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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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Pandey DK, Chaudhary B. Transcriptional loss of domestication-driven cytoskeletal GhPRF1 gene causes defective floral and fiber development in cotton (Gossypium). PLANT MOLECULAR BIOLOGY 2021; 107:519-532. [PMID: 34606035 DOI: 10.1007/s11103-021-01200-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
Constitutive- and fiber-specific RNAi of GhPRF1 gene illustrated strong correlation between domestication-driven profilin genes and floral/fiber architecture in cotton. During morpho-transformation of short-fuzz of wild cotton into the elongating spinnable fibers under the millennia of human selection, actin-polymerizing cytoskeletal profilin genes had undergone significant sequence alterations and spatiotemporal shift in their transcription levels. To comprehend the expression dynamics of profilin genes with their phenotypic implications, transgenic expression modulation of cotton profilin 1 (GhPRF1) gene was performed in the constitutive- and fiber-specific manner in Coker 310FR cotton cultivar. The constitutive GhPRF1-RNAi lines (35S:GhPRF1-RNAi) exhibited distorted 'monadelphous' staminal-tube, reduced pollen-viability and poorly developed fibers, whereas floral and fiber development of fiber-specific GhPRF1-RNAi lines showed no abnormalities. Moreover, the fiber-specific GhPRF1 overexpression lines (FBP7:GhPRF1-Ox) showed increased emergence of fiber-initials on the ovule surface, on the contrary to no fiber-initials in fiber-specific RNAi lines (FBP7:GhPRF1-RNAi). Interestingly, the average seed weight and fiber weight of FBP7:GhPRF1-Ox lines increased > 60% and > 38%, respectively, compared with FBP7:GhPRF1-RNAi lines and untransformed control seeds. On a molecular basis, the aberrant floral and fiber development of 35S:GhPRF1-RNAi lines was largely associated with sugar metabolism and hormone-signaling mechanisms. These observations illustrated the strong correlation between domestication-driven GhPRF genes, and floral/fiber development in cotton. Also, the enhanced agronomic traits in GhPRF1-Ox lines of cotton empowered us to recognize their imperative roles, and their future deployment for the sustainable cotton crop improvement.
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Affiliation(s)
- Dhananjay K Pandey
- School of Biotechnology, Gautam Buddha University, Greater Noida, UP, 201312, India
- Amity Institute of Biotechnology, Amity University, Ranchi, JH, 834001, India
| | - Bhupendra Chaudhary
- School of Biotechnology, Gautam Buddha University, Greater Noida, UP, 201312, India.
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3
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Identification and characterization of profilin gene family in rice. ELECTRON J BIOTECHN 2021. [DOI: 10.1016/j.ejbt.2021.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Sun Y, Liang W, Shen W, Feng H, Chen J, Si Z, Hu Y, Zhang T. G65V Substitution in Actin Disturbs Polymerization Leading to Inhibited Cell Elongation in Cotton. FRONTIERS IN PLANT SCIENCE 2019; 10:1486. [PMID: 31803216 PMCID: PMC6873290 DOI: 10.3389/fpls.2019.01486] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 10/25/2019] [Indexed: 06/10/2023]
Abstract
The importance of the actin cytoskeleton for proper cell development has been well established in a variety of organisms. Actin protein sequences are highly conserved, and each amino acid residue may be essential for its function. In this study, we report the isolation and characterization of GhLi 1 from an upland cotton mutant Ligon lintless-1 (Li1), which harbors the G65V substitution in its encoded actin protein. Li1 mutants exhibit pleiotropic malformed phenotypes, including dwarf plants, distorted organs, and extremely shortened fibers. Cytological analysis showed that the actin cytoskeleton was disorganized and the abundance of F-actin was decreased in the Li1 cells. Vesicles were aggregated into patches, and excessive cellulose synthase complexes were inserted into the plasma membrane during the secondary cell wall biosynthesis stage, which dramatically affected the morphology of the Li1 cells. Molecular model prediction suggested that the G65V substitution may affect the three-bodied G-actin interaction during F-actin assembly. Biochemical assays demonstrated that the recombinant GhLi1 protein disturbs actin dynamics by inhibiting the nucleation and elongation processes. Therefore, our findings demonstrate that the G65V substitution in actin had dominant-negative effects on cell elongation, by disturbing actin polymerization and actin cytoskeleton-based biological processes such as intracellular transportation.
