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Kaur A, Best NB, Hartwig T, Budka J, Khangura RS, McKenzie S, Aragón-Raygoza A, Strable J, Schulz B, Dilkes BP. A maize semi-dwarf mutant reveals a GRAS transcription factor involved in brassinosteroid signaling. PLANT PHYSIOLOGY 2024; 195:3072-3096. [PMID: 38709680 PMCID: PMC11288745 DOI: 10.1093/plphys/kiae147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 01/18/2024] [Accepted: 01/18/2024] [Indexed: 05/08/2024]
Abstract
Brassinosteroids (BR) and gibberellins (GA) regulate plant height and leaf angle in maize (Zea mays). Mutants with defects in BR or GA biosynthesis or signaling identify components of these pathways and enhance our knowledge about plant growth and development. In this study, we characterized three recessive mutant alleles of GRAS transcription factor 42 (gras42) in maize, a GRAS transcription factor gene orthologous to the DWARF AND LOW TILLERING (DLT) gene of rice (Oryza sativa). These maize mutants exhibited semi-dwarf stature, shorter and wider leaves, and more upright leaf angle. Transcriptome analysis revealed a role for GRAS42 as a determinant of BR signaling. Analysis of the expression consequences from loss of GRAS42 in the gras42-mu1021149 mutant indicated a weak loss of BR signaling in the mutant, consistent with its previously demonstrated role in BR signaling in rice. Loss of BR signaling was also evident by the enhancement of weak BR biosynthetic mutant alleles in double mutants of nana plant1-1 and gras42-mu1021149. The gras42-mu1021149 mutant had little effect on GA-regulated gene expression, suggesting that GRAS42 is not a regulator of core GA signaling genes in maize. Single-cell expression data identified gras42 expressed among cells in the G2/M phase of the cell cycle consistent with its previously demonstrated role in cell cycle gene expression in Arabidopsis (Arabidopsis thaliana). Cis-acting natural variation controlling GRAS42 transcript accumulation was identified by expression genome-wide association study (eGWAS) in maize. Our results demonstrate a conserved role for GRAS42/SCARECROW-LIKE 28 (SCL28)/DLT in BR signaling, clarify the role of this gene in GA signaling, and suggest mechanisms of tillering and leaf angle control by BR.
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Affiliation(s)
- Amanpreet Kaur
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Norman B Best
- Plant Genetics Research Unit, USDA-ARS, Columbia, MO 65211, USA
| | - Thomas Hartwig
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Josh Budka
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Rajdeep S Khangura
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Steven McKenzie
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
| | - Alejandro Aragón-Raygoza
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Josh Strable
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA
| | - Burkhard Schulz
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742, USA
| | - Brian P Dilkes
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907USA
- Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA
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Li Q, Liu N, Wu C. Novel insights into maize (Zea mays) development and organogenesis for agricultural optimization. PLANTA 2023; 257:94. [PMID: 37031436 DOI: 10.1007/s00425-023-04126-y] [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: 08/04/2022] [Accepted: 03/22/2023] [Indexed: 06/19/2023]
Abstract
In maize, intrinsic hormone activities and sap fluxes facilitate organogenesis patterning and plant holistic development; these hormone movements should be a primary focus of developmental biology and agricultural optimization strategies. Maize (Zea mays) is an important crop plant with distinctive life history characteristics and structural features. Genetic studies have extended our knowledge of maize developmental processes, genetics, and molecular ecophysiology. In this review, the classical life cycle and life history strategies of maize are analyzed to identify spatiotemporal organogenesis properties and develop a definitive understanding of maize development. The actions of genes and hormones involved in maize organogenesis and sex determination, along with potential molecular mechanisms, are investigated, with findings suggesting central roles of auxin and cytokinins in regulating maize holistic development. Furthermore, investigation of morphological and structural characteristics of maize, particularly node ubiquity and the alternate attachment pattern of lateral organs, yields a novel regulatory model suggesting that maize organ initiation and subsequent development are derived from the stimulation and interaction of auxin and cytokinin fluxes. Propositions that hormone activities and sap flow pathways control organogenesis are thoroughly explored, and initiation and development processes of distinctive maize organs are discussed. Analysis of physiological factors driving hormone and sap movement implicates cues of whole-plant activity for hormone and sap fluxes to stimulate maize inflorescence initiation and organ identity determination. The physiological origins and biogenetic mechanisms underlying maize floral sex determination occurring at the tassel and ear spikelet are thoroughly investigated. The comprehensive outline of maize development and morphogenetic physiology developed in this review will enable farmers to optimize field management and will provide a reference for de novo crop domestication and germplasm improvement using genome editing biotechnologies, promoting agricultural optimization.
