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Jun SE, Cho KH, Schaffrath R, Kim GT. Evolutionary Conservation in Protein-Protein Interactions and Structures of the Elongator Sub-Complex ELP456 from Arabidopsis and Yeast. Int J Mol Sci 2024; 25:4370. [PMID: 38673955 PMCID: PMC11050213 DOI: 10.3390/ijms25084370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/09/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
The Elongator complex plays a pivotal role in the wobble uridine modification of the tRNA anticodon. Comprising two sets of six distinct subunits, namely, Elongator proteins (ELP1-ELP6) and associated proteins, the holo-Elongator complex demonstrates remarkable functional and structural conservation across eukaryotes. However, the precise details of the evolutionary conservation of the holo-Elongator complex and its individual sub-complexes (i.e., ELP123; ELP456) in plants remain limited. In this study, we conducted an in vivo analysis of protein-protein interactions among Arabidopsis ELP4, ELP5, and ELP6 proteins. Additionally, we predicted their structural configurations and performed a comparative analysis with the structure of the yeast Elp456 sub-complex. Protein-protein interaction analysis revealed that AtELP4 interacts with AtELP6 but not directly with AtELP5. Furthermore, we found that the Arabidopsis Elongator-associated protein, Deformed Roots and Leaves 1 (DRL1), did not directly bind to AtELP proteins. The structural comparison of the ELP456 sub-complex between Arabidopsis and yeast demonstrated high similarity, encompassing the RecA-ATPase fold and the positions of hydrogen bonds, despite their relatively low sequence homology. Our findings suggest that Arabidopsis ELP4, ELP5, and ELP6 proteins form a heterotrimer, with ELP6 serving as a bridge, indicating high structural conservation between the ELP456 sub-complexes from Arabidopsis and yeast.
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Affiliation(s)
- Sang Eun Jun
- Department of Molecular Genetics, Dong-A University, Busan 49315, Republic of Korea (K.-H.C.)
| | - Kiu-Hyung Cho
- Department of Molecular Genetics, Dong-A University, Busan 49315, Republic of Korea (K.-H.C.)
- Gyeongbuk Institute for Bioindustry, Andong 36618, Republic of Korea
| | - Raffael Schaffrath
- Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany;
| | - Gyung-Tae Kim
- Department of Molecular Genetics, Dong-A University, Busan 49315, Republic of Korea (K.-H.C.)
- Graduate School of Applied Bioscience, Dong-A University, Busan 49315, Republic of Korea
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Jun SE, Shim JS, Park HJ. Beyond NPK: Mineral Nutrient-Mediated Modulation in Orchestrating Flowering Time. Plants (Basel) 2023; 12:3299. [PMID: 37765463 PMCID: PMC10535918 DOI: 10.3390/plants12183299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/11/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023]
Abstract
Flowering time in plants is a complex process regulated by environmental conditions such as photoperiod and temperature, as well as nutrient conditions. While the impact of major nutrients like nitrogen, phosphorus, and potassium on flowering time has been well recognized, the significance of micronutrient imbalances and their deficiencies should not be neglected because they affect the floral transition from the vegetative stage to the reproductive stage. The secondary major nutrients such as calcium, magnesium, and sulfur participate in various aspects of flowering. Micronutrients such as boron, zinc, iron, and copper play crucial roles in enzymatic reactions and hormone biosynthesis, affecting flower development and reproduction as well. The current review comprehensively explores the interplay between microelements and flowering time, and summarizes the underlying mechanism in plants. Consequently, a better understanding of the interplay between microelements and flowering time will provide clues to reveal the roles of microelements in regulating flowering time and to improve crop reproduction in plant industries.