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Affiliation(s)
- Yongwang Sun
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Wenhua Liang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Weijuan Shen
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Hao Feng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Jiedan Chen
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Zhanfeng Si
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Yan Hu
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
| | - Tianzhen Zhang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Hybrid R & D Engineering Center (the Ministry of Education), College of Agriculture, Nanjing Agricultural University, Nanjing, China
- Zhejiang Provincial Key Laboratory of Crop Genetic Resources, Institute of Crop Science, Plant Precision Breeding Academy, College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, China
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Sun T, Li S, Ren H. OsFH15, a class I formin, interacts with microfilaments and microtubules to regulate grain size via affecting cell expansion in rice. Sci Rep 2017; 7:6538. [PMID: 28747699 PMCID: PMC5529588 DOI: 10.1038/s41598-017-06431-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 06/13/2017] [Indexed: 11/23/2022] Open
Abstract
Grain size is an important agronomic trait determining rice yield and is mainly restricted by spikelet hull size. However, it remains largely unknown how the spikelet hull size is regulated. In this study, OsFH15, a class I formin protein in Oryza sativa, was found to be able to regulate the size of cells and spikelet hull. OsFH15-Cas9 and OsFH15-RNAi mutants had decreased grain size with reduced cell length, cell width and cell area of inner epidermal cells of the lemma compared with wild-type plants. By contrast, OsFH15-overexpressed plants had increased grain size with larger cells, as well as more abundant microtubules (MTs) and actin filaments (AFs) arrays. OsFH15 was mainly expressed in shoot apical meristem (SAM), spikelets, spikelet hulls and seeds in rice. In vitro biochemical experiments showed that OsFH15 can efficiently nucleate actin polymerization with or without profilin, can cap the barbed end of AFs, and can bind and bundle both AFs and MTs. OsFH15 can also crosslink AFs with MTs, and preferentially bind MTs to AFs. These results demonstrated that OsFH15 played an important role in grain-size control by affecting cell expansion through regulating AFs and MTs.
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Affiliation(s)
- Tiantian Sun
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Shanwei Li
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Haiyun Ren
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Science, Beijing Normal University, Beijing, 100875, China.
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Li S, Dong H, Pei W, Liu C, Zhang S, Sun T, Xue X, Ren H. LlFH1-mediated interaction between actin fringe and exocytic vesicles is involved in pollen tube tip growth. THE NEW PHYTOLOGIST 2017; 214:745-761. [PMID: 28092406 DOI: 10.1111/nph.14395] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/16/2016] [Indexed: 05/15/2023]
Abstract
Pollen tube tip growth is an extreme form of polarized cell growth, which requires polarized exocytosis based on a dynamic actin cytoskeleton. However, the molecular basis for the connection between actin filaments and exocytic vesicles is unclear. Here, we identified a Lilium longiflorum pollen-specific formin (LlFH1) and found that it localized at the apical vesicles and plasma membrane (PM). Overexpression of LlFH1 induced excessive actin cables in the tube tip region, and downregulation of LlFH1 eliminated the actin fringe. Fluorescence recovery after photobleaching (FRAP) analysis revealed that LlFH1-labeled exocytic vesicles exhibited an initial accumulation at the shoulder of the apex and coincided with the leading edge of the actin fringe. Time-lapse analysis suggested that nascent actin filaments followed the emergence of the apical vesicles, implying that LlFH1 at apical vesicles could initiate actin polymerization. Biochemical assays showed that LlFH1 FH1FH2 could nucleate actin polymerization, but then capped the actin filament at the barbed end and inhibited its elongation. However, in the presence of lily profilins, LlFH1 FH1FH2 could accelerate barbed-end actin elongation. In addition, LlFH1 FH1FH2 was able to bundle actin filaments. Thus, we propose that LlFH1 and profilin coordinate the interaction between the actin fringe and exocytic vesicle trafficking during pollen tube growth of lily.
