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Chocano-Coralla EJ, Vidali L. Myosin XI, a model of its conserved role in plant cell tip growth. Biochem Soc Trans 2024; 52:505-515. [PMID: 38629612 DOI: 10.1042/bst20220783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 03/21/2024] [Accepted: 03/26/2024] [Indexed: 04/25/2024]
Abstract
In eukaryotic cells, organelle and vesicle transport, positioning, and interactions play crucial roles in cytoplasmic organization and function. These processes are governed by intracellular trafficking mechanisms. At the core of that trafficking, the cytoskeleton and directional transport by motor proteins stand out as its key regulators. Plant cell tip growth is a well-studied example of cytoplasm organization by polarization. This polarization, essential for the cell's function, is driven by the cytoskeleton and its associated motors. This review will focus on myosin XI, a molecular motor critical for vesicle trafficking and polarized plant cell growth. We will center our discussion on recent data from the moss Physcomitrium patens and the liverwort Marchantia polymorpha. The biochemical properties and structure of myosin XI in various plant species are discussed, highlighting functional conservation across species. We further explore this conservation of myosin XI function in the process of vesicle transport in tip-growing cells. Existing evidence indicates that myosin XI actively organizes actin filaments in tip-growing cells by a mechanism based on vesicle clustering at their tips. A hypothetical model is presented to explain the essential function of myosin XI in polarized plant cell growth based on vesicle clustering at the tip. The review also provides insight into the in vivo localization and dynamics of myosin XI, emphasizing its role in cytosolic calcium regulation, which influences the polymerization of F-actin. Lastly, we touch upon the need for additional research to elucidate the regulation of myosin function.
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Affiliation(s)
| | - Luis Vidali
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, U.S.A
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2
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Qian D, Li T, Zheng C, Niu Y, Niu Y, Li C, Wang M, Yang Y, An L, Xiang Y. Actin-depolymerizing factors 8 and 11 promote root hair elongation at high pH. PLANT COMMUNICATIONS 2024; 5:100787. [PMID: 38158655 PMCID: PMC10943588 DOI: 10.1016/j.xplc.2023.100787] [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: 12/10/2023] [Revised: 12/26/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
A root hair is a polarly elongated single-celled structure that derives from a root epidermal cell and functions in uptake of water and nutrients from the surrounding environment. Previous reports have demonstrated that short periods of high pH inhibit root hair extension; but the effects of long-term high-pH treatment on root hair growth are still unclear. Here, we report that the duration of root hair elongation is significantly prolonged with increasing external pH, which counteracts the effect of decreasing root hair elongation rate and ultimately produces longer root hairs, whereas loss of actin-depolymerizing factor 8 and 11 (ADF8/11) function causes shortening of root hair length at high pH (pH 7.4). Accumulation of ADF8/11 at the tips of root hairs is inhibited by high pH, and increasing environmental pH affects the actin filament (F-actin) meshwork at the root hair tip. At high pH, the tip-focused F-actin meshwork is absent in root hairs of the adf8/11 mutant, actin filaments are disordered at the adf8/11 root hair tips, and actin turnover is attenuated. Secretory and recycling vesicles do not aggregate in the apical region of adf8/11 root hairs at high pH. Together, our results suggest that, under long-term exposure to high extracellular pH, ADF8/11 may establish and maintain the tip-focused F-actin meshwork to regulate polar trafficking of secretory/recycling vesicles at the root hair tips, thereby promoting root hair elongation.
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Affiliation(s)
- Dong Qian
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Tian Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Chen Zheng
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yue Niu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yingzhi Niu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Chengying Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Muxuan Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yang Yang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Lizhe An
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yun Xiang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
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3
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Yuan G, Gao H, Yang T. Exploring the Role of the Plant Actin Cytoskeleton: From Signaling to Cellular Functions. Int J Mol Sci 2023; 24:15480. [PMID: 37895158 PMCID: PMC10607326 DOI: 10.3390/ijms242015480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/06/2023] [Accepted: 10/21/2023] [Indexed: 10/29/2023] Open
Abstract
The plant actin cytoskeleton is characterized by the basic properties of dynamic array, which plays a central role in numerous conserved processes that are required for diverse cellular functions. Here, we focus on how actins and actin-related proteins (ARPs), which represent two classical branches of a greatly diverse superfamily of ATPases, are involved in fundamental functions underlying signal regulation of plant growth and development. Moreover, we review the structure, assembly dynamics, and biological functions of filamentous actin (F-actin) from a molecular perspective. The various accessory proteins known as actin-binding proteins (ABPs) partner with F-actin to finely tune actin dynamics, often in response to various cell signaling pathways. Our understanding of the significance of the actin cytoskeleton in vital cellular activities has been furthered by comparison of conserved functions of actin filaments across different species combined with advanced microscopic techniques and experimental methods. We discuss the current model of the plant actin cytoskeleton, followed by examples of the signaling mechanisms under the supervision of F-actin related to cell morphogenesis, polar growth, and cytoplasmic streaming. Determination of the theoretical basis of how the cytoskeleton works is important in itself and is beneficial to future applications aimed at improving crop biomass and production efficiency.
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Affiliation(s)
| | | | - Tao Yang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China; (G.Y.); (H.G.)
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4
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Zhang R, Xu Y, Yi R, Shen J, Huang S. Actin cytoskeleton in the control of vesicle transport, cytoplasmic organization, and pollen tube tip growth. PLANT PHYSIOLOGY 2023; 193:9-25. [PMID: 37002825 DOI: 10.1093/plphys/kiad203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/08/2023] [Accepted: 03/17/2023] [Indexed: 06/19/2023]
Abstract
Pollen tubes extend rapidly via tip growth. This process depends on a dynamic actin cytoskeleton, which has been implicated in controlling organelle movements, cytoplasmic streaming, vesicle trafficking, and cytoplasm organization in pollen tubes. In this update review, we describe the progress in understanding the organization and regulation of the actin cytoskeleton and the function of the actin cytoskeleton in controlling vesicle traffic and cytoplasmic organization in pollen tubes. We also discuss the interplay between ion gradients and the actin cytoskeleton that regulates the spatial arrangement and dynamics of actin filaments and the organization of the cytoplasm in pollen tubes. Finally, we describe several signaling components that regulate actin dynamics in pollen tubes.
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Affiliation(s)
- Ruihui Zhang
- National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yanan Xu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ran Yi
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jiangfeng Shen
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shanjin Huang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
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5
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Jareczek JJ, Grover CE, Hu G, Xiong X, Arick Ii MA, Peterson DG, Wendel JF. Domestication over Speciation in Allopolyploid Cotton Species: A Stronger Transcriptomic Pull. Genes (Basel) 2023; 14:1301. [PMID: 37372480 DOI: 10.3390/genes14061301] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/13/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Cotton has been domesticated independently four times for its fiber, but the genomic targets of selection during each domestication event are mostly unknown. Comparative analysis of the transcriptome during cotton fiber development in wild and cultivated materials holds promise for revealing how independent domestications led to the superficially similar modern cotton fiber phenotype in upland (G. hirsutum) and Pima (G. barbadense) cotton cultivars. Here we examined the fiber transcriptomes of both wild and domesticated G. hirsutum and G. barbadense to compare the effects of speciation versus domestication, performing differential gene expression analysis and coexpression network analysis at four developmental timepoints (5, 10, 15, or 20 days after flowering) spanning primary and secondary wall synthesis. These analyses revealed extensive differential expression between species, timepoints, domestication states, and particularly the intersection of domestication and species. Differential expression was higher when comparing domesticated accessions of the two species than between the wild, indicating that domestication had a greater impact on the transcriptome than speciation. Network analysis showed significant interspecific differences in coexpression network topology, module membership, and connectivity. Despite these differences, some modules or module functions were subject to parallel domestication in both species. Taken together, these results indicate that independent domestication led G. hirsutum and G. barbadense down unique pathways but that it also leveraged similar modules of coexpression to arrive at similar domesticated phenotypes.
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Affiliation(s)
- Josef J Jareczek
- Ecology, Evolution, and Organismal Biology Department, Iowa State University, Ames, IA 50010, USA
- Biology Department, Bellarmine University, Louisville, KY 40205, USA
| | - Corrinne E Grover
- Ecology, Evolution, and Organismal Biology Department, Iowa State University, Ames, IA 50010, USA
| | - Guanjing Hu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Xianpeng Xiong
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Mark A Arick Ii
- Institute for Genomics, Biocomputing & Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Daniel G Peterson
- Institute for Genomics, Biocomputing & Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA
| | - Jonathan F Wendel
- Ecology, Evolution, and Organismal Biology Department, Iowa State University, Ames, IA 50010, USA
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6
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Wang Q, Xu Y, Zhao S, Jiang Y, Yi R, Guo Y, Huang S. Activation of actin-depolymerizing factor by CDPK16-mediated phosphorylation promotes actin turnover in Arabidopsis pollen tubes. PLoS Biol 2023; 21:e3002073. [PMID: 37011088 PMCID: PMC10101649 DOI: 10.1371/journal.pbio.3002073] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/13/2023] [Accepted: 03/11/2023] [Indexed: 04/05/2023] Open
Abstract
As the stimulus-responsive mediator of actin dynamics, actin-depolymerizing factor (ADF)/cofilin is subject to tight regulation. It is well known that kinase-mediated phosphorylation inactivates ADF/cofilin. Here, however, we found that the activity of Arabidopsis ADF7 is enhanced by CDPK16-mediated phosphorylation. We found that CDPK16 interacts with ADF7 both in vitro and in vivo, and it enhances ADF7-mediated actin depolymerization and severing in vitro in a calcium-dependent manner. Accordingly, the rate of actin turnover is reduced in cdpk16 pollen and the amount of actin filaments increases significantly at the tip of cdpk16 pollen tubes. CDPK16 phosphorylates ADF7 at Serine128 both in vitro and in vivo, and the phospho-mimetic mutant ADF7S128D has enhanced actin-depolymerizing activity compared to ADF7. Strikingly, we found that failure in the phosphorylation of ADF7 at Ser128 impairs its function in promoting actin turnover in vivo, which suggests that this phospho-regulation mechanism is biologically significant. Thus, we reveal that CDPK16-mediated phosphorylation up-regulates ADF7 to promote actin turnover in pollen.
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Affiliation(s)
- Qiannan Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yanan Xu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shuangshuang Zhao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, China
- Key Laboratory of Plant Stress, Life Science College, Shandong Normal University, Jinan, China
| | - Yuxiang Jiang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Ran Yi
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yan Guo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Shanjin Huang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
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7
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Jareczek JJ, Grover CE, Wendel JF. Cotton fiber as a model for understanding shifts in cell development under domestication. FRONTIERS IN PLANT SCIENCE 2023; 14:1146802. [PMID: 36938017 PMCID: PMC10017751 DOI: 10.3389/fpls.2023.1146802] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 02/21/2023] [Indexed: 05/27/2023]
Abstract
Cotton fiber provides the predominant plant textile in the world, and it is also a model for plant cell wall biosynthesis. The development of the single-celled cotton fiber takes place across several overlapping but discrete stages, including fiber initiation, elongation, the transition from elongation to secondary cell wall formation, cell wall thickening, and maturation and cell death. During each stage, the developing fiber undergoes a complex restructuring of genome-wide gene expression change and physiological/biosynthetic processes, which ultimately generate a strikingly elongated and nearly pure cellulose product that forms the basis of the global cotton industry. Here, we provide an overview of this developmental process focusing both on its temporal as well as evolutionary dimensions. We suggest potential avenues for further improvement of cotton as a crop plant.