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Affiliation(s)
- Sang Eun Jun
- Department of Molecular Genetics, Dong-A University, Busan 49315, Republic of Korea;
| | - Jae Sun Shim
- School of Biological Science and Technology, College of Natural Sciences, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Hee Jin Park
- Department of Biological Sciences and Research Center of Ecomimetics, College of Natural Sciences, Chonnam National University, Gwangju 61186, Republic of Korea
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Jun SE, Cho KH, Manzoor MA, Hwang TY, Kim YS, Schaffrath R, Kim GT. AtELP4 a subunit of the Elongator complex in Arabidopsis, mediates cell proliferation and dorsoventral polarity during leaf morphogenesis. Front Plant Sci 2022; 13:1033358. [PMID: 36340367 PMCID: PMC9634574 DOI: 10.3389/fpls.2022.1033358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
The Elongator complex in eukaryotes has conserved tRNA modification functions and contributes to various physiological processes such as transcriptional control, DNA replication and repair, and chromatin accessibility. ARABIDOPSIS ELONGATOR PROTEIN 4 (AtELP4) is one of the six subunits (AtELP1-AtELP6) in Arabidopsis Elongator. In addition, there is an Elongator-associated protein, DEFORMED ROOTS AND LEAVES 1 (DRL1), whose homolog in yeast (Kti12) binds tRNAs. In this study, we explored the functions of AtELP4 in plant-specific aspects such as leaf morphogenesis and evolutionarily conserved ones between yeast and Arabidopsis. ELP4 comparison between yeast and Arabidopsis revealed that plant ELP4 possesses not only a highly conserved P-loop ATPase domain but also unknown plant-specific motifs. ELP4 function is partially conserved between Arabidopsis and yeast in the growth sensitivity toward caffeine and elevated cultivation temperature. Either single Atelp4 or drl1-102 mutants and double Atelp4 drl1-102 mutants exhibited a reduction in cell proliferation and changed the adaxial-abaxial polarity of leaves. In addition, the single Atelp4 and double Atelp4 drl1-102 mutants showed remarkable downward curling at the whole part of leaf blades in contrast to wild-type leaf blades. Furthermore, our genetic study revealed that AtELP4 might epistatically act on DRL1 in the regulation of cell proliferation and dorsoventral polarity in leaves. Taken together, we suggest that AtELP4 as part of the plant Elongator complex may act upstream of a regulatory pathway for adaxial-abaxial polarity and cell proliferation during leaf development.
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Affiliation(s)
- Sang Eun Jun
- Department of Molecular Genetics, Dong-A University, Busan, South Korea
| | - Kiu-Hyung Cho
- Department of Molecular Genetics, Dong-A University, Busan, South Korea
| | | | - Tae Young Hwang
- Graduate School of Applied Bioscience, Dong-A University, Busan, South Korea
| | - Youn Soo Kim
- Graduate School of Applied Bioscience, Dong-A University, Busan, South Korea
| | - Raffael Schaffrath
- Institut für Biologie, Fachgebiet Mikrobiologie, Universität Kassel, Kassel, Germany
| | - Gyung-Tae Kim
- Department of Molecular Genetics, Dong-A University, Busan, South Korea
- Graduate School of Applied Bioscience, Dong-A University, Busan, South Korea
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Jun SE, Kim JH, Hwang JY, Huynh Le TT, Kim GT. ORESARA15 Acts Synergistically with ANGUSTIFOLIA3 and Separately from AINTEGUMENTA to Promote Cell Proliferation during Leaf Growth. Int J Mol Sci 2019; 21:ijms21010241. [PMID: 31905806 PMCID: PMC6981824 DOI: 10.3390/ijms21010241] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/24/2019] [Accepted: 12/25/2019] [Indexed: 12/16/2022] Open
Abstract
Developing leaves undergo sequential coordinated cell proliferation and cell expansion to determine their final size and shape. Although several important regulators of cell proliferation have been reported, the gene network regulating leaf developmental processes remains unclear. Previously, we showed that ORESARA15 (ORE15) positively regulates the rate and duration of cell proliferation by promoting the expression of direct targets, GROWTH-REGULATING FACTOR (GRF) transcription factors, during leaf growth. In the current study, we examined the spatiotemporal patterns of ORE15 expression and determined that ORE15 expression partially overlapped with AN3/GIF1 and ANT expression along the midvein in the proximal region of the leaf blade in young leaves. Genetic analysis revealed that ORE15 may function synergistically with AN3 to control leaf growth as a positive regulator of cell proliferation. Our molecular and genetic studies are the first to suggest the importance of functional redundancies between ORE15 and AN3, and between AN3 and ANT in cell proliferation regulatory pathway during leaf growth.