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Affiliation(s)
- Shanwei Li
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Huaijian Dong
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Weike Pei
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Chaonan Liu
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Sha Zhang
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Tiantian Sun
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Xiuhua Xue
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
| | - Haiyun Ren
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing, 100875, China
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Salih H, Leng X, He SP, Jia YH, Gong WF, Du XM. Characterization of the early fiber development gene, Ligon-lintless 1 (Li1), using microarray. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.plgene.2016.03.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Pandey DK, Chaudhary B. Domestication-driven Gossypium profilin 1 (GhPRF1) gene transduces early flowering phenotype in tobacco by spatial alteration of apical/floral-meristem related gene expression. BMC PLANT BIOLOGY 2016; 16:112. [PMID: 27177585 PMCID: PMC4866011 DOI: 10.1186/s12870-016-0798-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 05/02/2016] [Indexed: 05/26/2023]
Abstract
BACKGROUND Plant profilin genes encode core cell-wall structural proteins and are evidenced for their up-regulation under cotton domestication. Notwithstanding striking discoveries in the genetics of cell-wall organization in plants, little is explicit about the manner in which profilin-mediated molecular interplay and corresponding networks are altered, especially during cellular signalling of apical meristem determinacy and flower development. RESULTS Here we show that the ectopic expression of GhPRF1 gene in tobacco resulted in the hyperactivation of apical meristem and early flowering phenotype with increased flower number in comparison to the control plants. Spatial expression alteration in CLV1, a key meristem-determinacy gene, is induced by the GhPRF1 overexpression in a WUS-dependent manner and mediates cell signalling to promote flowering. But no such expression alterations are recorded in the GhPRF1-RNAi lines. The GhPRF1 transduces key positive flowering regulator AP1 gene via coordinated expression of FT4, SOC1, FLC1 and FT1 genes involved in the apical-to-floral meristem signalling cascade which is consistent with our in silico profilin interaction data. Remarkably, these positive and negative flowering regulators are spatially controlled by the Actin-Related Protein (ARP) genes, specifically ARP4 and ARP6 in proximate association with profilins. This study provides a novel and systematic link between GhPRF1 gene expression and the flower primordium initiation via up-regulation of the ARP genes, and an insight into the functional characterization of GhPRF1 gene acting upstream to the flowering mechanism. Also, the transgenic plants expressing GhPRF1 gene show an increase in the plant height, internode length, leaf size and plant vigor. CONCLUSIONS Overexpression of GhPRF1 gene induced early and increased flowering in tobacco with enhanced plant vigor. During apical meristem determinacy and flower development, the GhPRF1 gene directly influences key flowering regulators through ARP-genes, indicating for its role upstream in the apical-to-floral meristem signalling cascade.
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Affiliation(s)
- Dhananjay K Pandey
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201310, UP, India
| | - Bhupendra Chaudhary
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201310, UP, India.
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Mujahid H, Pendarvis K, Reddy JS, Nallamilli BRR, Reddy KR, Nanduri B, Peng Z. Comparative Proteomic Analysis of Cotton Fiber Development and Protein Extraction Method Comparison in Late Stage Fibers. Proteomes 2016; 4:proteomes4010007. [PMID: 28248216 PMCID: PMC5217364 DOI: 10.3390/proteomes4010007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/19/2016] [Accepted: 01/28/2016] [Indexed: 12/21/2022] Open
Abstract
The distinct stages of cotton fiber development and maturation serve as a single-celled model for studying the molecular mechanisms of plant cell elongation, cell wall development and cellulose biosynthesis. However, this model system of plant cell development is compromised for proteomic studies due to a lack of an efficient protein extraction method during the later stages of fiber development, because of a recalcitrant cell wall and the presence of abundant phenolic compounds. Here, we compared the quality and quantities of proteins extracted from 25 dpa (days post anthesis) fiber with multiple protein extraction methods and present a comprehensive quantitative proteomic study of fiber development from 10 dpa to 25 dpa. Comparative analysis using a label-free quantification method revealed 287 differentially-expressed proteins in the 10 dpa to 25 dpa fiber developmental period. Proteins involved in cell wall metabolism and regulation, cytoskeleton development and carbohydrate metabolism among other functional categories in four fiber developmental stages were identified. Our studies provide protocols for protein extraction from maturing fiber tissues for mass spectrometry analysis and expand knowledge of the proteomic profile of cotton fiber development.
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Affiliation(s)
- Hana Mujahid
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Ken Pendarvis
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi Agricultural and Forestry Experiment Station, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Joseph S Reddy
- College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Babi Ramesh Reddy Nallamilli
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA.
| | - K R Reddy
- Department of Plant and Soil Sciences, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Bindu Nanduri
- College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Zhaohua Peng
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS 39762, USA.