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Affiliation(s)
- Josef J. Jareczek
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, United States
- Biology Department, Bellarmine University, Louisville, KY, United States
| | - Corrinne E. Grover
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, United States
| | - Jonathan F. Wendel
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, United States
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8
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Yuan J, Cheng L, Li H, An C, Wang Y, Zhang F. Physiological and protein profiling analysis provides insight into the underlying molecular mechanism of potato tuber development regulated by jasmonic acid in vitro. BMC PLANT BIOLOGY 2022; 22:481. [PMID: 36210448 PMCID: PMC9549635 DOI: 10.1186/s12870-022-03852-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 09/19/2022] [Indexed: 05/08/2023]
Abstract
BACKGROUND Jasmonates (JAs) are one of important phytohormones regulating potato tuber development. It is a complex process and the underlying molecular mechanism regulating tuber development by JAs is still limited. This study attempted to illuminate it through the potential proteomic dynamics information about tuber development in vitro regulated by exogenous JA. RESULTS A combined analysis of physiological and iTRAQ (isobaric tags for relative and absolute quantification)-based proteomic approach was performed in tuber development in vitro under exogenous JA treatments (0, 0.5, 5 and 50 μΜ). Physiological results indicated that low JA concentration (especially 5 μM) promoted tuber development, whereas higher JA concentration (50 μM) showed inhibition effect. A total of 257 differentially expressed proteins (DEPs) were identified by iTRAQ, which provided a comprehensive overview on the functional protein profile changes of tuber development regulated by JA. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that low JA concentration (especially 5 μM) exhibited the promotion effects on tuber development in various cellular processes. Some cell wall polysaccharide synthesis and cytoskeleton formation-related proteins were up-regulated by JA to promote tuber cell expansion. Some primary carbon metabolism-related enzymes were up-regulated by JA to provide sufficient metabolism intermediates and energy for tuber development. And, a large number of protein biosynthesis, degradation and assembly-related were up-regulated by JA to promote tuber protein biosynthesis and maintain strict protein quality control during tuber development. CONCLUSIONS This study is the first to integrate physiological and proteomic data to provide useful information about the JA-signaling response mechanism of potato tuber development in vitro. The results revealed that the levels of a number of proteins involved in various cellular processes were regulated by JA during tuber development. The proposed hypothetical model would explain the interaction of these DEPs that associated with tuber development in vitro regulated by JA.
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Affiliation(s)
- Jianlong Yuan
- State Key Laboratory of Aridland Crop Science, Gansu Key Laboratory of Crop Improvement & Germplasm Enhancement, College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Lixiang Cheng
- State Key Laboratory of Aridland Crop Science, Gansu Key Laboratory of Crop Improvement & Germplasm Enhancement, College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Huijun Li
- State Key Laboratory of Aridland Crop Science, Gansu Key Laboratory of Crop Improvement & Germplasm Enhancement, College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Congcong An
- State Key Laboratory of Aridland Crop Science, Gansu Key Laboratory of Crop Improvement & Germplasm Enhancement, College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China
| | - Yuping Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou, China
| | - Feng Zhang
- State Key Laboratory of Aridland Crop Science, Gansu Key Laboratory of Crop Improvement & Germplasm Enhancement, College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China.
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Naramoto S, Hata Y, Fujita T, Kyozuka J. The bryophytes Physcomitrium patens and Marchantia polymorpha as model systems for studying evolutionary cell and developmental biology in plants. THE PLANT CELL 2022; 34:228-246. [PMID: 34459922 PMCID: PMC8773975 DOI: 10.1093/plcell/koab218] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 08/25/2021] [Indexed: 05/03/2023]
Abstract
Bryophytes are nonvascular spore-forming plants. Unlike in flowering plants, the gametophyte (haploid) generation of bryophytes dominates the sporophyte (diploid) generation. A comparison of bryophytes with flowering plants allows us to answer some fundamental questions raised in evolutionary cell and developmental biology. The moss Physcomitrium patens was the first bryophyte with a sequenced genome. Many cell and developmental studies have been conducted in this species using gene targeting by homologous recombination. The liverwort Marchantia polymorpha has recently emerged as an excellent model system with low genomic redundancy in most of its regulatory pathways. With the development of molecular genetic tools such as efficient genome editing, both P. patens and M. polymorpha have provided many valuable insights. Here, we review these advances with a special focus on polarity formation at the cell and tissue levels. We examine current knowledge regarding the cellular mechanisms of polarized cell elongation and cell division, including symmetric and asymmetric cell division. We also examine the role of polar auxin transport in mosses and liverworts. Finally, we discuss the future of evolutionary cell and developmental biological studies in plants.
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Affiliation(s)
| | - Yuki Hata
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
| | - Tomomichi Fujita
- Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Junko Kyozuka
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai 980-8577, Japan
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10
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Charlot F, Goudounet G, Nogué F, Perroud PF. Physcomitrium patens Protoplasting and Protoplast Transfection. Methods Mol Biol 2022; 2464:3-19. [PMID: 35258821 DOI: 10.1007/978-1-0716-2164-6_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Protoplast production with the moss Physcomitrium (Physcomitrella) patens has a long and successful history. As a tool, it has not only been the base of reverse genetic studies covering research fields as diverse as development, metabolism, or gene network regulation but also allowed its development as a bioengineering platform for protein production. We present here a standardized protocol for protoplast production from Physcomitrium (Physcomitrella) patens protonemata. Additionally, we detail procedures for their transfection, their plating for optimal regeneration, and three alternative selection approaches. To improve the consistency of protoplast regeneration, we describe a new option for protoplast embedding. The use of an alginate matrix to regenerate moss protoplast alleviates the use of warm agarized medium. Thus, it optimizes transformed protoplast survival without any morphological detrimental effect or impact on transfection efficiency.
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Affiliation(s)
- Florence Charlot
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Guillaume Goudounet
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Fabien Nogué
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Pierre-François Perroud
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France.
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11
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Bibeau JP, Galotto G, Wu M, Tüzel E, Vidali L. Quantitative cell biology of tip growth in moss. PLANT MOLECULAR BIOLOGY 2021; 107:227-244. [PMID: 33825083 PMCID: PMC8492783 DOI: 10.1007/s11103-021-01147-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 03/25/2021] [Indexed: 05/16/2023]
Abstract
KEY MESSAGE Here we review, from a quantitative point of view, the cell biology of protonemal tip growth in the model moss Physcomitrium patens. We focus on the role of the cytoskeleton, vesicle trafficking, and cell wall mechanics, including reviewing some of the existing mathematical models of tip growth. We provide a primer for existing cell biological tools that can be applied to the future study of tip growth in moss. Polarized cell growth is a ubiquitous process throughout the plant kingdom in which the cell elongates in a self-similar manner. This process is important for nutrient uptake by root hairs, fertilization by pollen, and gametophyte development by the protonemata of bryophytes and ferns. In this review, we will focus on the tip growth of moss cells, emphasizing the role of cytoskeletal organization, cytoplasmic zonation, vesicle trafficking, cell wall composition, and dynamics. We compare some of the existing knowledge on tip growth in protonemata against what is known in pollen tubes and root hairs, which are better-studied tip growing cells. To fully understand how plant cells grow requires that we deepen our knowledge in a variety of forms of plant cell growth. We focus this review on the model plant Physcomitrium patens, which uses tip growth as the dominant form of growth at its protonemal stage. Because mosses and vascular plants shared a common ancestor more than 450 million years ago, we anticipate that both similarities and differences between tip growing plant cells will provide mechanistic information of tip growth as well as of plant cell growth in general. Towards this mechanistic understanding, we will also review some of the existing mathematical models of plant tip growth and their applicability to investigate protonemal morphogenesis. We attempt to integrate the conclusions and data across cell biology and physical modeling to our current state of knowledge of polarized cell growth in P. patens and highlight future directions in the field.
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Affiliation(s)
- Jeffrey P Bibeau
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Giulia Galotto
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Min Wu
- Department of Mathematical Sciences, Worcester Polytechnic Institute, Worcester, MA, USA
- Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Erkan Tüzel
- Bioengineering Department, Temple University, Philadelphia, PA, USA
| | - Luis Vidali
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA.
- Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA, USA.
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12
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Jaeger R, Moody LA. A fundamental developmental transition in Physcomitrium patens is regulated by evolutionarily conserved mechanisms. Evol Dev 2021; 23:123-136. [PMID: 33822471 DOI: 10.1111/ede.12376] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/09/2021] [Accepted: 03/11/2021] [Indexed: 01/15/2023]
Abstract
One of the most defining moments in history was the colonization of land by plants approximately 470 million years ago. The transition from water to land was accompanied by significant changes in the plant body plan, from those than resembled filamentous representatives of the charophytes, the sister group to land plants, to those that were morphologically complex and capable of colonizing harsher habitats. The moss Physcomitrium patens (also known as Physcomitrella patens) is an extant representative of the bryophytes, the earliest land plant lineage. The protonema of P. patens emerges from spores from a chloronemal initial cell, which can divide to self-renew to produce filaments of chloronemal cells. A chloronemal initial cell can differentiate into a caulonemal initial cell, which can divide and self-renew to produce filaments of caulonemal cells, which branch extensively and give rise to three-dimensional shoots. The process by which a chloronemal initial cell differentiates into a caulonemal initial cell is tightly regulated by auxin-induced remodeling of the actin cytoskeleton. Studies have revealed that the genetic mechanisms underpinning this transition also regulate tip growth and differentiation in diverse plant taxa. This review summarizes the known cellular and molecular mechanisms underpinning the chloronema to caulonema transition in P. patens.
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Affiliation(s)
- Richard Jaeger
- Department of Plant Sciences, University of Oxford, Oxford, UK
| | - Laura A Moody
- Department of Plant Sciences, University of Oxford, Oxford, UK
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13
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Wang Q, Yuan W, Yang X, Wang Y, Li Y, Qiao H. Role of Cofilin in Alzheimer's Disease. Front Cell Dev Biol 2020; 8:584898. [PMID: 33324642 PMCID: PMC7726191 DOI: 10.3389/fcell.2020.584898] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/26/2020] [Indexed: 01/14/2023] Open
Abstract
Alzheimer's disease (AD) is a degenerative neurological disease and has an inconspicuous onset and progressive development. Clinically, it is characterized by severe dementia manifestations, including memory impairment, aphasia, apraxia, loss of recognition, impairment of visual-spatial skills, executive dysfunction, and changes in personality and behavior. Its etiology is unknown to date. However, several cellular biological signatures of AD have been identified such as synaptic dysfunction, β-amyloid plaques, hyperphosphorylated tau, cofilin-actin rods, and Hirano bodies which are related to the actin cytoskeleton. Cofilin is one of the most affluent and common actin-binding proteins and plays a role in cell motility, migration, shape, and metabolism. They also play an important role in severing actin filament, nucleating, depolymerizing, and bundling activities. In this review, we summarize the structure of cofilins and their functional and regulating roles, focusing on the synaptic dysfunction, β-amyloid plaques, hyperphosphorylated tau, cofilin-actin rods, and Hirano bodies of AD.