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Affiliation(s)
- Qinglin Li
- Crop Genesis and Novel Agronomy Center, Yangling, 712100, Shaanxi, China.
| | - Ning Liu
- Shandong ZhongnongTiantai Seed Co., Ltd, Pingyi, 273300, Shandong, China
| | - Chenglai Wu
- State Key Laboratory of Crop Biology, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
- College of Agronomy, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
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Genome-Wide Identification of Wheat KNOX Gene Family and Functional Characterization of TaKNOX14-D in Plants. Int J Mol Sci 2022; 23:ijms232415918. [PMID: 36555558 PMCID: PMC9784718 DOI: 10.3390/ijms232415918] [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: 11/12/2022] [Revised: 12/05/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
The KNOX genes play important roles in maintaining SAM and regulating the development of plant leaves. However, the TaKNOX genes in wheat are still not well understood, especially their role in abiotic stress. In this study, a total of 36 KNOX genes were identified, and we demonstrated the function of the TaKNOX14-D gene under mechanical injury and cold stress. Thirty-six TaKNOX genes were divided into two groups, and thirty-four TaKNOX genes were predicted to be located in the nucleus by Cell-PLoc. These genes contained five tandem duplications. Fifteen collinear gene pairs were exhibited in wheat and rice, one collinear gene pair was exhibited in wheat and Arabidopsis. The phylogenetic tree and motif analysis suggested that the TaKNOX gene appeared before C3 and C4 diverged. Gene structure showed that the numbers of exons and introns in TaKNOX gene are different. Wheat TaKNOX genes showed different expression patterns during the wheat growth phase, with seven TaKNOX genes being highly expressed in the whole growth period. These seven genes were also highly expressed in most tissues, and also responded to most abiotic stress. Eleven TaKNOX genes were up-regulated in the tillering node during the leaf regeneration period after mechanical damage. When treating the wheat with different hormones, the expression patterns of TaKNOX were changed, and results showed that ABA promoted TaKNOX expression and seven TaKNOX genes were up-regulated under cytokinin and auxin treatment. Overexpression of the TaKNOX14-D gene in Arabidopsis could increase the leaf size, plant height and seed size. This gene overexpression in Arabidopsis also increased the compensatory growth capacity after mechanical damage. Overexpression lines also showed high resistance to cold stress. This study provides a better understanding of the TaKNOX genes.
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Fang SC, Chen JC, Chang PY, Lin HY. Co-option of the SHOOT MERISTEMLESS network regulates protocorm-like body development in Phalaenopsis aphrodite. PLANT PHYSIOLOGY 2022; 190:127-145. [PMID: 35258627 PMCID: PMC9434259 DOI: 10.1093/plphys/kiac100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 01/08/2022] [Indexed: 06/02/2023]
Abstract
The protocorm is a structure that is formed upon germination of an orchid seed. It lacks cotyledons and is ovoid in shape. The protocorm-like body (PLB), on the other hand, is a protocorm-like organ induced from somatic tissues. PLBs have been widely used for orchid micropropagation. Because of its unique structure and its application in the orchid industry, PLB development has drawn considerable interest from orchid and developmental biologists. Our previous genome-wide comparative transcriptome study demonstrated that protocorms and PLBs share similar molecular signatures and suggested that SHOOT MERISTEMLESS (STM)-dependent organogenesis is important for PLB development. Here, we show that overexpression of Phalaenopsis aphrodite STM (PaSTM) greatly enhances PLB regeneration from vegetative tissue-based explants of Phalaenopsis orchids, confirming its regulatory role in PLB development. Expression of PaSTM restored shoot meristem function of the Arabidopsis (Arabidopsis thaliana) stm-2 mutant. Moreover, we identified class S11 MYB transcription factors (TFs) as targets downstream of PaSTM. A cis-acting element, TTGACT, identified in the promoters of S11 MYB TFs was found to be important for PaSTM binding and activation. Overexpression of PaSTM or its downstream targets, PaMYB13, PaMYB14, and PaMYB17, enhanced de novo shoot regeneration in Arabidopsis, indicating the active role of the PaSTM-S11 PaMYB module in organogenesis. In summary, our data demonstrate that PaSTM is important for PLB development. The STM-S11 MYB regulatory module is evolutionarily conserved and may regulate shoot or shoot-related organ development in plants.
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Affiliation(s)
| | - Jhun-Chen Chen
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 741, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Pou-Yi Chang
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 741, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Hsiang-Yin Lin
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 741, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
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Kitagawa M, Xu X, Jackson D. Trafficking and localization of KNOTTED1 related mRNAs in shoot meristems. Commun Integr Biol 2022; 15:158-163. [PMID: 35832536 PMCID: PMC9272838 DOI: 10.1080/19420889.2022.2095125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Multicellular organisms use transcripts and proteins as signaling molecules for cell-to-cell communication. Maize KNOTTED1 (KN1) was the first homeodomain transcription factor identified in plants, and functions in maintaining shoot stem cells. KN1 acts non-cell autonomously, and both its messenger RNA (mRNA) and protein traffic between cells through intercellular nanochannels called plasmodesmata. KN1 protein and mRNA trafficking are regulated by a chaperonin subunit and a catalytic subunit of the RNA exosome, respectively. These studies suggest that the function of KN1 in stem cell regulation requires the cell-to-cell transport of both its protein and mRNA. However, in situ hybridization experiments published 25 years ago suggested that KN1 mRNA was missing from the epidermal (L1) layer of shoot meristems, suggesting that only the KN1 protein could traffic. Here, we show evidence that KN1 mRNA is present at a low level in L1 cells of maize meristems, supporting an idea that both KN1 protein and mRNA traffic to the L1 layer. We also summarize mRNA expression patterns of KN1 homologs in diverse angiosperm species, and discuss KN1 trafficking mechanisms.