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Affiliation(s)
- Sang Eun Jun
- Department of Molecular Genetics, Dong-A University, Busan 49315, Korea; (S.E.J.); (J.Y.H.)
| | - Jin Hee Kim
- Subtropical Horticulture Research Institute, Jeju National University, Jeju 63243, Korea;
| | - Ji Young Hwang
- Department of Molecular Genetics, Dong-A University, Busan 49315, Korea; (S.E.J.); (J.Y.H.)
| | - Thien Tu Huynh Le
- Department of Applied Bioscience, Graduate School of Natural Science, Dong-A University, Busan 49315, Korea;
| | - Gyung-Tae Kim
- Department of Molecular Genetics, Dong-A University, Busan 49315, Korea; (S.E.J.); (J.Y.H.)
- Department of Applied Bioscience, Graduate School of Natural Science, Dong-A University, Busan 49315, Korea;
- Correspondence: ; Tel.: +82-51-200-7519
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Yeom WW, Kim HJ, Lee KR, Cho HS, Kim JY, Jung HW, Oh SW, Jun SE, Kim HU, Chung YS. Increased Production of α-Linolenic Acid in Soybean Seeds by Overexpression of Lesquerella FAD3-1. Front Plant Sci 2019; 10:1812. [PMID: 32082356 PMCID: PMC7005135 DOI: 10.3389/fpls.2019.01812] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/27/2019] [Indexed: 05/20/2023]
Abstract
Soybean is a major crop that is used as a source of vegetable oil for human use. To develop transgenic soybean with high α-linolenic acid (ALA; 18:3) content, the FAD3-1 gene isolated from lesquerella (Physaria fendleri) was used to construct vectors with two different seed-specific promoters, soybean β-conglycinin (Pβ-con) and kidney bean phaseolin (Pphas), and one constitutive cauliflower mosaic virus 35S promoter (P35S). The corresponding vectors were used for Agrobacterium-mediated transformation of imbibed mature half seeds. The transformation efficiency was approximately 2%, 1%, and 3% and 21, 7, and 17 transgenic plants were produced, respectively. T-DNA insertion and expression of the transgene were confirmed from most of the transgenic plants by polymerase chain reaction (PCR), quantitative real-time PCR (qPCR), reverse transcription PCR (RT-PCR), and Southern blot analysis. The fatty acid composition of soybean seeds was analyzed by gas chromatography. The 18:3 content in the transgenic generation T1 seeds was increased 7-fold in Pβ-con:PfFAD3-1, 4-fold in Pphas : PfFAD3-1, and 1.6-fold in P35S:PfFAD3-1 compared to the 18:3 content in soybean "Kwangankong". The increased content of 18:3 in the Pβ-con:PfFAD3-1 soybean (T1) resulted in a 52.6% increase in total fatty acids, with a larger decrease in 18:1 content than 18:2 content. The increase in 18:3 content was also maintained and reached 42% in the Pphas : PfFAD3-1 transgenic generation T2. Investigations of the agronomic traits of 12 Pβ-con:PfFAD3-1 transgenic lines (T1) revealed that plant height, number of branches, nodes, pods, total seeds, and total seed weight were significantly higher in several transgenic lines than those in non-transgenic soybean. Especially, an increase in seed size was observed upon expression of the PfFAD3-1 gene with the β-conglycinin promoter, and 6%-14% higher seed lengths were measured from the transgenic lines.