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Affiliation(s)
- Qiang Wang
- College of Acupuncture and Massage, Shaanxi University of Chinese Medicine, Xianyang, China
- Shaanxi Key Laboratory of Acupuncture and Medicine, Xianyang, China
| | - Wei Yuan
- College of Acupuncture and Massage, Shaanxi University of Chinese Medicine, Xianyang, China
- Shaanxi Key Laboratory of Acupuncture and Medicine, Xianyang, China
| | - Xiaohang Yang
- College of Acupuncture and Massage, Shaanxi University of Chinese Medicine, Xianyang, China
- College of Medical Technology, Shaanxi University of Chinese Medicine, Xi’an, China
| | - Yuan Wang
- College of Acupuncture and Massage, Shaanxi University of Chinese Medicine, Xianyang, China
- Shaanxi Key Laboratory of Acupuncture and Medicine, Xianyang, China
| | - Yongfeng Li
- College of Acupuncture and Massage, Shaanxi University of Chinese Medicine, Xianyang, China
- Shaanxi Key Laboratory of Acupuncture and Medicine, Xianyang, China
| | - Haifa Qiao
- College of Acupuncture and Massage, Shaanxi University of Chinese Medicine, Xianyang, China
- Shaanxi Key Laboratory of Acupuncture and Medicine, Xianyang, China
- Xianyang Key Laboratory of Neurobiology and Acupuncture, Xi’an, China
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14
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Yu Y, Qiao L, Chen J, Rong Y, Zhao Y, Cui X, Xu J, Hou X, Dong CH. Arabidopsis REM16 acts as a B3 domain transcription factor to promote flowering time via directly binding to the promoters of SOC1 and FT. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 103:1386-1398. [PMID: 32391591 DOI: 10.1111/tpj.14807] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 04/22/2020] [Accepted: 05/01/2020] [Indexed: 05/25/2023]
Abstract
Actin depolymerizing factor (ADF) is a key modulator for dynamic organization of actin cytoskeleton. Interestingly, it was found that the ADF1 gene silencing delays flowering, but its mechanism remains unclear. In this study, ADF1 was used as a bait to screen its interacting proteins by the yeast two-hybrid (Y2H) system. One of them, the REM16 transcription factor was identified. As one of the AP2/B3-like transcriptional factor family members, the REM16 contains two B3 domains and its transcript levels kept increasing during the floral transition stage. Overexpression of REM16 accelerates flowering while silencing of REM16 delays flowering. Gene expression analysis indicated that the key flowering activation genes such as CONSTANS (CO), FLOWERING LOCUS T (FT), LEAFY (LFY) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS (SOC1) were upregulated in the REM16 overexpression lines, while the transcription of the flowering suppression gene FLOWERING LOCUS C (FLC) was decreased. In contrast, the REM16 gene silencing lines contained lower transcript levels of the CO, FT, LFY and SOC1 but higher transcript levels of the FLC compared with the wild-type plants. It was proved that REM16 could directly bind to the promoter regions of SOC1 and FT by in vitro and in vivo assays. Genetic analysis supported that REM16 acts upstream of SOC1 and FT in flowering pathways. All these studies provided strong evidence demonstrating that REM16 promotes flowering by directly activating SOC1 and FT.
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Affiliation(s)
- Yanchong Yu
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Longfei Qiao
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Jiacai Chen
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Yongheng Rong
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Yuhang Zhao
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Xiankui Cui
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Jinpeng Xu
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Xiaomin Hou
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Chun-Hai Dong
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
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15
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Ortega-Ortega Y, Carrasco-Castilla J, Juárez-Verdayes MA, Toscano-Morales R, Fonseca-García C, Nava N, Cárdenas L, Quinto C. Actin Depolymerizing Factor Modulates Rhizobial Infection and Nodule Organogenesis in Common Bean. Int J Mol Sci 2020; 21:ijms21061970. [PMID: 32183068 PMCID: PMC7139724 DOI: 10.3390/ijms21061970] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 12/28/2022] Open
Abstract
Actin plays a critical role in the rhizobium-legume symbiosis. Cytoskeletal rearrangements and changes in actin occur in response to Nod factors secreted by rhizobia during symbiotic interactions with legumes. These cytoskeletal rearrangements are mediated by diverse actin-binding proteins, such as actin depolymerization factors (ADFs). We examined the function of an ADF in the Phaseolus vulgaris-rhizobia symbiotic interaction (PvADFE). PvADFE was preferentially expressed in rhizobia-inoculated roots and nodules. PvADFE promoter activity was associated with root hairs harbouring growing infection threads, cortical cell divisions beneath root hairs, and vascular bundles in mature nodules. Silencing of PvADFE using RNA interference increased the number of infection threads in the transgenic roots, resulting in increased nodule number, nitrogen fixation activity, and average nodule diameter. Conversely, overexpression of PvADFE reduced the nodule number, nitrogen fixation activity, average nodule diameter, as well as NODULE INCEPTION (NIN) and EARLY NODULIN2 (ENOD2) transcript accumulation. Hence, changes in ADFE transcript levels affect rhizobial infection and nodulation, suggesting that ADFE is fine-tuning these processes.
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Affiliation(s)
- Yolanda Ortega-Ortega
- Departamento de Biociencias y Agrobiotecnología, Centro de Investigación en Química Aplicada-CONACYT, Saltillo 25294, Coahuila, Mexico;
| | - Janet Carrasco-Castilla
- Instituto Politécnico Nacional, Centro de Estudios Científicos y Tecnológicos 17 León, León 37358, Guanajuato, Mexico;
| | - Marco A. Juárez-Verdayes
- Departamento de Docencia, Universidad Autónoma Agraria Antonio Narro, Saltillo 25315, Coahuila, Mexico;
| | - Roberto Toscano-Morales
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA;
| | - Citlali Fonseca-García
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, UNAM, Cuernavaca 62210, Morelos, Mexico; (C.F.-G.); (N.N.); (L.C.)
| | - Noreide Nava
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, UNAM, Cuernavaca 62210, Morelos, Mexico; (C.F.-G.); (N.N.); (L.C.)
| | - Luis Cárdenas
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, UNAM, Cuernavaca 62210, Morelos, Mexico; (C.F.-G.); (N.N.); (L.C.)
| | - Carmen Quinto
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, UNAM, Cuernavaca 62210, Morelos, Mexico; (C.F.-G.); (N.N.); (L.C.)
- Correspondence:
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16
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Galotto G, Bibeau JP, Vidali L. Automated Image Acquisition and Morphological Analysis of Cell Growth Mutants in Physcomitrella patens. Methods Mol Biol 2020; 1992:307-322. [PMID: 31148047 DOI: 10.1007/978-1-4939-9469-4_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
This protocol describes the automated imaging and a quantitative analysis of the morphology of small plants from the moss Physcomitrella patens. This method can be used for the analysis of growth phenotypes produced by transient RNA interference or for the analysis of stable mutant plants. Furthermore, we describe how to acquire higher resolution images via the acquisition of a collection of multiple overlapping tiles from the same image. Information is presented to guide the investigator in the choice of vectors and basic conditions to perform transient RNA interference in moss. Detailed directions and examples for fluorescence image acquisition of small regenerating moss plants are provided. Instructions for stitching image tiles and for using an ImageJ-based macro for the quantitative morphological analysis of moss plants are also provided.
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Affiliation(s)
- Giulia Galotto
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Jeffrey P Bibeau
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Luis Vidali
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA, USA.
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17
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Tedeschi A, Dupraz S, Curcio M, Laskowski CJ, Schaffran B, Flynn KC, Santos TE, Stern S, Hilton BJ, Larson MJE, Gurniak CB, Witke W, Bradke F. ADF/Cofilin-Mediated Actin Turnover Promotes Axon Regeneration in the Adult CNS. Neuron 2019; 103:1073-1085.e6. [PMID: 31400829 DOI: 10.1016/j.neuron.2019.07.007] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/06/2019] [Accepted: 07/08/2019] [Indexed: 11/27/2022]
Abstract
Injured axons fail to regenerate in the adult CNS, which contrasts with their vigorous growth during embryonic development. We explored the potential of re-initiating axon extension after injury by reactivating the molecular mechanisms that drive morphogenetic transformation of neurons during development. Genetic loss- and gain-of-function experiments followed by time-lapse microscopy, in vivo imaging, and whole-mount analysis show that axon regeneration is fueled by elevated actin turnover. Actin depolymerizing factor (ADF)/cofilin controls actin turnover to sustain axon regeneration after spinal cord injury through its actin-severing activity. This pinpoints ADF/cofilin as a key regulator of axon growth competence, irrespective of developmental stage. These findings reveal the central role of actin dynamics regulation in this process and elucidate a core mechanism underlying axon growth after CNS trauma. Thereby, neurons maintain the capacity to stimulate developmental programs during adult life, expanding their potential for plasticity. Thus, actin turnover is a key process for future regenerative interventions.
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Affiliation(s)
- Andrea Tedeschi
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Sebastian Dupraz
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Michele Curcio
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Claudia J Laskowski
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Barbara Schaffran
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Kevin C Flynn
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Telma E Santos
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Sina Stern
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Brett J Hilton
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany
| | - Molly J E Larson
- Center for Brain and Spinal Cord Repair, Department of Neuroscience, Wexner Medical Center, The Ohio State University, 460 W. 12th Ave., Columbus, OH 43210, USA
| | - Christine B Gurniak
- Institute of Genetics, University of Bonn, Karlrobert-Kreiten-Str. 13, 53115 Bonn, Germany
| | - Walter Witke
- Institute of Genetics, University of Bonn, Karlrobert-Kreiten-Str. 13, 53115 Bonn, Germany
| | - Frank Bradke
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Sigmund-Freud-Str. 27, 53127 Bonn, Germany.
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18
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Zhang R, Qu X, Zhang M, Jiang Y, Dai A, Zhao W, Cao D, Lan Y, Yu R, Wang H, Huang S. The Balance between Actin-Bundling Factors Controls Actin Architecture in Pollen Tubes. iScience 2019; 16:162-176. [PMID: 31181400 PMCID: PMC6556835 DOI: 10.1016/j.isci.2019.05.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 04/29/2019] [Accepted: 05/21/2019] [Indexed: 11/19/2022] Open
Abstract
How actin-bundling factors cooperatively regulate shank-localized actin bundles remains largely unexplored. Here we demonstrate that FIM5 and PLIM2a/PLIM2b decorate shank-localized actin bundles and that loss of function of PLIM2a and/or PLIM2b suppresses phenotypes associated with fim5 mutants. Specifically, knockout of PLIM2a and/or PLIM2b partially suppresses the disorganized actin bundle and intracellular trafficking phenotype in fim5 pollen tubes. PLIM2a/PLIM2b generates thick but loosely packed actin bundles, whereas FIM5 generates thin but tight actin bundles that tend to be cross-linked into networks in vitro. Furthermore, PLIM2a/PLIM2b and FIM5 compete for binding to actin filaments in vitro, and PLIM2a/PLIM2b decorate disorganized actin bundles in fim5 pollen tubes. These data together suggest that the disorganized actin bundles in fim5 mutants are at least partially due to gain of function of PLIM2a/PLIM2b. Our data suggest that the balance between FIM5 and PLIM2a/PLIM2b is crucial for the normal bundling and organization of shank-localized actin bundles in pollen tubes. The transcription of PLIM2a and PLIM2b is upregulated in fim5 pollen tubes Downregulation of PLIM2a and/or PLIM2b suppresses the defects in fim5 pollen tubes Both FIM5 and PLIM2a/PLIM2b decorate shank-localized actin filaments FIM5 can inhibit the binding of PLIM2a and PLIM2b to actin filaments
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Affiliation(s)
- Ruihui Zhang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiaolu Qu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Meng Zhang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yuxiang Jiang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Anbang Dai
- Ministry of Education Key Laboratory of Protein Sciences, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Wanying Zhao
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Dai Cao
- School of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Yaxian Lan
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Rong Yu
- School of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Hongwei Wang
- Ministry of Education Key Laboratory of Protein Sciences, Tsinghua-Peking Joint Center for Life Sciences, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shanjin Huang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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19
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Le Bail A, Schulmeister S, Perroud PF, Ntefidou M, Rensing SA, Kost B. Analysis of the Localization of Fluorescent PpROP1 and PpROP-GEF4 Fusion Proteins in Moss Protonemata Based on Genomic "Knock-In" and Estradiol-Titratable Expression. FRONTIERS IN PLANT SCIENCE 2019; 10:456. [PMID: 31031790 PMCID: PMC6473103 DOI: 10.3389/fpls.2019.00456] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/26/2019] [Indexed: 05/26/2023]
Abstract
Tip growth of pollen tubes, root hairs, and apical cells of moss protonemata is controlled by ROP (Rho of plants) GTPases, which were shown to accumulate at the apical plasma membrane of these cells. However, most ROP localization patterns reported in the literature are based on fluorescent protein tagging and need to be interpreted with caution, as ROP fusion proteins were generally overexpressed at undefined levels, in many cases without assessing effects on tip growth. ROP-GEFs, important regulators of ROP activity, were also described to accumulate at the apical plasma membrane during tip growth. However, to date only the localization of fluorescent ROP-GEF fusion proteins strongly overexpressed using highly active promoters have been investigated. Here, the intracellular distributions of fluorescent PpROP1 and PpROP-GEF4 fusion proteins expressed at essentially endogenous levels in apical cells of Physcomitrella patens "knock-in" protonemata were analyzed. Whereas PpROP-GEF4 was found to associate with a small apical plasma membrane domain, PpROP1 expression was below the detection limit. Estradiol-titratable expression of a fluorescent PpROP1 fusion protein at the lowest detectable level, at which plant development was only marginally affected, was therefore employed to show that PpROP1 also accumulates at the apical plasma membrane, although within a substantially larger domain. Interestingly, RNA-Seq data indicated that the majority of all genes active in protonemata are expressed at lower levels than PpROP1, suggesting that estradiol-titratable expression may represent an important alternative to "knock-in" based analysis of the intracellular distribution of fluorescent fusion proteins in protonemal cells.