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Affiliation(s)
| | - Xiaosa Xu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - David Jackson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
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6
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Richardson AE, Hake S. The power of classic maize mutants: Driving forward our fundamental understanding of plants. THE PLANT CELL 2022; 34:2505-2517. [PMID: 35274692 PMCID: PMC9252469 DOI: 10.1093/plcell/koac081] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 02/08/2022] [Indexed: 05/12/2023]
Abstract
Since Mendel, maize has been a powerhouse of fundamental genetics research. From testing the Mendelian laws of inheritance, to the first genetic and cytogenetic maps, to the use of whole-genome sequencing data for crop improvement, maize is at the forefront of genetics advances. Underpinning much of this revolutionary work are the classic morphological mutants; the "freaks" that stood out in the field to even the untrained eye. Here we review some of these classic developmental mutants and their importance in the history of genetics, as well as their key role in our fundamental understanding of plant development.
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Affiliation(s)
- Annis E Richardson
- School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
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Han Y, Zhang L, Yan L, Xiong X, Wang W, Zhang XH, Min DH. Genome-wide analysis of TALE superfamily in Triticum aestivum reveals TaKNOX11-A is involved in abiotic stress response. BMC Genomics 2022; 23:89. [PMID: 35100988 PMCID: PMC8805372 DOI: 10.1186/s12864-022-08324-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 01/17/2022] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Three-amino-loop-extension (TALE) superfamily genes are widely present in plants and function directly in plant growth and development and abiotic stress response. Although TALE genes have been studied in many plant species, members of the TALE family have not been identified in wheat. RESULTS In this study, we identified 70 wheat TALE protein candidate genes divided into two subfamilies, KNOX (KNOTTED-like homeodomain) and BEL1-like (BLH/BELL homeodomain). Genes in the same subfamily or branch in the phylogenetic tree are similar in structure, and their encoded proteins have similar motifs and conserved structures. Wheat TALE genes are unevenly distributed on 21 chromosomes and expanded on the fourth chromosome. Through gene duplication analysis, 53 pairs of wheat TALE genes were determined to result from segmental duplication events, and five pairs were caused by tandem duplication events. The Ka/Ks between TALE gene pairs indicates a strong purification and selection effect. There are multiple cis-elements in the 2000 bp promoter sequence that respond to hormones and abiotic stress, indicating that most wheat TALE genes are involved in the growth, development, and stress response of wheat. We also studied the expression profiles of wheat TALE genes in different developmental stages and tissues and under different stress treatments. We detected the expression levels of four TALE genes by qRT-PCR, and selected TaKNOX11-A for further downstream analysis. TaKNOX11-A enhanced the drought and salt tolerances of Arabidopsis thaliana. TaKNOX11-A overexpressing plants had decreased malondialdehyde content and increased proline content, allowing for more effective adaptation of plants to unfavorable environments. CONCLUSIONS We identified TALE superfamily members in wheat and conducted a comprehensive bioinformatics analysis. The discovery of the potential role of TaKNOX11-A in drought resistance and salt tolerance provides a basis for follow-up studies of wheat TALE family members, and also provides new genetic resources for improving the stress resistance of wheat.
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Affiliation(s)
- Yuxuan Han
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Lili Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Luyu Yan
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China
| | - Xinxin Xiong
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China
| | - Wenjing Wang
- Shaanxi Agricultural Machinery Appraisal and Extension Station, Xian, Shaanxi, China
| | - Xiao-Hong Zhang
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China.
| | - Dong-Hong Min
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China.
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8
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Strable J, Nelissen H. The dynamics of maize leaf development: Patterned to grow while growing a pattern. CURRENT OPINION IN PLANT BIOLOGY 2021; 63:102038. [PMID: 33940553 DOI: 10.1016/j.pbi.2021.102038] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/03/2021] [Accepted: 03/04/2021] [Indexed: 05/12/2023]
Abstract
Leaves are a significant component of the shoot system in grasses, functioning in light capture and photosynthesis. Leaf width, length, and angle are expressions of development that collectively define canopy architecture. Thus, the distinctive morphology of grass leaves is an interdependent readout of developmental patterning and growth along the proximal-distal, medial-lateral, and adaxial-abaxial axes. Here, we review the chronology of patterning and growth, namely along the proximal-distal axis, during maize leaf development. We underscore that patterning and growth occur simultaneously, making use of shared developmental gradients and molecular pathways.
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Affiliation(s)
- Josh Strable
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA 27695.
| | - Hilde Nelissen
- Ghent University, Department of Plant Biotechnology and Bioinformatics, 9052, Ghent, Belgium; VIB Center for Plant Systems Biology, 9052, Ghent, Belgium.