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Wang X, Xu R, Wang R, Liu A. Transcriptome analysis of Sacha Inchi (Plukenetia volubilis L.) seeds at two developmental stages. BMC Genomics 2012; 13:716. [PMID: 23256450 PMCID: PMC3574040 DOI: 10.1186/1471-2164-13-716] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 12/16/2012] [Indexed: 11/22/2022] Open
Abstract
Background Sacha Inchi (Plukenetia volubilis L., Euphorbiaceae) is a potential oilseed crop because the seeds of this plant are rich in unsaturated fatty acids (FAs). In particular, the fatty acid composition of its seed oil differs markedly in containing large quantities of α-linolenic acid (18C:3, a kind of ω-3 FAs). However, little is known about the molecular mechanisms responsible for biosynthesis of unsaturated fatty acids in the developing seeds of this species. Transcriptome data are needed to better understand these mechanisms. Results In this study, de novo transcriptome assembly and gene expression analysis were performed using Illumina sequencing technology. A total of 52.6 million 90-bp paired-end reads were generated from two libraries constructed at the initial stage and fast oil accumulation stage of seed development. These reads were assembled into 70,392 unigenes; 22,179 unigenes showed a 2-fold or greater expression difference between the two libraries. Using this data we identified unigenes that may be involved in de novo FA and triacylglycerol biosynthesis. In particular, a number of unigenes encoding desaturase for formation of unsaturated fatty acids with high expression levels in the fast oil accumulation stage compared with the initial stage of seed development were identified. Conclusions This study provides the first comprehensive dataset characterizing Sacha Inchi gene expression at the transcriptional level. These data provide the foundation for further studies on molecular mechanisms underlying oil accumulation and PUFA biosynthesis in Sacha Inchi seeds. Our analyses facilitate understanding of the molecular mechanisms responsible for the high unsaturated fatty acids (especially α-linolenic acid) accumulation in Sacha Inchi seeds.
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Affiliation(s)
- Xiaojuan Wang
- Key Laboratory of Tropical Plant Resource Science, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, 88 Xuefu Road, Kunming 650223, China
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Liu K, Sun J, Yao L, Yuan Y. Transcriptome analysis reveals critical genes and key pathways for early cotton fiber elongation in Ligon lintless-1 mutant. Genomics 2012; 100:42-50. [PMID: 22576057 DOI: 10.1016/j.ygeno.2012.04.007] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 04/24/2012] [Accepted: 04/26/2012] [Indexed: 12/13/2022]
Abstract
Fiber length is a key determinant of cotton yield and quality. Using a monogenic dominant cotton mutant Ligon lintless-1 with extremely short fibers, we employed microarray technology and quantitative real time PCR to compare transcriptomes of Li(1) and the normal wild-type TM-1, the results showed that only a few genes differentially expressed in 0 days postanthesis (DPA) ovules and 3 DPA fibers, whereas 577 transcripts differentially expressed in 6 DPA fibers. 6 DPA is probably a key phase determining fiber elongation. Gene ontology analyses showed such processes as response to stimulus, signal transduction, and lipid metabolism were readjusted by the mutant gene. Pathway studio analysis indicated that auxin signaling and sugar signaling pathways play major roles in modulation of early fiber elongation. This work provides new insight into the mechanisms of fiber development, and offers novel genes as potential objects for genetic manipulation to achieve improvement of fiber properties.