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Affiliation(s)
- Aude Le Bail
- Cell Biology, Department of Biology, Friedrich–Alexander University Erlangen–Nürnberg, Erlangen, Germany
| | - Sylwia Schulmeister
- Cell Biology, Department of Biology, Friedrich–Alexander University Erlangen–Nürnberg, Erlangen, Germany
| | | | - Maria Ntefidou
- Cell Biology, Department of Biology, Friedrich–Alexander University Erlangen–Nürnberg, Erlangen, Germany
| | - Stefan A. Rensing
- Plant Cell Biology, Faculty of Biology, Philipps University of Marburg, Marburg, Germany
| | - Benedikt Kost
- Cell Biology, Department of Biology, Friedrich–Alexander University Erlangen–Nürnberg, Erlangen, Germany
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20
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Qian D, Xiang Y. Actin Cytoskeleton as Actor in Upstream and Downstream of Calcium Signaling in Plant Cells. Int J Mol Sci 2019; 20:ijms20061403. [PMID: 30897737 PMCID: PMC6471457 DOI: 10.3390/ijms20061403] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 03/14/2019] [Accepted: 03/15/2019] [Indexed: 01/04/2023] Open
Abstract
In plant cells, calcium (Ca2+) serves as a versatile intracellular messenger, participating in several fundamental and important biological processes. Recent studies have shown that the actin cytoskeleton is not only an upstream regulator of Ca2+ signaling, but also a downstream regulator. Ca2+ has been shown to regulates actin dynamics and rearrangements via different mechanisms in plants, and on this basis, the upstream signaling encoded within the Ca2+ transient can be decoded. Moreover, actin dynamics have also been proposed to act as an upstream of Ca2+, adjust Ca2+ oscillations, and establish cytosolic Ca2+ ([Ca2+]cyt) gradients in plant cells. In the current review, we focus on the advances in uncovering the relationship between the actin cytoskeleton and calcium in plant cells and summarize our current understanding of this relationship.
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Affiliation(s)
- Dong Qian
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
| | - Yun Xiang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
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21
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Sengupta S, Mangu V, Sanchez L, Bedre R, Joshi R, Rajasekaran K, Baisakh N. An actin-depolymerizing factor from the halophyte smooth cordgrass, Spartina alterniflora (SaADF2), is superior to its rice homolog (OsADF2) in conferring drought and salt tolerance when constitutively overexpressed in rice. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:188-205. [PMID: 29851294 PMCID: PMC6330539 DOI: 10.1111/pbi.12957] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 05/18/2018] [Accepted: 05/25/2018] [Indexed: 05/20/2023]
Abstract
Actin-depolymerizing factors (ADFs) maintain the cellular actin network dynamics by regulating severing and disassembly of actin filaments in response to environmental cues. An ADF isolated from a monocot halophyte, Spartina alterniflora (SaADF2), imparted significantly higher level of drought and salinity tolerance when expressed in rice than its rice homologue OsADF2. SaADF2 differs from OsADF2 by a few amino acid residues, including a substitution in the regulatory phosphorylation site serine-6, which accounted for its weak interaction with OsCDPK6 (calcium-dependent protein kinase), thus resulting in an increased efficacy of SaADF2 and enhanced cellular actin dynamics. SaADF2 overexpression preserved the actin filament organization better in rice protoplasts under desiccation stress. The predicted tertiary structure of SaADF2 showed a longer F-loop than OsADF2 that could have contributed to higher actin-binding affinity and rapid F-actin depolymerization in vitro by SaADF2. Rice transgenics constitutively overexpressing SaADF2 (SaADF2-OE) showed better growth, relative water content, and photosynthetic and agronomic yield under drought conditions than wild-type (WT) and OsADF2 overexpressers (OsADF2-OE). SaADF2-OE preserved intact grana structure after prolonged drought stress, whereas WT and OsADF2-OE presented highly damaged and disorganized grana stacking. The possible role of ADF2 in transactivation was hypothesized from the comparative transcriptome analyses, which showed significant differential expression of stress-related genes including interacting partners of ADF2 in overexpressers. Identification of a complex, differential interactome decorating or regulating stress-modulated cytoskeleton driven by ADF isoforms will lead us to key pathways that could be potential target for genome engineering to improve abiotic stress tolerance in agricultural crops.
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Affiliation(s)
- Sonali Sengupta
- School of PlantEnvironmental and Soil SciencesLouisiana State University Agricultural CenterBaton RougeLAUSA
| | - Venkata Mangu
- School of PlantEnvironmental and Soil SciencesLouisiana State University Agricultural CenterBaton RougeLAUSA
- Present address:
Department of BiochemistrySchool of Dental MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
| | - Luis Sanchez
- School of PlantEnvironmental and Soil SciencesLouisiana State University Agricultural CenterBaton RougeLAUSA
- Present address:
Escuela Superior Politécnica del LitoralCentro de Investigaciones Biotecnológicas del EcuadorGuayaquilEcuador
| | - Renesh Bedre
- School of PlantEnvironmental and Soil SciencesLouisiana State University Agricultural CenterBaton RougeLAUSA
- Present address:
Texas A&M AgriLife Research and Extension CenterWeslacoTXUSA
| | - Rohit Joshi
- School of PlantEnvironmental and Soil SciencesLouisiana State University Agricultural CenterBaton RougeLAUSA
- Present address:
School of Life SciencesJawaharlal Nehru UniversityNew DelhiIndia
| | | | - Niranjan Baisakh
- School of PlantEnvironmental and Soil SciencesLouisiana State University Agricultural CenterBaton RougeLAUSA
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22
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Sengupta S, Rajasekaran K, Baisakh N. Natural and targeted isovariants of the rice actin depolymerizing factor 2 can alter its functional and regulatory binding properties. Biochem Biophys Res Commun 2018; 503:1516-1523. [PMID: 30031604 DOI: 10.1016/j.bbrc.2018.07.073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 07/16/2018] [Indexed: 10/28/2022]
Abstract
Actin depolymerizing factors (ADFs) are ubiquitous actin-binding proteins that play essential roles in maintaining cellular actin dynamics by depolymerizing/severing F-actin. Plant ADF isoforms show functional divergence via differential biochemical and cellular properties. We have shown previously that ADF2 of rice (OsADF2) and smooth cordgrass (SaADF2) displayed contrasting biochemical properties and stress response in planta. As a proof-of-concept that amino acid variances contribute to such functional difference, single amino acid mutants of OsADF2 were generated based on its sequence differences with SaADF2. Biochemical studies showed that the single-site amino acid mutations altered actin binding, depolymerizing, and severing properties of OsADF2. Phosphosensitive mutations, such as serine-6>threonine, changed the regulatory phosphorylation efficiency of ADF2 variants. The N-terminal mutations had greater effect on the phosphorylation pattern of OsADF2, whereas C-terminal mutations affected actin binding and severing. The presence of introduced mutations in isovariants of monocot ADF suggests that these residues are significant control points regulating their functional divergence, including abiotic stress response.
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Affiliation(s)
- Sonali Sengupta
- School of Plant, Environmental and Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, USA
| | | | - Niranjan Baisakh
- School of Plant, Environmental and Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, USA.
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23
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Wu SZ, Bezanilla M. Actin and microtubule cross talk mediates persistent polarized growth. J Cell Biol 2018; 217:3531-3544. [PMID: 30061106 PMCID: PMC6168251 DOI: 10.1083/jcb.201802039] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/08/2018] [Accepted: 07/10/2018] [Indexed: 11/25/2022] Open
Abstract
How the actin and microtubule cytoskeletons work together during diverse cellular functions is unclear. Wu et al. describe an apical actin pool in plant cells organized by a microtubule template at the site of polarized growth. Disconnecting the two cytoskeletons by removing class VIII myosins alters both cytoskeletal structures and impairs polarized growth. Coordination between actin and microtubules is important for numerous cellular processes in diverse eukaryotes. In plants, tip-growing cells require actin for cell expansion and microtubules for orientation of cell expansion, but how the two cytoskeletons are linked is an open question. In tip-growing cells of the moss Physcomitrella patens, we show that an actin cluster near the cell apex dictates the direction of rapid cell expansion. Formation of this structure depends on the convergence of microtubules near the cell tip. We discovered that microtubule convergence requires class VIII myosin function, and actin is necessary for myosin VIII–mediated focusing of microtubules. The loss of myosin VIII function affects both networks, indicating functional connections among the three cytoskeletal components. Our data suggest that microtubules direct localization of formins, actin nucleation factors, that generate actin filaments further focusing microtubules, thereby establishing a positive feedback loop ensuring that actin polymerization and cell expansion occur at a defined site resulting in persistent polarized growth.
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Affiliation(s)
- Shu-Zon Wu
- Department of Biological Sciences, Dartmouth College, Hanover, NH
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Ding X, Pervere LM, Bascom C, Bibeau JP, Khurana S, Butt AM, Orr RG, Flaherty PJ, Bezanilla M, Vidali L. Conditional genetic screen in Physcomitrella patens reveals a novel microtubule depolymerizing-end-tracking protein. PLoS Genet 2018; 14:e1007221. [PMID: 29746462 PMCID: PMC5944918 DOI: 10.1371/journal.pgen.1007221] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 01/24/2018] [Indexed: 11/19/2022] Open
Abstract
Our ability to identify genes that participate in cell growth and division is limited because their loss often leads to lethality. A solution to this is to isolate conditional mutants where the phenotype is visible under restrictive conditions. Here, we capitalize on the haploid growth-phase of the moss Physcomitrella patens to identify conditional loss-of-growth (CLoG) mutants with impaired growth at high temperature. We used whole-genome sequencing of pooled segregants to pinpoint the lesion of one of these mutants (clog1) and validated the identified mutation by rescuing the conditional phenotype by homologous recombination. We found that CLoG1 is a novel and ancient gene conserved in plants. At the restrictive temperature, clog1 plants have smaller cells but can complete cell division, indicating an important role of CLoG1 in cell growth, but not an essential role in cell division. Fluorescent protein fusions of CLoG1 indicate it is localized to microtubules with a bias towards depolymerizing microtubule ends. Silencing CLoG1 decreases microtubule dynamics, suggesting that CLoG1 plays a critical role in regulating microtubule dynamics. By discovering a novel gene critical for plant growth, our work demonstrates that P. patens is an excellent genetic system to study genes with a fundamental role in plant cell growth.