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Strable J. Developmental genetics of maize vegetative shoot architecture. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2021; 41:19. [PMID: 37309417 PMCID: PMC10236122 DOI: 10.1007/s11032-021-01208-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/25/2021] [Indexed: 06/13/2023]
Abstract
More than 1.1 billion tonnes of maize grain were harvested across 197 million hectares in 2019 (FAOSTAT 2020). The vast global productivity of maize is largely driven by denser planting practices, higher yield potential per area of land, and increased yield potential per plant. Shoot architecture, the three-dimensional structural arrangement of the above-ground plant body, is critical to maize grain yield and biomass. Structure of the shoot is integral to all aspects of modern agronomic practices. Here, the developmental genetics of the maize vegetative shoot is reviewed. Plant architecture is ultimately determined by meristem activity, developmental patterning, and growth. The following topics are discussed: shoot apical meristem, leaf architecture, axillary meristem and shoot branching, and intercalary meristem and stem activity. Where possible, classical and current studies in maize developmental genetics, as well as recent advances leveraged by "-omics" analyses, are highlighted within these sections. Supplementary Information The online version contains supplementary material available at 10.1007/s11032-021-01208-1.
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Affiliation(s)
- Josh Strable
- Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853 USA
- Present Address: Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695 USA
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Chen Z, Gallavotti A. Improving architectural traits of maize inflorescences. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2021; 41:21. [PMID: 37309422 PMCID: PMC10236070 DOI: 10.1007/s11032-021-01212-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 02/02/2021] [Indexed: 06/13/2023]
Abstract
The domestication and improvement of maize resulted in radical changes in shoot architecture relative to its wild progenitor teosinte. In particular, critical modifications involved a reduction of branching and an increase in inflorescence size to meet the needs for human consumption and modern agricultural practices. Maize is a major contributor to global agricultural production by providing large and inexpensive quantities of food, animal feed, and ethanol. Maize is also a classic system for studying the genetic regulation of inflorescence formation and its enlarged female inflorescences directly influence seed production and yield. Studies on the molecular and genetic networks regulating meristem proliferation and maintenance, including receptor-ligand interactions, transcription factor regulation, and hormonal control, provide important insights into maize inflorescence development and reveal potential avenues for the targeted modification of specific architectural traits. In this review, we summarize recent findings on the molecular mechanisms controlling inflorescence formation and discuss how this knowledge can be applied to improve maize productivity in the face of present and future environmental challenges.
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Affiliation(s)
- Zongliang Chen
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ 08854-8020 USA
| | - Andrea Gallavotti
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ 08854-8020 USA
- Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901 USA
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Abstract
A fascinating feature of plant growth and development is that plants initiate organs continually throughout their lifespan. The ability to do this relies on specialized groups of pluripotent stem cells termed meristems, which allow for the elaboration of the shoot, root, and vascular systems. We now have a deep understanding of the genetic networks that control meristem initiation and stem cell maintenance, including the roles of receptors and their ligands, transcription factors, and integrated hormonal and chromatin control. This review describes these networks and discusses how this knowledge is being applied to improve crop productivity by increasing fruit size and seed number.
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Affiliation(s)
- Munenori Kitagawa
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA;
| | - David Jackson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA;
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12
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Wu Q, Xu F, Jackson D. All together now, a magical mystery tour of the maize shoot meristem. CURRENT OPINION IN PLANT BIOLOGY 2018; 45:26-35. [PMID: 29778985 DOI: 10.1016/j.pbi.2018.04.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 03/30/2018] [Accepted: 04/15/2018] [Indexed: 05/11/2023]
Abstract
Crop yield improvement requires optimization of shoot architecture, and can be facilitated by understanding shoot apical meristem (SAM) development. Maize, as one of the most important cereal crops worldwide, is also a model system and has significantly contributed to our fundamental understanding of SAM development. In this review, we focus on recent progress and will discuss communication between different meristem regulators, including CLAVATA receptors and ligands, transcription factors, small RNAs and hormones, as well as the importance of communication between different SAM regions.
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Affiliation(s)
- Qingyu Wu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, United States
| | - Fang Xu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, United States
| | - David Jackson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, United States.