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Affiliation(s)
- Wan Woo Yeom
- Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University, Busan, South Korea
| | - Hye Jeong Kim
- Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University, Busan, South Korea
| | - Kyeong-Ryeol Lee
- Department of Agricultural Biotechnology, National Institute of Agricultural Science, Rural Development Administration, Jeonju, South Korea
| | - Hyun Suk Cho
- Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University, Busan, South Korea
| | - Jin-Young Kim
- Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University, Busan, South Korea
| | - Ho Won Jung
- Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University, Busan, South Korea
| | - Seon-Woo Oh
- Biosafety Division, National Institute of Agricultural Science, Rural Development Administration, Jeonju, South Korea
| | - Sang Eun Jun
- Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University, Busan, South Korea
| | - Hyun Uk Kim
- Department of Bioindustry and Bioresource Engineering, Plant Engineering Research Institute, Sejong University, Seoul, South Korea
- *Correspondence: Hyun Uk Kim, ; Young-Soo Chung,
| | - Young-Soo Chung
- Department of Molecular Genetics, College of Natural Resources and Life Science, Dong-A University, Busan, South Korea
- *Correspondence: Hyun Uk Kim, ; Young-Soo Chung,
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Kim JH, Kim J, Jun SE, Park S, Timilsina R, Kwon DS, Kim Y, Park SJ, Hwang JY, Nam HG, Kim GT, Woo HR. ORESARA15, a PLATZ transcription factor, mediates leaf growth and senescence in Arabidopsis. New Phytol 2018; 220:609-623. [PMID: 29949656 DOI: 10.1111/nph.15291] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 05/24/2018] [Indexed: 05/12/2023]
Abstract
Plant leaves undergo a series of developmental changes from leaf primordium initiation through growth and maturation to senescence throughout their life span. Although the mechanisms underlying leaf senescence have been intensively elucidated, our knowledge of the interrelationship between early leaf development and senescence is still fragmentary. We isolated the oresara15-1Dominant (ore15-1D) mutant, which had an extended leaf longevity and an enlarged leaf size, from activation-tagged lines of Arabidopsis. Plasmid rescue identified that ORE15 encodes a PLANT A/T-RICH SEQUENCE- AND ZINC-BINDING PROTEIN family transcription factor. Phenotypes of ore15-1D and ore15-2, a loss-of-function mutant, were evaluated through physiological and anatomical analyses. Microarray, quantitative reverse transcription polymerase chain reaction, and chromatin immunoprecipitation as well as genetic analysis were employed to reveal the molecular mechanism of ORE15 in the regulation of leaf growth and senescence. ORE15 enhanced leaf growth by promoting the rate and duration of cell proliferation in the earlier stage and suppressed leaf senescence in the later stage by modulating the GROWTH-REGULATING FACTOR (GRF)/GRF-INTERACTING FACTOR regulatory pathway. Our study highlighted a molecular conjunction through ORE15 between growth and senescence, which are two temporally separate developmental processes during leaf life span.