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Affiliation(s)
- Xinxin Ding
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA
- Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA
| | - Leah M. Pervere
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA
- Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA
| | - Carl Bascom
- Plant Biology Graduate Program, University of Massachusetts, Amherst, MA
- Department of Biological Sciences, Dartmouth College, Hanover, NH
| | - Jeffrey P. Bibeau
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA
| | - Sakshi Khurana
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA
| | - Allison M. Butt
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA
| | - Robert G. Orr
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA
| | - Patrick J. Flaherty
- Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA
- Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA
| | | | - Luis Vidali
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA
- Bioinformatics and Computational Biology Program, Worcester Polytechnic Institute, Worcester, MA
- * E-mail:
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25
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Simultaneous imaging and functional studies reveal a tight correlation between calcium and actin networks. Proc Natl Acad Sci U S A 2018; 115:E2869-E2878. [PMID: 29507239 DOI: 10.1073/pnas.1711037115] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Tip-growing cells elongate in a highly polarized manner via focused secretion of flexible cell-wall material. Calcium has been implicated as a vital factor in regulating the deposition of cell-wall material. However, deciphering the molecular and mechanistic calcium targets in vivo has remained challenging. Here, we investigated intracellular calcium dynamics in the moss Physcomitrella patens, which provides a system with an abundant source of genetically identical tip-growing cells, excellent cytology, and a large molecular genetic tool kit. To visualize calcium we used a genetically encoded cytosolic FRET probe, revealing a fluctuating tipward gradient with a complex oscillatory profile. Wavelet analysis coupled with a signal-sifting algorithm enabled the quantitative comparison of the calcium behavior in cells where growth was inhibited mechanically, pharmacologically, or genetically. We found that cells with suppressed growth have calcium oscillatory profiles with longer frequencies, suggesting that there is a feedback between the calcium gradient and growth. To investigate the mechanistic basis for this feedback we simultaneously imaged cytosolic calcium and actin, which has been shown to be essential for tip growth. We found that high cytosolic calcium promotes disassembly of a tip-focused actin spot, while low calcium promotes assembly. In support of this, abolishing the calcium gradient resulted in dramatic actin accumulation at the tip. Together these data demonstrate that tipward calcium is quantitatively linked to actin accumulation in vivo and that the moss P. patens provides a powerful system to uncover mechanistic links between calcium, actin, and growth.
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Grimplet J, Ibáñez S, Baroja E, Tello J, Ibáñez J. Phenotypic, Hormonal, and Genomic Variation Among Vitis vinifera Clones With Different Cluster Compactness and Reproductive Performance. FRONTIERS IN PLANT SCIENCE 2018; 9:1917. [PMID: 30666262 PMCID: PMC6330345 DOI: 10.3389/fpls.2018.01917] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 12/10/2018] [Indexed: 05/09/2023]
Abstract
Previous studies showed that the number of berries is a major component of the compactness level of the grapevine clusters. Variation in number of fruits is regulated by events occurring in the fruitset, but also before during the flower formation and pollination, through factors like the initial number of flowers or the gametic viability. Therefore, the identification of the genetic bases of this variation would provide an invaluable knowledge of the grapevine reproductive development and useful tools for managing yield and cluster compactness. We performed the phenotyping of four clones (two compact and two loose clones) of the Tempranillo cultivar with reproducible different levels of cluster compactness over seasons. Measures of reproductive performance included flower number per inflorescence, berry number per cluster, fruitset, coulure, and millerandage indices. Besides, their levels of several hormones during the inflorescence and flower development were determined, and their transcriptomes were evaluated at critical time points (just before the start and at the end of flowering). For some key reproductive traits, like number of berries per cluster and number of seeds per berry, clones bearing loose clusters showed differences with the compact clones and also differed from each other, indicating that each one follows different paths to produce loose clusters. Variation between clones was observed for abscisic acid and gibberellins levels at particular development stages, and differences in GAs could be related to phenotypic differences. Likewise, various changes between clones were found at the transcriptomic level, mostly just before the start of flowering. Several of the differentially expressed genes between one of the loose clones and the compact clones are known to be over-expressed in pollen, and many of them were related to cell wall modification processes or to the phenylpropanoids metabolism. We also found polymorphisms between clones in candidate genes that could be directly involved in the variation of the compactness level.
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Jiang Y, Wang J, Xie Y, Chen N, Huang S. ADF10 shapes the overall organization of apical actin filaments by promoting their turnover and ordering in pollen tubes. J Cell Sci 2017; 130:3988-4001. [PMID: 29061882 DOI: 10.1242/jcs.207738] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Accepted: 10/09/2017] [Indexed: 12/26/2022] Open
Abstract
Here, we show that Arabidopsis ADF10 plays an important role in shaping the overall organization of apical actin filaments by promoting their turnover and ordering. ADF10 severs and depolymerizes actin filaments in vitro and is distributed throughout the entire pollen tube. In adf10 mutants, severing and monomer dissociation events for apical actin filaments are reduced, and the apical actin structure extends further toward the tube base than in wild-type tubes. In particular, the percentage of apical actin filaments that form large angles to the tube growth axis is much higher in adf10 pollen tubes, and the actin filaments are more randomly distributed, implying that ADF10 promotes their ordering. Consistent with the role of apical actin filaments in physically restricting the movement of vesicles, the region in which apical vesicles accumulate is enlarged at the tip of adf10 pollen tubes. Both tipward and backward movements of small vesicles are altered within the growth domain of adf10 pollen tubes. Thus, our study suggests that ADF10 shapes the organization of apical actin filaments to regulate vesicle trafficking and pollen tube growth.
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Affiliation(s)
- Yuxiang Jiang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Juan Wang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yurong Xie
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Naizhi Chen
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Shanjin Huang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
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28
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Zhu J, Nan Q, Qin T, Qian D, Mao T, Yuan S, Wu X, Niu Y, Bai Q, An L, Xiang Y. Higher-Ordered Actin Structures Remodeled by Arabidopsis ACTIN-DEPOLYMERIZING FACTOR5 Are Important for Pollen Germination and Pollen Tube Growth. MOLECULAR PLANT 2017; 10:1065-1081. [PMID: 28606871 DOI: 10.1016/j.molp.2017.06.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 06/02/2017] [Accepted: 06/05/2017] [Indexed: 06/07/2023]
Abstract
Dynamics of the actin cytoskeleton are essential for pollen germination and pollen tube growth. ACTIN-DEPOLYMERIZING FACTORs (ADFs) typically contribute to actin turnover by severing/depolymerizing actin filaments. Recently, we demonstrated that Arabidopsis subclass III ADFs (ADF5 and ADF9) evolved F-actin-bundling function from conserved F-actin-depolymerizing function. However, little is known about the physiological function, the evolutional significance, and the actin-bundling mechanism of these neofunctionalized ADFs. Here, we report that loss of ADF5 function caused delayed pollen germination, retarded pollen tube growth, and increased sensitive to latrunculin B (LatB) treatment by affecting the generation and maintenance of actin bundles. Examination of actin filament dynamics in living cells revealed that the bundling frequency was significantly decreased in adf5 pollen tubes, consistent with its biochemical functions. Further biochemical and genetic complementation analyses demonstrated that both the N- and C-terminal actin-binding domains of ADF5 are required for its physiological and biochemical functions. Interestingly, while both are atypical actin-bundling ADFs, ADF5, but not ADF9, plays an important role in mature pollen physiological activities. Taken together, our results suggest that ADF5 has evolved the function of bundling actin filaments and plays an important role in the formation, organization, and maintenance of actin bundles during pollen germination and pollen tube growth.
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Affiliation(s)
- Jingen Zhu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Qiong Nan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Tao Qin
- State Key Laboratory of Plant Physiology and Biochemistry, Department of Plant Sciences, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Dong Qian
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Tonglin Mao
- State Key Laboratory of Plant Physiology and Biochemistry, Department of Plant Sciences, College of Biological Sciences, China Agricultural University, Beijing 100193, China
| | - Shunjie Yuan
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Xiaorong Wu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yue Niu
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Qifeng Bai
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Lizhe An
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yun Xiang
- MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China.
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Takáč T, Šamajová O, Pechan T, Luptovčiak I, Šamaj J. Feedback Microtubule Control and Microtubule-Actin Cross-talk in Arabidopsis Revealed by Integrative Proteomic and Cell Biology Analysis of KATANIN 1 Mutants. Mol Cell Proteomics 2017; 16:1591-1609. [PMID: 28706004 DOI: 10.1074/mcp.m117.068015] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 06/06/2017] [Indexed: 12/20/2022] Open
Abstract
Microtubule organization and dynamics are critical for key developmental processes such as cell division, elongation, and morphogenesis. Microtubule severing is an essential regulator of microtubules and is exclusively executed by KATANIN 1 in Arabidopsis In this study, we comparatively studied the proteome-wide effects in two KATANIN 1 mutants. Thus, shotgun proteomic analysis of roots and aerial parts of single nucleotide mutant fra2 and T-DNA insertion mutant ktn1-2 was carried out. We have detected 42 proteins differentially abundant in both fra2 and ktn1-2 KATANIN 1 dysfunction altered the abundance of proteins involved in development, metabolism, and stress responses. The differential regulation of tubulins and microtubule-destabilizing protein MDP25 implied a feedback microtubule control in KATANIN 1 mutants. Furthermore, deregulation of profilin 1, actin-depolymerizing factor 3, and actin 7 was observed. These findings were confirmed by immunoblotting analysis of actin and by microscopic observation of actin filaments using fluorescently labeled phalloidin. Results obtained by quantitative RT-PCR analysis revealed that changed protein abundances were not a consequence of altered expression levels of corresponding genes in the mutants. In conclusion, we show that abundances of several cytoskeletal proteins as well as organization of microtubules and the actin cytoskeleton are amended in accordance with defective microtubule severing.
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Affiliation(s)
- Tomáš Takáč
- From the ‡Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Olga Šamajová
- From the ‡Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Tibor Pechan
- §Institute for Genomics, Biocomputing and Biotechnology, Mississippi Agricultural and Forestry Experiment Station, Mississippi State University, Starkville, Mississippi 39759
| | - Ivan Luptovčiak
- From the ‡Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic
| | - Jozef Šamaj
- From the ‡Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic;
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30
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Inada N. Plant actin depolymerizing factor: actin microfilament disassembly and more. JOURNAL OF PLANT RESEARCH 2017; 130:227-238. [PMID: 28044231 PMCID: PMC5897475 DOI: 10.1007/s10265-016-0899-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 11/14/2016] [Indexed: 05/19/2023]
Abstract
ACTIN DEPOLYMERIZING FACTOR (ADF) is a conserved protein among eukaryotes. The main function of ADF is the severing and depolymerizing filamentous actin (F-actin), thus regulating F-actin organization and dynamics and contributing to growth and development of the organisms. Mammalian genomes contain only a few ADF genes, whereas angiosperm plants have acquired an expanding number of ADFs, resulting in the differentiation of physiological functions. Recent studies have revealed functions of ADFs in plant growth and development, and various abiotic and biotic stress responses. In biotic stress responses, ADFs are involved in both susceptibility and resistance, depending on the pathogens. Furthermore, recent studies have highlighted a new role of ADF in the nucleus, possibly in the regulation of gene expression. In this review, I will summarize the current status of plant ADF research and discuss future research directions.
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Affiliation(s)
- Noriko Inada
- The Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma-shi, Nara, 630-0192, Japan.