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Tsuda K, Abraham-Juarez MJ, Maeno A, Dong Z, Aromdee D, Meeley R, Shiroishi T, Nonomura KI, Hake S. KNOTTED1 Cofactors, BLH12 and BLH14, Regulate Internode Patterning and Vein Anastomosis in Maize. THE PLANT CELL 2017; 29:1105-1118. [PMID: 28381444 PMCID: PMC5466031 DOI: 10.1105/tpc.16.00967] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/03/2017] [Accepted: 03/28/2017] [Indexed: 05/20/2023]
Abstract
Monocot stems lack the vascular cambium and instead have characteristic structures in which intercalary meristems generate internodes and veins remain separate and scattered. However, developmental processes of these unique structures have been poorly described. BELL1-like homeobox (BLH) transcription factors (TFs) are known to heterodimerize with KNOTTED1-like homeobox TFs to play crucial roles in shoot meristem maintenance, but their functions are elusive in monocots. We found that maize (Zea mays) BLH12 and BLH14 have redundant but important roles in stem development. BLH12/14 interact with KNOTTED1 (KN1) in vivo and accumulate in overlapping domains in shoot meristems, young stems, and provascular bundles. Similar to kn1 loss-of-function mutants, blh12 blh14 (blh12/14) double mutants fail to maintain axillary meristems. Unique to blh12/14 is an abnormal tassel branching and precocious internode differentiation that results in dwarfism and reduced veins in stems. Micro-computed tomography observation of vascular networks revealed that blh12/14 double mutants had reduced vein number due to fewer intermediate veins in leaves and precocious anastomosis in young stems. Based on these results, we propose two functions of BLH12/14 during stem development: (1) maintaining intercalary meristems that accumulate KN1 and prevent precocious internode differentiation and (2) preventing precocious anastomosis of provascular bundles in young stems to ensure the production of sufficient independent veins.
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Affiliation(s)
- Katsutoshi Tsuda
- Experimental Farm, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Department of Genetics, School of Life Science, Graduate University for Advanced Studies, Mishima, Shizuoka 411-8540, Japan
| | - Maria-Jazmin Abraham-Juarez
- Plant Gene Expression Center, U.S. Department of Agriculture-Agricultural Research Service, Plant and Microbial Biology Department, University of California at Berkeley, Albany, California 94710
| | - Akiteru Maeno
- Mammalian Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka, 411-8540, Japan
| | - Zhaobin Dong
- Plant Gene Expression Center, U.S. Department of Agriculture-Agricultural Research Service, Plant and Microbial Biology Department, University of California at Berkeley, Albany, California 94710
| | - Dale Aromdee
- Plant Gene Expression Center, U.S. Department of Agriculture-Agricultural Research Service, Plant and Microbial Biology Department, University of California at Berkeley, Albany, California 94710
| | | | - Toshihiko Shiroishi
- Department of Genetics, School of Life Science, Graduate University for Advanced Studies, Mishima, Shizuoka 411-8540, Japan
- Mammalian Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka, 411-8540, Japan
| | - Ken-Ichi Nonomura
- Experimental Farm, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
- Department of Genetics, School of Life Science, Graduate University for Advanced Studies, Mishima, Shizuoka 411-8540, Japan
| | - Sarah Hake
- Plant Gene Expression Center, U.S. Department of Agriculture-Agricultural Research Service, Plant and Microbial Biology Department, University of California at Berkeley, Albany, California 94710
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Reyes-Rivera J, Rodríguez-Alonso G, Petrone E, Vasco A, Vergara-Silva F, Shishkova S, Terrazas T. Expression of the KNOTTED HOMEOBOX Genes in the Cactaceae Cambial Zone Suggests Their Involvement in Wood Development. FRONTIERS IN PLANT SCIENCE 2017; 8:218. [PMID: 28316604 PMCID: PMC5334636 DOI: 10.3389/fpls.2017.00218] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/06/2017] [Indexed: 05/28/2023]
Abstract
The vascular cambium is a lateral meristem that produces secondary xylem (i.e., wood) and phloem. Different Cactaceae species develop different types of secondary xylem; however, little is known about the mechanisms underlying wood formation in the Cactaceae. The KNOTTED HOMEOBOX (KNOX) gene family encodes transcription factors that regulate plant development. The role of class I KNOX genes in the regulation of the shoot apical meristem, inflorescence architecture, and secondary growth is established in a few model species, while the functions of class II KNOX genes are less well understood, although the Arabidopsis thaliana class II KNOX protein KNAT7 is known to regulate secondary cell wall biosynthesis. To explore the involvement of the KNOX genes in the enormous variability of wood in Cactaceae, we identified orthologous genes expressed in species with fibrous (Pereskia lychnidiflora and Pilosocereus alensis), non-fibrous (Ariocarpus retusus), and dimorphic (Ferocactus pilosus) wood. Both class I and class II KNOX genes were expressed in the cactus cambial zone, including one or two class I paralogs of KNAT1, as well as one or two class II paralogs of KNAT3-KNAT4-KNAT5. While the KNOX gene SHOOTMERISTEMLESS (STM) and its ortholog ARK1 are expressed during secondary growth in the Arabidopsis and Populus stem, respectively, we did not find STM orthologs in the Cactaceae cambial zone, which suggests possible differences in the vascular cambium genetic regulatory network in these species. Importantly, while two class II KNOX paralogs from the KNAT7 clade were expressed in the cambial zone of A. retusus and F. pilosus, we did not detect KNAT7 ortholog expression in the cambial zone of P. lychnidiflora. Differences in the transcriptional repressor activity of secondary cell wall biosynthesis by the KNAT7 orthologs could therefore explain the differences in wood development in the cactus species.