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Affiliation(s)
- Jin Hee Kim
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Korea
| | - Jeongsik Kim
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Korea
| | - Sang Eun Jun
- Department of Molecular Biotechnology, Dong-A University, Busan, 49315, Korea
| | - Sanghoon Park
- Department of New Biology, DGIST, Daegu, 42988, Korea
| | | | - Da Som Kwon
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Korea
| | - Yongmin Kim
- Department of New Biology, DGIST, Daegu, 42988, Korea
- Department of Biology, Chungnam National University, Daejeon, 34134, Korea
| | - Sung-Jin Park
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Korea
| | - Ji Young Hwang
- Department of Molecular Biotechnology, Dong-A University, Busan, 49315, Korea
| | - Hong Gil Nam
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 42988, Korea
- Department of New Biology, DGIST, Daegu, 42988, Korea
| | - Gyung-Tae Kim
- Department of Molecular Biotechnology, Dong-A University, Busan, 49315, Korea
| | - Hye Ryun Woo
- Department of New Biology, DGIST, Daegu, 42988, Korea
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Mehlgarten C, Prochaska H, Hammermeister A, Abdel-Fattah W, Wagner M, Krutyhołowa R, Jun SE, Kim GT, Glatt S, Breunig KD, Stark MJR, Schaffrath R. Use of a Yeast tRNase Killer Toxin to Diagnose Kti12 Motifs Required for tRNA Modification by Elongator. Toxins (Basel) 2017; 9:toxins9090272. [PMID: 28872616 PMCID: PMC5618205 DOI: 10.3390/toxins9090272] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/29/2017] [Accepted: 09/03/2017] [Indexed: 01/23/2023] Open
Abstract
Saccharomyces cerevisiae cells are killed by zymocin, a tRNase ribotoxin complex from Kluyveromyces lactis, which cleaves anticodons and inhibits protein synthesis. Zymocin’s action requires specific chemical modification of uridine bases in the anticodon wobble position (U34) by the Elongator complex (Elp1-Elp6). Hence, loss of anticodon modification in mutants lacking Elongator or related KTI (K. lactisToxin Insensitive) genes protects against tRNA cleavage and confers resistance to the toxin. Here, we show that zymocin can be used as a tool to genetically analyse KTI12, a gene previously shown to code for an Elongator partner protein. From a kti12 mutant pool of zymocin survivors, we identify motifs in Kti12 that are functionally directly coupled to Elongator activity. In addition, shared requirement of U34 modifications for nonsense and missense tRNA suppression (SUP4; SOE1) strongly suggests that Kti12 and Elongator cooperate to assure proper tRNA functioning. We show that the Kti12 motifs are conserved in plant ortholog DRL1/ELO4 from Arabidopsis thaliana and seem to be involved in binding of cofactors (e.g., nucleotides, calmodulin). Elongator interaction defects triggered by mutations in these motifs correlate with phenotypes typical for loss of U34 modification. Thus, tRNA modification by Elongator appears to require physical contact with Kti12, and our preliminary data suggest that metabolic signals may affect proper communication between them.
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Affiliation(s)
- Constance Mehlgarten
- Institut für Biologie, Martin Luther Universität Halle-Wittenberg, Weinbergweg 10, 06120 Halle/Saale, Germany.
| | - Heike Prochaska
- Institut für Biologie, Martin Luther Universität Halle-Wittenberg, Weinbergweg 10, 06120 Halle/Saale, Germany.
| | - Alexander Hammermeister
- Institut für Biologie, FG Mikrobiologie, Universität Kassel, Heirich-Plett-Str. 40, 34132 Kassel, Germany.
| | - Wael Abdel-Fattah
- Institut für Biologie, FG Mikrobiologie, Universität Kassel, Heirich-Plett-Str. 40, 34132 Kassel, Germany.
| | - Melanie Wagner
- Institut für Biologie, Martin Luther Universität Halle-Wittenberg, Weinbergweg 10, 06120 Halle/Saale, Germany.
| | - Rościsław Krutyhołowa
- Max Planck Research Group at the Malopolska Centre of Biotechnology, Jagiellonian University, 31-007 Krakow, Poland.
- Department of Cell Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 31-007 Krakow, Poland.
| | - Sang Eun Jun
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714, Korea.
| | - Gyung-Tae Kim
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714, Korea.
| | - Sebastian Glatt
- Max Planck Research Group at the Malopolska Centre of Biotechnology, Jagiellonian University, 31-007 Krakow, Poland.
| | - Karin D Breunig
- Institut für Biologie, Martin Luther Universität Halle-Wittenberg, Weinbergweg 10, 06120 Halle/Saale, Germany.
| | - Michael J R Stark
- Centre for Gene Regulation & Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
| | - Raffael Schaffrath
- Institut für Biologie, Martin Luther Universität Halle-Wittenberg, Weinbergweg 10, 06120 Halle/Saale, Germany.