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31
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Tang LP, Li XM, Dong YX, Zhang XS, Su YH. Microfilament Depolymerization Is a Pre-requisite for Stem Cell Formation During In vitro Shoot Regeneration in Arabidopsis. FRONTIERS IN PLANT SCIENCE 2017; 8:158. [PMID: 28261231 PMCID: PMC5306138 DOI: 10.3389/fpls.2017.00158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Accepted: 01/25/2017] [Indexed: 05/23/2023]
Abstract
De novo shoot regeneration is widely used in fundamental studies and agricultural applications. Actin microfilaments are involved in many aspects of plant cell division, cell morphogenesis and cell signal transduction. However, the function of actin microfilaments during de novo shoot regeneration is poorly understood. Here, we investigated the organization of actin microfilaments during this process and found that stem cell formation was associated with microfilament depolymerization. Furthermore, inhibition of microfilament depolymerization by phalloidin treatment or downregulation of actin depolymerizing factors (ADFs) restrained stem cell initiation and shoot regeneration. Inhibition of ADF expression affected the architecture of microfilaments during stem cell formation, and the polar transport and distribution of auxin were also disrupted. Together, our results demonstrate that organization of the microfilament cytoskeleton play important roles in stem cell formation and shoot meristem induction during shoot regeneration.
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Affiliation(s)
- Li Ping Tang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural UniversityTaian, China
| | - Xiao Ming Li
- Shandong Provincial Key Laboratory of Agricultural Microbiology, College of Plant Protection, Shandong Agricultural UniversityTaian, China
| | - Yu Xiu Dong
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural UniversityTaian, China
| | - Xian Sheng Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural UniversityTaian, China
| | - Ying Hua Su
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural UniversityTaian, China
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Abstract
Protein phosphorylation was repeatedly shown to be the most dynamic post-translational modification mediated by a huge orchestra of protein kinases and phosphatases. Upon landing on a stigma, pollen grain dehydration and activation are accompanied by changes in protein phosphorylation together with the translation activation of stored mRNAs. To enable studies of the total phosphoproteome, it is usually necessary to apply various enrichment techniques. In this chapter, one of these protocols that worked previously well on tobacco mature pollen is presented in more detail. The method comprises of three basic steps: (1) picking flowers from the flowering tobacco plants (Nicotiana tabacum cv. Samsun), and collection of the shed pollen grains; (2) extraction of total proteins by TCA/acetone; (3) phosphoprotein enrichment by MOAC with aluminum hydroxide matrix. Taken together this protocol describes how to isolate phosphoproteins out of tobacco mature pollen.
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Affiliation(s)
- Jan Fíla
- Laboratory of Pollen Biology, Institute of Experimental Botany, AS CR, v.v.i., Rozvojová 263, 165 02, Prague 6, Lysolaje, Czech Republic
| | - David Honys
- Laboratory of Pollen Biology, Institute of Experimental Botany, AS CR, v.v.i., Rozvojová 263, 165 02, Prague 6, Lysolaje, Czech Republic.
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Khatun K, Robin AHK, Park JI, Kim CK, Lim KB, Kim MB, Lee DJ, Nou IS, Chung MY. Genome-Wide Identification, Characterization and Expression Profiling of ADF Family Genes in Solanum lycopersicum L. Genes (Basel) 2016; 7:E79. [PMID: 27690110 PMCID: PMC5083918 DOI: 10.3390/genes7100079] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 09/12/2016] [Accepted: 09/22/2016] [Indexed: 12/15/2022] Open
Abstract
The actin depolymerizing factor (ADF) proteins have growth, development, defense-related and growth regulatory functions in plants. The present study used genome-wide analysis to investigate ADF family genes in tomato. Eleven tomato ADF genes were identified and differential expression patterns were found in different organs. SlADF6 was preferentially expressed in roots, suggesting its function in root development. SlADF1, SlADF3 and SlADF10 were predominately expressed in the flowers compared to the other organs and specifically in the stamen compared to other flower parts, indicating their potential roles in pollen development. The comparatively higher expression of SlADF3 and SlADF11 at early fruit developmental stages might implicate them in determining final fruit size. SlADF5 and SlADF8 had relatively higher levels of expression five days after the breaker stage of fruit development, suggesting their possible role in fruit ripening. Notably, six genes were induced by cold and heat, seven by drought, five by NaCl, and four each by abscisic acid (ABA), jasmonic acid (JA) and wounding treatments. The differential expression patterns of the SlADF genes under different types of stresses suggested their function in stress tolerance in tomato plants. Our results will be helpful for the functional characterization of ADF genes during organ and fruit development of tomato under different stresses.
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Affiliation(s)
- Khadiza Khatun
- Department of Agricultural Industry Economy and Education, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
| | - Arif Hasan Khan Robin
- Department of Horticulture, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
| | - Jong-In Park
- Department of Horticulture, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
| | - Chang Kil Kim
- Department of Horticultural Science, Kyungpook National University, Daegu 702-701, Korea.
| | - Ki-Byung Lim
- Department of Horticultural Science, Kyungpook National University, Daegu 702-701, Korea.
| | - Min-Bae Kim
- Department of Agricultural Industry Economy and Education, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
- Department of Agricultural Education, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
| | - Do-Jin Lee
- Department of Agricultural Industry Economy and Education, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
- Department of Agricultural Education, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
| | - Ill Sup Nou
- Department of Horticulture, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
| | - Mi-Young Chung
- Department of Agricultural Industry Economy and Education, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
- Department of Agricultural Education, Sunchon National University, 413 Jungangno, Suncheon, Jeonnam 540-950, Korea.
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Liu B, Liu X, Liu Y, Xue S, Cai Y, Yang S, Dong M, Zhang Y, Liu H, Zhao B, Qi C, Zhu N, Ren H. The Infection of Cucumber ( Cucumis sativus L.) Roots by Meloidogyne incognita Alters the Expression of Actin-Depolymerizing Factor ( ADF) Genes, Particularly in Association with Giant Cell Formation. FRONTIERS IN PLANT SCIENCE 2016; 7:1393. [PMID: 27695469 PMCID: PMC5025442 DOI: 10.3389/fpls.2016.01393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 09/01/2016] [Indexed: 05/27/2023]
Abstract
Cucumber (Cucumis sativus L.) is threatened by substantial yield losses due to the south root-knot nematode (Meloidogyne incognita). However, understanding of the molecular mechanisms underlying the process of nematode infection is still limited. In this study, we found that M. incognita infection affected the structure of cells in cucumber roots and treatment of the cytoskeleton inhibitor (cytochalasin D) reduced root-knot nematode (RKN) parasitism. It is known that Actin-Depolymerizing Factor (ADF) affects cell structure, as well as the organization of the cytoskeleton. To address the hypothesis that nematode-induced abnormal cell structures and cytoskeletal rearrangements might be mediated by the ADF genes, we identified and characterized eight cucumber ADF (CsADF) genes. Phylogenetic analysis showed that the cucumber ADF gene family is grouped into four ancient subclasses. Expression analysis revealed that CsADF1, CsADF2-1, CsADF2-2, CsADF2-3 (Subclass I), and CsADF6 (Subclass III) have higher transcript levels than CsADF7-1, CsADF7-2 (Subclass II genes), and CsADF5 (Subclass IV) in roots. Members of subclass I genes (CsADF1, CsADF2-1, CsADF2-2, and CsADF2-3), with the exception of CsADF2-1, exhibited a induction of expression in roots 14 days after their inoculation (DAI) with nematodes. However, the expression of subclass II genes (CsADF7-1 and CsADF7-2) showed no significant change after inoculation. The transcript levels of CsADF6 (Subclass III) showed a specific induction at 21 DAI, while CsADF5 (Subclass IV) was weakly expressed in roots, but was strongly up-regulated as early as 7 DAI. In addition, treatment of roots with cytochalasin D caused an approximately 2-fold down-regulation of the CsADF genes in the treated plants. These results suggest that CsADF gene mediated actin dynamics are associated with structural changes in roots as a consequence of M. incognita infection.
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Affiliation(s)
- Bin Liu
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Xingwang Liu
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Ying Liu
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Shudan Xue
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Yanling Cai
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Sen Yang
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Mingming Dong
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Yaqi Zhang
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Huiling Liu
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Binyu Zhao
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
| | - Changhong Qi
- Changping Agricultural Technology Service CenterBeijing, China
| | - Ning Zhu
- Changping Agricultural Technology Service CenterBeijing, China
| | - Huazhong Ren
- Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops of Beijing, Department of Vegetable Science, College of Horticulture, China Agricultural UniversityBeijing, China
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Burkart GM, Baskin TI, Bezanilla M. A family of ROP proteins that suppresses actin dynamics, and is essential for polarized growth and cell adhesion. J Cell Sci 2015; 128:2553-64. [PMID: 26045445 DOI: 10.1242/jcs.172445] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 05/31/2015] [Indexed: 01/22/2023] Open
Abstract
In plants, the ROP family of small GTPases has been implicated in the polarized growth of tip-growing cells, such as root hairs and pollen tubes; however, most of the data derive from overexpressing ROP genes or constitutively active and dominant-negative isoforms, whereas confirmation by using loss-of-function studies has generally been lacking. Here, in the model moss Physcomitrella patens, we study ROP signaling during tip growth by using a loss-of-function approach based on RNA interference (RNAi) to silence the entire moss ROP family. We find that plants with reduced expression of ROP genes, in addition to failing to initiate tip growth, have perturbed cell wall staining, reduced cell adhesion and have increased actin-filament dynamics. Although plants subjected to RNAi against the ROP family also have reduced microtubule dynamics, this reduction is not specific to loss of ROP genes, as it occurs when actin function is compromised chemically or genetically. Our data suggest that ROP proteins polarize the actin cytoskeleton by suppressing actin-filament dynamics, leading to an increase in actin filaments at the site of polarized secretion.
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Affiliation(s)
- Graham M Burkart
- Department of Biology, University of Massachusetts-Amherst, 611 N. Pleasant Street, Amherst, MA 01003, USA Plant Biology Graduate Program, University of Massachusetts-Amherst, 611 N. Pleasant Street, Amherst, MA 01003, USA
| | - Tobias I Baskin
- Department of Biology, University of Massachusetts-Amherst, 611 N. Pleasant Street, Amherst, MA 01003, USA
| | - Magdalena Bezanilla
- Department of Biology, University of Massachusetts-Amherst, 611 N. Pleasant Street, Amherst, MA 01003, USA
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Miki T, Nishina M, Goshima G. RNAi screening identifies the armadillo repeat-containing kinesins responsible for microtubule-dependent nuclear positioning in Physcomitrella patens. PLANT & CELL PHYSIOLOGY 2015; 56:737-49. [PMID: 25588389 DOI: 10.1093/pcp/pcv002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 01/05/2015] [Indexed: 05/22/2023]
Abstract
Proper positioning of the nucleus is critical for the functioning of various cells. Actin and myosin have been shown to be crucial for the localization of the nucleus in plant cells, whereas microtubule (MT)-based mechanisms are commonly utilized in animal and fungal cells. In this study, we combined live cell microscopy with RNA interference (RNAi) screening or drug treatment and showed that MTs and a plant-specific motor protein, armadillo repeat-containing kinesin (kinesin-ARK), are required for nuclear positioning in the moss Physcomitrella patens. In tip-growing protonemal apical cells, the nucleus was translocated to the center of the cell after cell division in an MT-dependent manner. When kinesin-ARKs were knocked down using RNAi, the initial movement of the nucleus towards the center took place normally; however, before reaching the center, the nucleus was moved back to the basal edge of the cell. In intact (control) cells, MT bundles that are associated with kinesin-ARKs were frequently observed around the moving nucleus. In contrast, such MT bundles were not identified after kinesin-ARK down-regulation. An in vitro MT gliding assay showed that kinesin-ARK is a plus-end-directed motor protein. These results indicate that MTs and the MT-based motor drive nuclear migration in the moss cells, thus showing a conservation of the mechanism underlying nuclear localization among plant, animal and fungal cells.