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Affiliation(s)
- Jorge Reyes-Rivera
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de MéxicoMexico City, Mexico
| | - Gustavo Rodríguez-Alonso
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de MéxicoCuernavaca, Mexico
| | - Emilio Petrone
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de MéxicoMexico City, Mexico
| | - Alejandra Vasco
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de MéxicoMexico City, Mexico
| | - Francisco Vergara-Silva
- Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de MéxicoMexico City, Mexico
| | - Svetlana Shishkova
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de MéxicoCuernavaca, Mexico
| | - Teresa Terrazas
- Departamento de Botánica, Instituto de Biología, Universidad Nacional Autónoma de MéxicoMexico City, Mexico
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15
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Rast-Somssich MI, Broholm S, Jenkins H, Canales C, Vlad D, Kwantes M, Bilsborough G, Dello Ioio R, Ewing RM, Laufs P, Huijser P, Ohno C, Heisler MG, Hay A, Tsiantis M. Alternate wiring of a KNOXI genetic network underlies differences in leaf development of A. thaliana and C. hirsuta. Genes Dev 2016; 29:2391-404. [PMID: 26588991 PMCID: PMC4691893 DOI: 10.1101/gad.269050.115] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this study, Rast-Somssich et al. investigated morphological differences between C. hirsuta, which has complex leaves with leaflets, and its relative, A. thaliana, which has simple leaves. By transferring single genes from one species into another under their endogenous regulatory elements, the authors show that leaf form can be modified in the recipient species, extending our knowledge of how paralogous genes are regulated in a complex eukaryote. Two interrelated problems in biology are understanding the regulatory logic and predictability of morphological evolution. Here, we studied these problems by comparing Arabidopsis thaliana, which has simple leaves, and its relative, Cardamine hirsuta, which has dissected leaves comprising leaflets. By transferring genes between the two species, we provide evidence for an inverse relationship between the pleiotropy of SHOOTMERISTEMLESS (STM) and BREVIPEDICELLUS (BP) homeobox genes and their ability to modify leaf form. We further show that cis-regulatory divergence of BP results in two alternative configurations of the genetic networks controlling leaf development. In C. hirsuta, ChBP is repressed by the microRNA164A (MIR164A)/ChCUP-SHAPED COTYLEDON (ChCUC) module and ChASYMMETRIC LEAVES1 (ChAS1), thus creating cross-talk between MIR164A/CUC and AS1 that does not occur in A. thaliana. These different genetic architectures lead to divergent interactions of network components and growth regulation in each species. We suggest that certain regulatory genes with low pleiotropy are predisposed to readily integrate into or disengage from conserved genetic networks influencing organ geometry, thus rapidly altering their properties and contributing to morphological divergence.
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Affiliation(s)
- Madlen I Rast-Somssich
- Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
| | - Suvi Broholm
- Department of Plant Sciences, University of Oxford, Oxford OX1 3BR, United Kingdom
| | - Huw Jenkins
- Department of Plant Sciences, University of Oxford, Oxford OX1 3BR, United Kingdom
| | - Claudia Canales
- Department of Plant Sciences, University of Oxford, Oxford OX1 3BR, United Kingdom
| | - Daniela Vlad
- Department of Plant Sciences, University of Oxford, Oxford OX1 3BR, United Kingdom
| | - Michiel Kwantes
- Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
| | - Gemma Bilsborough
- Department of Plant Sciences, University of Oxford, Oxford OX1 3BR, United Kingdom
| | - Raffaele Dello Ioio
- Dipartimento di Biologia e Biotecnologie, Università di Roma, Sapienza, 70-00185 Rome, Italy
| | - Rob M Ewing
- Centre for Biological Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Patrick Laufs
- Institut Jean-Pierre Bourgin, UMR1318, Institut National de la Recherche Agronomique (INRA)-Institut des Sciences et Industries du Vivant et de l'Environment (AgroParisTech), INRA Centre de Versailles-Grignon, 78026 Versailles Cedex 69117, France
| | - Peter Huijser
- Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
| | - Carolyn Ohno
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Marcus G Heisler
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Angela Hay
- Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
| | - Miltos Tsiantis
- Department of Comparative Development and Genetics, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany
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16
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Lewis MW, Hake S. Keep on growing: building and patterning leaves in the grasses. CURRENT OPINION IN PLANT BIOLOGY 2016; 29:80-6. [PMID: 26751036 DOI: 10.1016/j.pbi.2015.11.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 05/08/2023]
Abstract
Monocot leaves have unique features that arise early in their development. Maturing leaves protectively enclose younger leaves and the meristem, the pool of founder cells from which a leaf emerges. Through the maturation process, proximal sheath and distal blade tissues differentiate and are separated by the ligule and auricle structures. Here we review current research focusing on the contribution of gene regulatory factors and phytohormones on the patterning and differentiation of monocot leaves primarily focusing on research in the grasses (Poaceae). The 10000 members of the grasses include the true grain cereals (wheat, rice, maize, etc.), biofuel crops such as sugarcane, pasture grasses, and bamboo. They are the most studied of the monocots due to their tremendous agricultural and agronomic importance.