- Institut für Biologie, FG Mikrobiologie, Universität Kassel, Heirich-Plett-Str. 40, 34132 Kassel, Germany.
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Jun SE, Cho KH, Hwang JY, Abdel-Fattah W, Hammermeister A, Schaffrath R, Bowman JL, Kim GT. Comparative analysis of the conserved functions of Arabidopsis DRL1 and yeast KTI12. Mol Cells 2015; 38:243-50. [PMID: 25518926 PMCID: PMC4363724 DOI: 10.14348/molcells.2015.2297] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 12/03/2014] [Accepted: 12/03/2014] [Indexed: 12/18/2022] Open
Abstract
Patterning of the polar axis during the early leaf developmental stage is established by cell-to-cell communication between the shoot apical meristem (SAM) and the leaf primordia. In a previous study, we showed that the DRL1 gene, which encodes a homolog of the Elongator-associated protein KTI12 of yeast, acts as a positive regulator of adaxial leaf patterning and shoot meristem activity. To determine the evolutionally conserved functions of DRL1, we performed a comparison of the deduced amino acid sequence of DRL1 and its yeast homolog, KTI12, and found that while overall homology was low, well-conserved domains were presented. DRL1 contained two conserved plant-specific domains. Expression of the DRL1 gene in a yeast KTI12-deficient yeast mutant suppressed the growth retardation phenotype, but did not rescue the caffeine sensitivity, indicating that the role of Arabidopsis Elongator-associated protein is partially conserved with yeast KTI12, but may have changed between yeast and plants in response to caffeine during the course of evolution. In addition, elevated expression of DRL1 gene triggered zymocin sensitivity, while overexpression of KTI12 maintained zymocin resistance, indicating that the function of Arabidopsis DRL1 may not overlap with yeast KTI12 with regards to toxin sensitivity. In this study, expression analysis showed that class-I KNOX genes were downregulated in the shoot apex, and that YAB and KAN were upregulated in leaves of the Arabidopsis drl1-101 mutant. Our results provide insight into the communication network between the SAM and leaf primordia required for the establishment of leaf polarity by mediating histone acetylation or through other mechanisms.
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Affiliation(s)
- Sang Eun Jun
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714,
Korea
| | - Kiu-Hyung Cho
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714,
Korea
| | - Ji-Young Hwang
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714,
Korea
| | - Wael Abdel-Fattah
- Institut für Biologie, FG Mikrobiologie, Universität Kassel,
Germany
| | | | - Raffael Schaffrath
- Department of Genetics, University of Leicester,
UK
- Institut für Biologie, FG Mikrobiologie, Universität Kassel,
Germany
| | - John L. Bowman
- School of Biological Sciences, Monash University, Melbourne,
Australia
| | - Gyung-Tae Kim
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714,
Korea
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Hur YS, Um JH, Kim S, Kim K, Park HJ, Lim JS, Kim WY, Jun SE, Yoon EK, Lim J, Ohme-Takagi M, Kim D, Park J, Kim GT, Cheon CI. Arabidopsis thaliana homeobox 12 (ATHB12), a homeodomain-leucine zipper protein, regulates leaf growth by promoting cell expansion and endoreduplication. New Phytol 2015; 205:316-28. [PMID: 25187356 DOI: 10.1111/nph.12998] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 07/21/2014] [Indexed: 05/07/2023]
Abstract
Arabidopsis thaliana homeobox 12 (ATHB12), a homeodomain-leucine zipper class I (HD-Zip I) gene, is highly expressed in leaves and stems, and induced by abiotic stresses, but its role in development remains obscure. To understand its function during plant development, we studied the effects of loss and gain of function. Expression of ATHB12 fused to the EAR-motif repression domain (SRDX) - P35 S ::ATHB12SRDX (A12SRDX) and PATHB 12 ::ATHB12SRDX - slowed both leaf and root growth, while the growth of ATHB12-overexpressing seedlings (A12OX) was accelerated. Microscopic examination revealed changes in the size and number of leaf cells. Ploidy was reduced in A12SRDX plants, accompanied by decreased cell expansion and increased cell numbers. By contrast, cell size was increased in A12OX plants, along with increased ploidy and elevated expression of cell cycle switch 52s (CCS52s), which are positive regulators of endoreduplication, indicating that ATHB12 promotes leaf cell expansion and endoreduplication. Overexpression of ATHB12 led to decreased phosphorylation of Arabidopsis thaliana ribosomal protein S6 (AtRPS6), a regulator of cell growth. In addition, induction of ATHB12 in the presence of cycloheximide increased the expression of several genes related to cell expansion, such as EXPANSIN A10 (EXPA10) and DWARF4 (DWF4). Our findings strongly suggest that ATHB12 acts as a positive regulator of endoreduplication and cell growth during leaf development.