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Affiliation(s)
- Tomohiro Miki
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Momoko Nishina
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan
| | - Gohta Goshima
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602 Japan Marine Biological Laboratory, Woods Hole, MA 02543, USA
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Wang WQ, Liu SJ, Song SQ, Møller IM. Proteomics of seed development, desiccation tolerance, germination and vigor. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2015; 86:1-15. [PMID: 25461695 DOI: 10.1016/j.plaphy.2014.11.003] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 11/03/2014] [Indexed: 05/19/2023]
Abstract
Proteomics, the large-scale study of the total complement of proteins in a given sample, has been applied to all aspects of seed biology mainly using model species such as Arabidopsis or important agricultural crops such as corn and rice. Proteins extracted from the sample have typically been separated and quantified by 2-dimensional polyacrylamide gel electrophoresis followed by liquid chromatography and mass spectrometry to identify the proteins in the gel spots. In this way, qualitative and quantitative changes in the proteome during seed development, desiccation tolerance, germination, dormancy release, vigor alteration and responses to environmental factors have all been studied. Many proteins or biological processes potentially important for each seed process have been highlighted by these studies, which greatly expands our knowledge of seed biology. Proteins that have been identified to be particularly important for at least two of the seed processes are involved in detoxification of reactive oxygen species, the cytoskeleton, glycolysis, protein biosynthesis, post-translational modifications, methionine metabolism, and late embryogenesis-abundant (LEA) proteins. It will be useful for molecular biologists and molecular plant breeders to identify and study genes encoding particularly interesting target proteins with the aim to improve the yield, stress tolerance or other critical properties of our crop species.
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Affiliation(s)
- Wei-Qing Wang
- Key Laboratory of Plant Resources and Beijing Botanical Garden, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China
| | - Shu-Jun Liu
- Key Laboratory of Plant Resources and Beijing Botanical Garden, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China
| | - Song-Quan Song
- Key Laboratory of Plant Resources and Beijing Botanical Garden, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China.
| | - Ian Max Møller
- Department of Molecular Biology and Genetics, Aarhus University, Flakkebjerg, DK-4200 Slagelse, Denmark.
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38
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Deng G, Liu LJ, Zhong XY, Lao CY, Wang HY, Wang B, Zhu C, Shah F, Peng DX. Comparative proteome analysis of the response of ramie under N, P and K deficiency. PLANTA 2014; 239:1175-86. [PMID: 24573224 DOI: 10.1007/s00425-014-2040-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 02/03/2014] [Indexed: 05/08/2023]
Abstract
Ramie is an important natural fiber. There has been little research on the molecular mechanisms of ramie related to the absorption, utilization and metabolism of nitrogen (N), phosphorus (P) and potassium (K). One approach to reveal the mechanisms of N, P and K (NPK) utilization and metabolism in ramie is comparative proteome analysis. The differentially expressed proteins in the leaves of ramie were analyzed by proteome analysis after 6 days of N- and K-deficient treatments and 3 days of P-deficient treatment using MALDI-TOF/TOF mass spectrometry and 32, 27 and 51 differential proteins were obtained, respectively. These proteins were involved in photosynthesis, protein destination and storage, energy metabolism, primary metabolism, disease/defense, signal transduction, cell structure, transcription, secondary metabolism and protein synthesis. Ramie responded to NPK stress by enhancing secondary metabolism and reducing photosynthesis and energy metabolism to increase endurance. Specifically, ramie adapted to NPK deficiency by increasing signal transduction pathways, enhancing the connection between glycolysis and photosynthesis, promoting the intracellular flow of carbon and N; promoting the synthesis cysteine and related hormones and upregulating actin protein to promote growth of the root system. The experimental results provide important information for further study on the high-efficiency NPK utilization mechanism of ramie.
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Affiliation(s)
- Gang Deng
- MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
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39
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Gilbert MK, Kim HJ, Tang Y, Naoumkina M, Fang DD. Comparative transcriptome analysis of short fiber mutants Ligon-lintless 1 and 2 reveals common mechanisms pertinent to fiber elongation in cotton (Gossypium hirsutum L.). PLoS One 2014; 9:e95554. [PMID: 24748059 PMCID: PMC3991655 DOI: 10.1371/journal.pone.0095554] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 03/27/2014] [Indexed: 02/03/2023] Open
Abstract
Understanding the molecular processes affecting cotton (Gossypium hirsutum) fiber development is important for developing tools aimed at improving fiber quality. Short fiber cotton mutants Ligon-lintless 1 (Li1) and Ligon-lintless 2 (Li2) are naturally occurring, monogenic mutations residing on different chromosomes. Both mutations cause early cessation in fiber elongation. These two mutants serve as excellent model systems to elucidate molecular mechanisms relevant to fiber length development. Previous studies of these mutants using transcriptome analysis by our laboratory and others had been limited by the fact that very large numbers of genes showed altered expression patterns in the mutants, making a targeted analysis difficult or impossible. In this research, a comparative microarray analysis was conducted using these two short fiber mutants and their near isogenic wild type (WT) grown under both field and greenhouse environments in order to identify key genes or metabolic pathways common to fiber elongation. Analyses of three transcriptome profiles obtained from different growth conditions and mutant types showed that most differentially expressed genes (DEGs) were affected by growth conditions. Under field conditions, short fiber mutants commanded higher expression of genes related to energy production, manifested by the increasing of mitochondrial electron transport activity or responding to reactive oxygen species when compared to the WT. Eighty-eight DEGs were identified to have altered expression patterns common to both short fiber mutants regardless of growth conditions. Enrichment, pathway and expression analyses suggested that these 88 genes were likely involved in fiber elongation without being affected by growth conditions.
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Affiliation(s)
- Matthew K. Gilbert
- Cotton Fiber Bioscience Research Unit, USDA-ARS, Southern Regional Research Center, New Orleans, Louisiana, United States of America
| | - Hee Jin Kim
- Cotton Fiber Bioscience Research Unit, USDA-ARS, Southern Regional Research Center, New Orleans, Louisiana, United States of America
| | - Yuhong Tang
- The Samuel Roberts Noble Foundation, Genomics Core Facility, Ardmore, Oklahoma, United States of America
| | - Marina Naoumkina
- Cotton Fiber Bioscience Research Unit, USDA-ARS, Southern Regional Research Center, New Orleans, Louisiana, United States of America
| | - David D. Fang
- Cotton Fiber Bioscience Research Unit, USDA-ARS, Southern Regional Research Center, New Orleans, Louisiana, United States of America
- * E-mail:
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Fu Y, Duan X, Tang C, Li X, Voegele RT, Wang X, Wei G, Kang Z. TaADF7, an actin-depolymerizing factor, contributes to wheat resistance against Puccinia striiformis f. sp. tritici. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 78:16-30. [PMID: 24635700 DOI: 10.1111/tpj.12457] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Revised: 12/10/2013] [Accepted: 01/09/2014] [Indexed: 05/21/2023]
Abstract
The actin cytoskeleton is involved in plant defense responses; however, the role of the actin-depolymerizing factor (ADF) family, which regulates actin cytoskeletal dynamics, in plant disease resistance, is largely unknown. Here, we characterized a wheat (Triticum aestivum) ADF gene, TaADF7, with three copies located on chromosomes 1A, 1B, and 1D, respectively. All three copies encoded the same protein, although there were variations in 19 nucleotide positions in the open reading frame. Transcriptional expression of the three TaADF7 copies were all sharply elevated in response to avirulent Puccinia striiformis f. sp. tritici (Pst) infection, with similar expression patterns. TaADF7 regulated the actin cytoskeletal dynamics by targeting the actin cytoskeleton to execute actin binding/severing activities. When the TaADF7 copies were all silenced by virus-induced gene silencing, the growth of Pst hypha increased and sporadic urediniospores were observed, as compared with control plants, upon inoculation with avirulent Pst. In addition, the accumulation of reactive oxygen species (ROS) and the hypersensitive response (HR) were greatly weakened, whereas cytochalasin B partially rescued the HR in TaADF7 knock-down plants. Together, these findings suggest that TaADF7 is likely to contribute to wheat resistance against Pst infection by modulating the actin cytoskeletal dynamics to influence ROS accumulation and the HR.
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Affiliation(s)
- Yanping Fu
- State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China
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41
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Zepeda I, Sánchez-López R, Kunkel JG, Bañuelos LA, Hernández-Barrera A, Sánchez F, Quinto C, Cárdenas L. Visualization of highly dynamic F-actin plus ends in growing phaseolus vulgaris root hair cells and their responses to Rhizobium etli nod factors. PLANT & CELL PHYSIOLOGY 2014; 55:580-592. [PMID: 24399235 DOI: 10.1093/pcp/pct202] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Legume plants secrete signaling molecules called flavonoids into the rhizosphere. These molecules activate the transcription of rhizobial nod genes, which encode proteins involved in the synthesis of signaling compounds named Nod factors (NFs). NFs, in turn, trigger changes in plant gene expression, cortical cell dedifferentiation and mitosis, depolarization of the root hair cell membrane potential and rearrangement of the actin cytoskeleton. Actin polymerization plays an important role in apical growth in hyphae and pollen tubes. Using sublethal concentrations of fluorescently labeled cytochalasin D (Cyt-Fl), we visualized the distribution of filamentous actin (F-actin) plus ends in living Phaseolus vulgaris and Arabidopsis root hairs during apical growth. We demonstrated that Cyt-Fl specifically labeled the newly available plus ends of actin microfilaments, which probably represent sites of polymerization. The addition of unlabeled competing cytochalasin reduced the signal, suggesting that the labeled and unlabeled forms of the drug bind to the same site on F-actin. Exposure to Rhizobium etli NFs resulted in a rapid increase in the number of F-actin plus ends in P. vulgaris root hairs and in the re-localization of F-actin plus ends to infection thread initiation sites. These data suggest that NFs promote the formation of F-actin plus ends, which results in actin cytoskeleton rearrangements that facilitate infection thread formation.
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Affiliation(s)
- Isaac Zepeda
- Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, UNAM, Apdo. Postal 510-3, Cuernavaca, Morelos 62250, Mexico
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42
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Bibeau JP, Vidali L. Morphological analysis of cell growth mutants in Physcomitrella. Methods Mol Biol 2014; 1080:201-13. [PMID: 24132431 DOI: 10.1007/978-1-62703-643-6_17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
This protocol describes a quantitative analysis of the morphology of small plants from the moss Physcomitrella patens. The protocol can be used for the analysis of growth phenotypes produced by transient RNA interference or for the analysis of stable mutant plants. Information is presented to guide the investigator in the choice of vectors and basic conditions to perform transient RNA interference in moss. Detailed directions and examples for fluorescence image acquisition of small regenerating moss plants are provided. Instructions for the use of an ImageJ-based macro for quantitative morphological analysis of these plants are also provided.
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Affiliation(s)
- Jeffrey P Bibeau
- Department of Biology and Biotechnology, Worcester Polytechnic institute, Worcester, MA, USA
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43
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Henty-Ridilla JL, Li J, Blanchoin L, Staiger CJ. Actin dynamics in the cortical array of plant cells. CURRENT OPINION IN PLANT BIOLOGY 2013; 16:678-87. [PMID: 24246228 DOI: 10.1016/j.pbi.2013.10.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/07/2013] [Accepted: 10/08/2013] [Indexed: 05/03/2023]
Abstract
The actin cytoskeleton changes in organization and dynamics as cellular functions are reprogrammed following responses to diverse stimuli, hormones, and developmental cues. How this is choreographed and what molecular players are involved in actin remodeling continues to be an area of intense scrutiny. Advances in imaging modalities and fluorescent fusion protein reporters have illuminated the strikingly dynamic behavior of single actin filaments at high spatial and temporal resolutions. This led to a model for the stochastic dynamic turnover of actin filaments and predicted the actions and responsibilities of several key actin-binding proteins. Recently, aspects of this model have been tested using powerful genetic strategies in both Arabidopsis and Physcomitrella. Collectively, the latest data emphasize the importance of filament severing activities and regulation of barbed-end availability as key facets of plant actin filament turnover.