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Affiliation(s)
- Michael W Lewis
- Plant Gene Expression Center, USDA-ARS and University of California, Berkeley, United States.
| | - Sarah Hake
- Plant Gene Expression Center, USDA-ARS and University of California, Berkeley, United States
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17
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Wuddineh WA, Mazarei M, Zhang JY, Turner GB, Sykes RW, Decker SR, Davis MF, Udvardi MK, Stewart CN. Identification and Overexpression of a Knotted1-Like Transcription Factor in Switchgrass (Panicum virgatum L.) for Lignocellulosic Feedstock Improvement. FRONTIERS IN PLANT SCIENCE 2016; 7:520. [PMID: 27200006 PMCID: PMC4848298 DOI: 10.3389/fpls.2016.00520] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 04/01/2016] [Indexed: 05/18/2023]
Abstract
High biomass production and wide adaptation has made switchgrass (Panicum virgatum L.) an important candidate lignocellulosic bioenergy crop. One major limitation of this and other lignocellulosic feedstocks is the recalcitrance of complex carbohydrates to hydrolysis for conversion to biofuels. Lignin is the major contributor to recalcitrance as it limits the accessibility of cell wall carbohydrates to enzymatic breakdown into fermentable sugars. Therefore, genetic manipulation of the lignin biosynthesis pathway is one strategy to reduce recalcitrance. Here, we identified a switchgrass Knotted1 transcription factor, PvKN1, with the aim of genetically engineering switchgrass for reduced biomass recalcitrance for biofuel production. Gene expression of the endogenous PvKN1 gene was observed to be highest in young inflorescences and stems. Ectopic overexpression of PvKN1 in switchgrass altered growth, especially in early developmental stages. Transgenic lines had reduced expression of most lignin biosynthetic genes accompanied by a reduction in lignin content suggesting the involvement of PvKN1 in the broad regulation of the lignin biosynthesis pathway. Moreover, the reduced expression of the Gibberellin 20-oxidase (GA20ox) gene in tandem with the increased expression of Gibberellin 2-oxidase (GA2ox) genes in transgenic PvKN1 lines suggest that PvKN1 may exert regulatory effects via modulation of GA signaling. Furthermore, overexpression of PvKN1 altered the expression of cellulose and hemicellulose biosynthetic genes and increased sugar release efficiency in transgenic lines. Our results demonstrated that switchgrass PvKN1 is a putative ortholog of maize KN1 that is linked to plant lignification and cell wall and development traits as a major regulatory gene. Therefore, targeted overexpression of PvKN1 in bioenergy feedstocks may provide one feasible strategy for reducing biomass recalcitrance and simultaneously improving plant growth characteristics.
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Affiliation(s)
- Wegi A. Wuddineh
- Department of Plant Sciences, University of TennesseeKnoxville, TN, USA
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
| | - Mitra Mazarei
- Department of Plant Sciences, University of TennesseeKnoxville, TN, USA
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
| | - Ji-Yi Zhang
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
- Plant Biology Division, Samuel Roberts Noble FoundationArdmore, OK, USA
| | - Geoffrey B. Turner
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
- National Renewable Energy Laboratory, GoldenCO, USA
| | - Robert W. Sykes
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
- National Renewable Energy Laboratory, GoldenCO, USA
| | - Stephen R. Decker
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
- National Renewable Energy Laboratory, GoldenCO, USA
| | - Mark F. Davis
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
- National Renewable Energy Laboratory, GoldenCO, USA
| | - Michael K. Udvardi
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
- Plant Biology Division, Samuel Roberts Noble FoundationArdmore, OK, USA
| | - C. Neal Stewart
- Department of Plant Sciences, University of TennesseeKnoxville, TN, USA
- BioEnergy Science Center, Oak Ridge National LaboratoryOak Ridge, TN, USA
- *Correspondence: C. Neal Stewart Jr.,
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18
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Pautler M, Eveland AL, LaRue T, Yang F, Weeks R, Lunde C, Je BI, Meeley R, Komatsu M, Vollbrecht E, Sakai H, Jackson D. FASCIATED EAR4 encodes a bZIP transcription factor that regulates shoot meristem size in maize. THE PLANT CELL 2015; 27:104-20. [PMID: 25616871 PMCID: PMC4330574 DOI: 10.1105/tpc.114.132506] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/04/2014] [Accepted: 01/07/2015] [Indexed: 05/20/2023]
Abstract
Plant architecture is dictated by precise control of meristematic activity. In the shoot, an imbalance in positive or negative maintenance signals can result in a fasciated or enlarged meristem phenotype. fasciated ear4 (fea4) is a semidwarfed mutant with fasciated ears and tassels as well as greatly enlarged vegetative and inflorescence meristems. We identified FEA4 as a bZIP transcription factor, orthologous to Arabidopsis thaliana PERIANTHIA. FEA4 was expressed in the peripheral zone of the vegetative shoot apical meristem and in the vasculature of immature leaves and conspicuously excluded from the stem cell niche at the tip of the shoot apical meristem and from incipient leaf primordia. Following the transition to reproductive fate, FEA4 was expressed throughout the entire inflorescence and floral meristems. Native expression of a functional YFP:FEA4 fusion recapitulated this pattern of expression. We used chromatin immunoprecipitation-sequencing to identify 4060 genes proximal to FEA4 binding sites, including ones that were potentially bound and modulated by FEA4 based on transcriptional changes in fea4 mutant ears. Our results suggest that FEA4 promotes differentiation in the meristem periphery by regulating auxin-based responses and genes associated with leaf differentiation and polarity, potentially in opposition to factors such as KNOTTED1 and WUSCHEL.