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Affiliation(s)
- Yoon-Sun Hur
- Department of Biological Science, Sookmyung Women's University, Seoul, 140-742, Korea
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Jun SE, Okushima Y, Nam J, Umeda M, Kim GT. Kip-related protein 3 is required for control of endoreduplication in the shoot apical meristem and leaves of Arabidopsis. Mol Cells 2013; 35:47-53. [PMID: 23314608 PMCID: PMC3887850 DOI: 10.1007/s10059-013-2270-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 11/05/2012] [Accepted: 11/06/2012] [Indexed: 11/29/2022] Open
Abstract
The cell cycle plays an important role in the development and adaptation of multicellular organisms; specifically, it allows them to optimally adjust their architecture in response to environmental changes. Kip-related proteins (KRPs) are important negative regulators of cyclin-dependent kinases (CDKs), which positively control the cell cycle during plant development. The Arabidopsis genome possesses seven KRP genes with low sequence similarity and distinct expression patterns; however, why Arabidopsis needs seven KRP genes and how these genes function in cell cycle regulation are unknown. Here, we focused on the characterization of KRP3, which was found to have unique functions in the shoot apical meristem (SAM) and leaves. KRP3 protein was localized to the SAM, including the ground meristem and vascular tissues in the ground part of the SAM and cotyledons. In addition, KRP3 protein was stabilized when treated with MG132, an inhibitor of the 26S proteasome, indicating that the protein may be regulated by 26S proteasome-mediated protein degradation. KRP3-overexpressing (KRP3 OE) transgenic plants showed reduced organ size, serrated leaves, and reduced fertility. Interestingly, the KRP3 OE transgenic plants showed a significant reduction in the size of the SAM with alterations in cell arrangement. In addition, compared to the wild type, the KRP3 OE transgenic plants had a higher DNA ploidy level in the SAM and leaves. Taken together, our data suggest that KRP3 plays important regulatory roles in the cell cycle and endoreduplication in the SAM and leaves.
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Affiliation(s)
- Sang Eun Jun
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714,
Korea
| | | | - Jaesung Nam
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714,
Korea
| | | | - Gyung-Tae Kim
- Department of Molecular Biotechnology, Dong-A University, Busan 604-714,
Korea
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Kee JJ, Jun SE, Baek SA, Lee TS, Cho MR, Hwang HS, Lee SC, Kim J, Kim GT, Im KH. Overexpression of the downward leaf curling (DLC) gene from melon changes leaf morphology by controlling cell size and shape in Arabidopsis leaves. Mol Cells 2009; 28:93-8. [PMID: 19669629 DOI: 10.1007/s10059-009-0105-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 06/10/2009] [Accepted: 06/15/2009] [Indexed: 11/25/2022] Open
Abstract
A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology.
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Affiliation(s)
- Jae-Jun Kee
- Department of Biology, University of Incheon, Incheon, 402-749, Korea
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