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Cheng X, Wu Y, Guo J, Du B, Chen R, Zhu L, He G. A rice lectin receptor-like kinase that is involved in innate immune responses also contributes to seed germination. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 76:687-98. [PMID: 24033867 PMCID: PMC4285754 DOI: 10.1111/tpj.12328] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 08/14/2013] [Accepted: 09/05/2013] [Indexed: 05/20/2023]
Abstract
Seed germination and innate immunity both have significant effects on plant life spans because they control the plant's entry into the ecosystem and provide defenses against various external stresses, respectively. Much ecological evidence has shown that seeds with high vigor are generally more tolerant of various environmental stimuli in the field than those with low vigor. However, there is little genetic evidence linking germination and immunity in plants. Here, we show that the rice lectin receptor-like kinase OslecRK contributes to both seed germination and plant innate immunity. We demonstrate that knocking down the OslecRK gene depresses the expression of α-amylase genes, reducing seed viability and thereby decreasing the rate of seed germination. Moreover, it also inhibits the expression of defense genes, and so reduces the resistance of rice plants to fungal and bacterial pathogens as well as herbivorous insects. Yeast two-hybrid and co-immunoprecipitation experiments revealed that OslecRK interacts with an actin-depolymerizing factor (ADF) in vivo via its kinase domain. Moreover, the rice adf mutant exhibited a reduced seed germination rate due to the suppression of α-amylase gene expression. This mutant also exhibited depressed immune responses and reduced resistance to biotic stresses. Our results thus provide direct genetic evidence for a common physiological pathway connecting germination and immunity in plants. They also partially explain the common observation that high-vigor seeds often perform well in the field. The dual effects of OslecRK may be indicative of progressive adaptive evolution in rice.
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Affiliation(s)
- Xiaoyan Cheng
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan UniversityWuhan, 430072, China
| | - Yan Wu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan UniversityWuhan, 430072, China
| | - Jianping Guo
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan UniversityWuhan, 430072, China
| | - Bo Du
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan UniversityWuhan, 430072, China
| | - Rongzhi Chen
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan UniversityWuhan, 430072, China
| | - Lili Zhu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan UniversityWuhan, 430072, China
| | - Guangcun He
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan UniversityWuhan, 430072, China
- For correspondence (e-mail )
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Dong CH, Hong Y. Arabidopsis CDPK6 phosphorylates ADF1 at N-terminal serine 6 predominantly. PLANT CELL REPORTS 2013; 32:1715-28. [PMID: 23903947 DOI: 10.1007/s00299-013-1482-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 06/26/2013] [Accepted: 07/15/2013] [Indexed: 05/20/2023]
Abstract
KEY MESSAGE We found that Arabidopsis AtADF1 was phosphorylated by AtCDPK6 at serine 6 predominantly and the phosphoregulation plays a key role in the regulation of ADF1-mediated depolymerization of actin filaments. ABSTRACT Since actin-depolymerizing factor (ADF) is highly conserved among eukaryotes, it is one of the key modulators for actin organization. In plants, ADF is directly involved in the depolymerization of actin filaments, and therefore important for F-actin-dependent cellular activities. The activity of ADF is tightly controlled through a number of molecular mechanisms, including phosphorylation-mediated inactivation of ADF. To investigate Arabidopsis ADF1 phosphoregulation, we generated AtADF1 phosphorylation site-specific mutants. Using transient expression and stable transgenic approaches, we analyzed the ADF1 phosphorylation mutants in the regulation of actin filament organizations in plant cells. By in vitro phosphorylation assay, we showed that AtADF1 is phosphorylated by AtCDPK6 at serine 6 predominantly. Chemically induced expression of AtCDPK6 can negatively regulate the wild-type AtADF1 in depolymerizing actin filaments, but not those of the mutants AtADF1(S6A) and AtADF1(S6D). These results demonstrate a regulatory function of Arabidopsis CDPK6 in the N-terminal phosphorylation of AtADF1.
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Affiliation(s)
- Chun-Hai Dong
- College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, People's Republic of China,
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46
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Huang Y, Deng T, Zuo K. Cotton annexin proteins participate in the establishment of fiber cell elongation scaffold. PLANT SIGNALING & BEHAVIOR 2013; 8:25601. [PMID: 23838954 PMCID: PMC4002604 DOI: 10.4161/psb.25601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 06/30/2013] [Indexed: 06/02/2023]
Abstract
Cotton plant is one of the most important economic crops in the world which supplies natural fiber for textile industry. The crucial traits of cotton fiber quality are fiber length and strength, which are mostly determined by the fiber elongation stage. Annexins are assumed to be involved in regulating fiber elongation, but direct evidences remain elusive. Recently, we have investigated the activities of fiber-specific expressed annexins AnGb5/6 and their interacted proteins in cotton. AnGb5 and 6 can interact reciprocally to generate a protein macro-raft in cell membrane. This macro-raft is probably a stabilized scaffold for Actin1 organization. The actin assembling direction and density are correlated with AnGb6 gene expression and fiber expanding rate among three fiber length genotypes. These results suggest that annexins may act as the adaptor that linked fiber cell membrane to actin assembling. Due to the strong Ca (2+) and lipid binding ability of annexins, these results also indicate that annexins complex may function as an intermediate to receive Ca (2+) or lipid signals during fiber elongation.
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Miro B, Ismail AM. Tolerance of anaerobic conditions caused by flooding during germination and early growth in rice (Oryza sativa L.). FRONTIERS IN PLANT SCIENCE 2013; 4:269. [PMID: 23888162 PMCID: PMC3719019 DOI: 10.3389/fpls.2013.00269] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 07/02/2013] [Indexed: 05/20/2023]
Abstract
Rice is semi-aquatic, adapted to a wide range of hydrologies, from aerobic soils in uplands to anaerobic and flooded fields in waterlogged lowlands, to even deeply submerged soils in flood-prone areas. Considerable diversity is present in native rice landraces selected by farmers over centuries. Our understanding of the adaptive features of these landraces to native ecosystems has improved considerably over the recent past. In some cases, major genes associated with tolerance have been cloned, such as SUB1A that confers tolerance of complete submergence and SNORKEL genes that control plant elongation to escape deepwater. Modern rice varieties are sensitive to flooding during germination and early growth, a problem commonly encountered in rainfed areas, but few landraces capable of germination under these conditions have recently been identified, enabling research into tolerance mechanisms. Major QTLs were also identified, and are being targeted for molecular breeding and for cloning. Nevertheless, limited progress has been made in identifying regulatory processes for traits that are unique to tolerant genotypes, including faster germination and coleoptile elongation, formation of roots and leaves under hypoxia, ability to catabolize starch into simple sugars for subsequent use in glycolysis and fermentative pathways to generate energy. Here we discuss the state of knowledge on the role of the PDC-ALDH-ACS bypass and the ALDH enzyme as the likely candidates effective in tolerant rice genotypes. Potential involvement of factors such as cytoplasmic pH regulation, phytohormones, reactive oxygen species scavenging and other metabolites is also discussed. Further characterization of contrasting genotypes would help in elucidating the genetic and biochemical regulatory and signaling mechanisms associated with tolerance. This could facilitate breeding rice varieties suitable for direct seeding systems and guide efforts for improving waterlogging tolerance in other crops.
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Affiliation(s)
| | - Abdelbagi M. Ismail
- Crop and Environmental Sciences Division, International Rice Research InstituteManila, Philippines
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Furt F, Liu YC, Bibeau JP, Tüzel E, Vidali L. Apical myosin XI anticipates F-actin during polarized growth of Physcomitrella patens cells. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 73:417-428. [PMID: 23020796 DOI: 10.1111/tpj.12039] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 09/07/2012] [Accepted: 09/27/2012] [Indexed: 05/28/2023]
Abstract
Tip growth is essential for land colonization by bryophytes, plant sexual reproduction and water and nutrient uptake. Because this specialized form of polarized cell growth requires both a dynamic actin cytoskeleton and active secretion, it has been proposed that the F-actin-associated motor myosin XI is essential for this process. Nevertheless, a spatial and temporal relationship between myosin XI and F-actin during tip growth is not known in any plant cell. Here, we use the highly polarized cells of the moss Physcomitrella patens to show that myosin XI and F-actin localize, in vivo, at the same apical domain and that both signals fluctuate. Surprisingly, phase analysis shows that increase in myosin XI anticipates that of F-actin; in contrast, myosin XI levels at the tip fluctuate in identical phase with a vesicle marker. Pharmacological analysis using a low concentration of the actin polymerization inhibitor latrunculin B showed that the F-actin at the tip can be significantly diminished while myosin XI remains elevated in this region, suggesting that a mechanism exists to cluster myosin XI-associated structures at the cell's apex. In addition, this approach uncovered a mechanism for actin polymerization-dependent motility in the moss cytoplasm, where myosin XI-associated structures seem to anticipate and organize the actin polymerization machinery. From our results, we inferred a model where the interaction between myosin XI-associated vesicular structures and F-actin polymerization-driven motility function at the cell's apex to maintain polarized cell growth. We hypothesize this is a general mechanism for the participation of myosin XI and F-actin in tip growing cells.
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Affiliation(s)
- Fabienne Furt
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, MA 01609, USA
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Abstract
Tip growth is employed throughout the plant kingdom. Our understanding of tip growth has benefited from modern tools in molecular genetics, which have enabled the functional characterization of proteins mediating tip growth. Here we first discuss the evolutionary role of tip growth in land plants and then describe the prominent model tip-growth systems, elaborating on some advantages and disadvantages of each. Next we review the organization of tip-growing cells, the role of the cytoskeleton, and recent developments concerning the physiological basis of tip growth. Finally, we review advances in the understanding of the extracellular signals that are known to guide tip-growing cells.
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Affiliation(s)
- Caleb M Rounds
- Department of Biological Sciences, Mount Holyoke College, South Hadley, MA 01075, USA
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Wang WQ, Møller IM, Song SQ. Proteomic analysis of embryonic axis of Pisum sativum seeds during germination and identification of proteins associated with loss of desiccation tolerance. J Proteomics 2012; 77:68-86. [PMID: 22796356 DOI: 10.1016/j.jprot.2012.07.005] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Revised: 06/20/2012] [Accepted: 07/02/2012] [Indexed: 12/26/2022]
Abstract
Seed germination is an important stage in life cycle of higher plants. The germination processes and its associated loss of desiccation tolerance, however, are still poorly understood. In present study, pea seeds were used to study changes in embryonic axis proteome during germination by 2-DE and mass spectrometry. We identified a total of 139 protein spots showing a significant (>2-fold) change during germination. The results show that seed germination is not only the activation of a series of metabolic processes, but also involves reorganization of cellular structure and activation of protective systems. To uncouple the physiological processes of germination and its associated loss of desiccation tolerance, we used the fact that pea seeds have different desiccation tolerance when imbibed in water, CaCl(2) and methylviologen at the same germination stage. We compared the proteome amongst these seeds to identify the candidate proteins associated with the loss of desiccation tolerance and found a total of seven proteins - tubulin alpha-1 chain, seed biotin-containing protein SBP65, P54 protein, vicilin, vicilin-like antimicrobial peptides 2-3, convicilin and TCP-1/cpn60 chaperonin family protein. The metabolic function of these proteins indicates that seed desiccation tolerance is related to pathogen defense, protein conformation conservation and cell structure stabilization.
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Affiliation(s)
- Wei-Qing Wang
- Institute of Botany, Chinese Academy of Sciences, 20 Nanxincun, Xiangshan, Beijing 100093, China
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