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Affiliation(s)
- Michael Pautler
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Andrea L Eveland
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Therese LaRue
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Fang Yang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Rebecca Weeks
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50010
| | - China Lunde
- University of California, Berkeley, California 94720
| | - Byoung Il Je
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | - Robert Meeley
- DuPont Pioneer, Agricultural Biotechnology, Johnston, Iowa 50131
| | - Mai Komatsu
- DuPont Pioneer, Agricultural Biotechnology, Wilmington, Delaware 19803
| | - Erik Vollbrecht
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50010
| | - Hajime Sakai
- DuPont Pioneer, Agricultural Biotechnology, Wilmington, Delaware 19803
| | - David Jackson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
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19
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Abstract
The shoot apical meristem contains a pool of undifferentiated stem cells and generates all above-ground organs of the plant. During vegetative growth, cells differentiate from the meristem to initiate leaves while the pool of meristematic cells is preserved; this balance is determined in part by genetic regulatory mechanisms. To assess vegetative meristem growth and genetic control in Zea mays, we investigated its morphology at multiple time points and identified three stages of growth. We measured meristem height, width, plastochron internode length, and associated traits from 86 individuals of the intermated B73 × Mo17 recombinant inbred line population. For meristem height-related traits, the parents exhibited markedly different phenotypes, with B73 being very tall, Mo17 short, and the population distributed between. In the outer cell layer, differences appeared to be related to number of cells rather than cell size. In contrast, B73 and Mo17 were similar in meristem width traits and plastochron internode length, with transgressive segregation in the population. Multiple loci (6−9 for each trait) were mapped, indicating meristem architecture is controlled by many regions; none of these coincided with previously described mutants impacting meristem development. Major loci for height and width explaining 16% and 19% of the variation were identified on chromosomes 5 and 8, respectively. Significant loci for related traits frequently coincided, whereas those for unrelated traits did not overlap. With the use of three near-isogenic lines, a locus explaining 16% of the parental variation in meristem height was validated. Published expression data were leveraged to identify candidate genes in significant regions.
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20
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Zhou C, Han L, Li G, Chai M, Fu C, Cheng X, Wen J, Tang Y, Wang ZY. STM/BP-Like KNOXI Is Uncoupled from ARP in the Regulation of Compound Leaf Development in Medicago truncatula. THE PLANT CELL 2014; 26:1464-1479. [PMID: 24781113 PMCID: PMC4036565 DOI: 10.1105/tpc.114.123885] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 03/31/2014] [Accepted: 04/10/2014] [Indexed: 05/21/2023]
Abstract
Class I KNOTTED-like homeobox (KNOXI) genes are critical for the maintenance of the shoot apical meristem. The expression domain of KNOXI is regulated by ASYMMETRIC LEAVES1/ROUGHSHEATH2/PHANTASTICA (ARP) genes, which are associated with leaf morphology. In the inverted repeat-lacking clade (IRLC) of Fabaceae, the orthologs of LEAFY (LFY) function in place of KNOXI to regulate compound leaf development. Here, we characterized loss-of-function mutants of ARP (PHAN) and SHOOTMERISTEMLESS (STM)- and BREVIPEDICELLUS (BP)-like KNOXI in the model IRLC legume species Medicago truncatula. The function of ARP genes is species specific. The repression of STM/BP-like KNOXI genes in leaves is not mediated by PHAN, and no suppression of PHAN by STM/BP-like KNOXI genes was observed either, indicating that STM/BP-like KNOXI genes are uncoupled from PHAN in M. truncatula. Furthermore, comparative analyses of phenotypic output in response to ectopic expression of KNOXI and the M. truncatula LFY ortholog, SINGLE LEAFLET1 (SGL1), reveal that KNOXI and SGL1 regulate parallel pathways in leaf development. We propose that SGL1 probably functions in a stage-specific manner in the regulation of the indeterminate state of developing leaves in M. truncatula.
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Affiliation(s)
- Chuanen Zhou
- Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, Shandong 250100, P.R. China
| | - Lu Han
- School of Medical and Life Science, University of Jinan, Jinan, Shandong 250022, P.R. China
| | - Guifen Li
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | - Maofeng Chai
- Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | - Chunxiang Fu
- Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | - Xiaofei Cheng
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | - Jiangqi Wen
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | - Yuhong Tang
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
| | - Zeng-Yu Wang
- Forage Improvement Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401
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