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Affiliation(s)
- Kang Liu
- The State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
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Jimenez-Lopez JC, Morales S, Castro AJ, Volkmann D, Rodríguez-García MI, Alché JDD. Characterization of profilin polymorphism in pollen with a focus on multifunctionality. PLoS One 2012; 7:e30878. [PMID: 22348028 PMCID: PMC3279341 DOI: 10.1371/journal.pone.0030878] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 12/28/2011] [Indexed: 12/20/2022] Open
Abstract
Profilin, a multigene family involved in actin dynamics, is a multiple partners-interacting protein, as regard of the presence of at least of three binding domains encompassing actin, phosphoinositide lipids, and poly-L-proline interacting patches. In addition, pollen profilins are important allergens in several species like Olea europaea L. (Ole e 2), Betula pendula (Bet v 2), Phleum pratense (Phl p 12), Zea mays (Zea m 12) and Corylus avellana (Cor a 2). In spite of the biological and clinical importance of these molecules, variability in pollen profilin sequences has been poorly pointed out up until now. In this work, a relatively high number of pollen profilin sequences have been cloned, with the aim of carrying out an extensive characterization of their polymorphism among 24 olive cultivars and the above mentioned plant species. Our results indicate a high level of variability in the sequences analyzed. Quantitative intra-specific/varietal polymorphism was higher in comparison to inter-specific/cultivars comparisons. Multi-optional posttranslational modifications, e.g. phosphorylation sites, physicochemical properties, and partners-interacting functional residues have been shown to be affected by profilin polymorphism. As a result of this variability, profilins yielded a clear taxonomic separation between the five plant species. Profilin family multifunctionality might be inferred by natural variation through profilin isovariants generated among olive germplasm, as a result of polymorphism. The high variability might result in both differential profilin properties and differences in the regulation of the interaction with natural partners, affecting the mechanisms underlying the transmission of signals throughout signaling pathways in response to different stress environments. Moreover, elucidating the effect of profilin polymorphism in adaptive responses like actin dynamics, and cellular behavior, represents an exciting research goal for the future.
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Affiliation(s)
- Jose C. Jimenez-Lopez
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, High Council for Scientific Research, Granada, Spain
| | - Sonia Morales
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, High Council for Scientific Research, Granada, Spain
| | - Antonio J. Castro
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, High Council for Scientific Research, Granada, Spain
| | - Dieter Volkmann
- Institute of Cellular and Molecular Botany, Department of Plant Cell Biology, University of Bonn, Bonn, Germany
| | - María I. Rodríguez-García
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, High Council for Scientific Research, Granada, Spain
| | - Juan de D. Alché
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, High Council for Scientific Research, Granada, Spain
- * E-mail:
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Parallel up-regulation of the profilin gene family following independent domestication of diploid and allopolyploid cotton (Gossypium). Proc Natl Acad Sci U S A 2011; 108:21152-7. [PMID: 22160709 DOI: 10.1073/pnas.1115926109] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Cotton is remarkable among our major crops in that four species were independently domesticated, two allopolyploids and two diploids. In each case thousands of years of human selection transformed sparsely flowering, perennial shrubs into highly productive crops with seeds bearing the vastly elongated and abundant single-celled hairs that comprise modern cotton fiber. The genetic underpinnings of these transformations are largely unknown, but comparative gene expression profiling experiments have demonstrated up-regulation of profilin accompanying domestication in all three species for which wild forms are known. Profilins are actin monomer binding proteins that are important in cytoskeletal dynamics and in cotton fiber elongation. We show that Gossypium diploids contain six profilin genes (GPRF1-GPRF6), located on four different chromosomes (eight chromosomes in the allopolyploid). All but one profilin (GPRF6) are expressed during cotton fiber development, and both homeologs of GPRF1-GPRF5 are expressed in fibers of the allopolyploids. Remarkably, quantitative RT-PCR and RNAseq data demonstrate that GPRF1-GPRF5 are all up-regulated, in parallel, in the three independently domesticated cottons in comparison with their wild counterparts. This result was additionally supported by iTRAQ proteomic data. In the allopolyploids, there This usage of novel should be fine, since it refers to a novel evolutionary process, not a novel discovery has been novel recruitment of the sixth profilin gene (GPRF6) as a result of domestication. This parallel up-regulation of an entire gene family in multiple species in response to strong directional selection is without precedent and suggests unwitting selection on one or more upstream transcription factors or other proteins that coordinately exercise control over profilin expression.
