have evolved multiple times during the radiation of the angiosperms. Based on the diversity of petal morphologies, it is likely that the developmental programmes specifying petal identity are distinct in different lineages. On the other hand, molecular genetic analyses have suggested that the specification of petal identity in different lineages utilizes similar genetic pathways. Together, these observations indicate that the evolution of petals has relied on the repeated recruitment of a suite of interacting developmental control genes, albeit in different ways in different lineages. These observations suggest that this gene regulatory network represents a 'deep homology' in plant evolution. A major challenge is to understand how this ancestral developmental pathway has been redeployed in different angiosperm lineages, and how changes in the workings of this pathway have led to the myriad shapes, colours, and sizes of petals.
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Affiliation(s)
- Vivian F Irish
- Department of Molecular, Cellular and Developmental Biology, Yale University, 266 Whitney Ave., New Haven, CT 06520-8104, USA.
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Su K, Zhao S, Shan H, Kong H, Lu W, Theissen G, Chen Z, Meng Z. The MIK region rather than the C-terminal domain of AP3-like class B floral homeotic proteins determines functional specificity in the development and evolution of petals. THE NEW PHYTOLOGIST 2008; 178:544-558. [PMID: 18298432 DOI: 10.1111/j.1469-8137.2008.02382.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
In core eudicots, euAP3-type MADS-box genes encode a PISTILLATA (PI)-derived motif, as well as a C-terminal euAP3 motif that originated from a paleoAP3 motif of an ancestral APETALA3 (AP3)-like protein through a translational frameshift mutation. To determine the functional and evolutionary relevance of these motifs, a series of point mutation and domain-swap constructs were generated, involving CsAP3, a paleoAP3-type gene from the basal angiosperm Chloranthus spicatus encoding a truncated paleoAP3 motif, and AtAP3, a euAP3-type gene from the core eudicot Arabidopsis thaliana. The chimeric constructs were expressed in A. thaliana under the control of the AP3 promoter or the CaMV 35S promoter in an ap3 mutant or wild-type background, respectively. Significant recovery of AP3 function was obtained in both complementation and ectopic expression experiments whenever the region upstream of the C-terminal motifs (MIK region) from A. thaliana was taken, even when the PI-derived motif and the truncated paleoAP3 motif of CsAP3 substituted for the corresponding sequences from AtAP3. However, no or very weak complementation or gain-of-function was seen when the MIK region was from CsAP3. Our data suggest that changes in the MIK region rather than mutations in the C-terminal domain were of crucial importance for the evolution of the functional specificity of euAP3-type proteins in stamen and petal development.
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Affiliation(s)
- Kunmei Su
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Xiangshan, Beijing, 100093, China
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Preston JC, Kellogg EA. Conservation and divergence of APETALA1/FRUITFULL-like gene function in grasses: evidence from gene expression analyses. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2007; 52:69-81. [PMID: 17666026 DOI: 10.1111/j.1365-313x.2007.03209.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Duplicated APETALA1/FRUITFULL (AP1/FUL) genes show distinct but overlapping patterns of expression within rice (Oryza sativa) and within ryegrass (Lolium temulentum), suggesting discrete functional roles in the transition to flowering, specification of spikelet meristem identity, and specification of floral organ identity. In this study, we analyzed the expression of the AP1/FUL paralogues FUL1 and FUL2 across phylogenetically disparate grasses to test hypotheses of gene function. In combination with other studies, our data support similar roles for both genes in spikelet meristem identity, a general role for FUL1 in floral organ identity, and a more specific role for FUL2 in outer floral whorl identity. In contrast to Arabidopsis AP1/FUL genes, expression of FUL1 and FUL2 is consistent with an early role in the transition to flowering. In general, FUL1 has a wider expression pattern in all spikelet organs than FUL2, but both genes are expressed in all spikelet organs in some cereals. FUL1 and FUL2 appear to have multiple redundant functions in early inflorescence development. We hypothesize that sub-functionalization of FUL2 and interaction of FUL2 with LHS1 could specify lemma and palea identity in the grass floret.
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Affiliation(s)
- Jill C Preston
- Department of Biology, University of Missouri - St Louis, One University Boulevard, St Louis, MO 63121, USA.
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Chen D, Guo B, Hexige S, Zhang T, Shen D, Ming F. SQUA-like genes in the orchid Phalaenopsis are expressed in both vegetative and reproductive tissues. PLANTA 2007; 226:369-80. [PMID: 17377807 DOI: 10.1007/s00425-007-0488-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2006] [Accepted: 01/29/2007] [Indexed: 05/05/2023]
Abstract
The SQUA family (AP1/FUL family) of MADS-box genes plays an important role in the transition from the vegetative to the reproductive development of angiosperms, and its origin might be concurrent with fixation of floral structure in angiosperms. Here, we isolated two Phalaenopsis MADS-box genes designated ORAP11 and ORAP13, both of which belong to the monocot FUL-like clade of the SQUA family. RT-PCR showed that both genes are strongly expressed in the floral bud, and also detected in the vegetative organs. During later stages, ORAP11 was only detected in the column, but ORAP13 signal was absent from all of the floral organs. In-situ hybridization experiments detected both genes in the tips and margins of developing petals and lips, the developing column, and ovule. Over-expression of both genes in tobacco induced early flowering and changed plant architecture. Our results suggest that in Phalaenopsis, both genes might share partly redundant activities and play important roles in the process of floral transition and morphological architecture.
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Affiliation(s)
- Donghong Chen
- Institute of Genetics, State Key Laboratory of Genetic Engineering, Research Center of Gene Diversity and Designed Agriculture, School of Life Science, Fudan University, Shanghai 200433, China
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Shan H, Zhang N, Liu C, Xu G, Zhang J, Chen Z, Kong H. Patterns of gene duplication and functional diversification during the evolution of the AP1/SQUA subfamily of plant MADS-box genes. Mol Phylogenet Evol 2007; 44:26-41. [PMID: 17434760 DOI: 10.1016/j.ympev.2007.02.016] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Revised: 02/07/2007] [Accepted: 02/19/2007] [Indexed: 01/30/2023]
Abstract
Members of the AP1/SQUA subfamily of plant MADS-box genes play broad roles in the regulation of reproductive meristems, the specification of sepal and petal identities, and the development of leaves and fruits. It has been shown that AP1/SQUA-like genes are angiosperm-specific, and have experienced several major duplication events. However, the evolutionary history of this subfamily is still uncertain. Here, we report the isolation of 14 new AP1/SQUA-like genes from seven early-diverging eudicots and the identification of 11 previously uncharacterized ESTs and genomic sequences from public databases. Sequence comparisons of these and other published sequences reveal a conserved C-terminal region, the FUL motif, in addition to the known euAP1/paleoAP1 motif, in AP1/SQUA-like proteins. Phylogenetic analyses further suggest that there are three major lineages (euAP1, euFUL, and AGL79) in core eudicots, likely resulting from two close duplication events that predated the divergence of core eudicots. Among the three lineages, euFUL is structurally very similar to FUL-like genes from early-diverging eudicots and basal angiosperms, whereas euAP1 might have originally been generated through a 1-bp deletion in the exon 8 of an ancestral euFUL- or FUL-like gene. Because euFUL- and FUL-like genes usually have broad expression patterns, we speculate that AP1/SQUA-like genes initially had broad functions. Based on these observations, the evolutionary fates of duplicate genes and the contributions of the frameshift mutation and alternative splicing to functional diversity are discussed.
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Affiliation(s)
- Hongyan Shan
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Xiangshan, Beijing, People's Republic of China
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