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Generation, annotation and analysis of first large-scale expressed sequence tags from developing fiber of Gossypium barbadense L. PLoS One 2011; 6:e22758. [PMID: 21829504 PMCID: PMC3145671 DOI: 10.1371/journal.pone.0022758] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Accepted: 06/29/2011] [Indexed: 11/22/2022] Open
Abstract
Background Cotton fiber is the world's leading natural fiber used in the manufacture of textiles. Gossypium is also the model plant in the study of polyploidization, evolution, cell elongation, cell wall development, and cellulose biosynthesis. G. barbadense L. is an ideal candidate for providing new genetic variations useful to improve fiber quality for its superior properties. However, little is known about fiber development mechanisms of G. barbadense and only a few molecular resources are available in GenBank. Methodology and Principal Findings In total, 10,979 high-quality expressed sequence tags (ESTs) were generated from a normalized fiber cDNA library of G. barbadense. The ESTs were clustered and assembled into 5852 unigenes, consisting of 1492 contigs and 4360 singletons. The blastx result showed 2165 unigenes with significant similarity to known genes and 2687 unigenes with significant similarity to genes of predicted proteins. Functional classification revealed that unigenes were abundant in the functions of binding, catalytic activity, and metabolic pathways of carbohydrate, amino acid, energy, and lipids. The function motif/domain-related cytoskeleton and redox homeostasis were enriched. Among the 5852 unigenes, 282 and 736 unigenes were identified as potential cell wall biosynthesis and transcription factors, respectively. Furthermore, the relationships among cotton species or between cotton and other model plant systems were analyzed. Some putative species-specific unigenes of G. barbadense were highlighted. Conclusions/Significance The ESTs generated in this study are from the first large-scale EST project for G. barbadense and significantly enhance the number of G. barbadense ESTs in public databases. This knowledge will contribute to cotton improvements by studying fiber development mechanisms of G. barbadense, establishing a breeding program using marker-assisted selection, and discovering candidate genes related to important agronomic traits of cotton through oligonucleotide array. Our work will also provide important resources for comparative genomics, polyploidization, and genome evolution among Gossypium species.
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Argiriou A, Kalivas A, Michailidis G, Tsaftaris A. Characterization of PROFILIN genes from allotetraploid (Gossypium hirsutum) cotton and its diploid progenitors and expression analysis in cotton genotypes differing in fiber characteristics. Mol Biol Rep 2011; 39:3523-32. [PMID: 21725637 DOI: 10.1007/s11033-011-1125-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 06/20/2011] [Indexed: 11/26/2022]
Abstract
The actin-binding protein profilin (PRF) plays an important role in cell growth and expansion by regulating the organization of the actin filaments. Recent studies have reported association between fiber elongation in cultivated cotton (Gossypium hirsutum) and PRF expression. In the present study, we cloned four genomic clones from allotetraploid cotton (G. hirsutum) and its putative diploid progenitors (G. arboreum and G. raimondii) designated GhPRF1_A, GhPRF1_D, GaPRF1, and GrPRF1 encoding cotton PRF and characterized their genomic structure, phylogenetic relationships and promoter structure. Sequence analysis of the coding regions of all clones resulted in a single protein product which revealed more than 80% similarity to most plant PRFs and a typical organization with an actin-binding and a polybasic phospholipid binding motif at the carboxy terminus. DNA blot hybridization suggested that PRF gene is present with more than one copy in the allotetraploid species G. hirsutum. Expression analysis performed in various organs of cultivated cotton revealed that the PRF gene was preferentially expressed in cotton fibers. Very low levels of expression were observed in whole flowers, while PRF transcripts were not detected in other organs examined. Furthermore, higher levels of expression were observed at the early stages of cotton fiber development (at 10 days post anthesis), indicative that this gene may play a major role in the early stages of cotton fiber development. Quantitation of the expression by real-time PCR revealed higher expression levels in a G. hirsutum variety with higher fiber percentage compared to a variety with lower percentage. In addition, higher levels of expression were found in cultivated allotetraploid G. barbadense cotton species with higher fiber length in comparison to cultivated allotetraploid G. hirsutum.
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Yang W, Ren S, Zhang X, Gao M, Ye S, Qi Y, Zheng Y, Wang J, Zeng L, Li Q, Huang S, He Z. BENT UPPERMOST INTERNODE1 encodes the class II formin FH5 crucial for actin organization and rice development. THE PLANT CELL 2011; 23:661-80. [PMID: 21307285 PMCID: PMC3077787 DOI: 10.1105/tpc.110.081802] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 01/08/2011] [Accepted: 01/18/2011] [Indexed: 05/18/2023]
Abstract
The actin cytoskeleton is an important regulator of cell expansion and morphogenesis in plants. However, the molecular mechanisms linking the actin cytoskeleton to these processes remain largely unknown. Here, we report the functional analysis of rice (Oryza sativa) FH5/BENT UPPERMOST INTERNODE1 (BUI1), which encodes a formin-type actin nucleation factor and affects cell expansion and plant morphogenesis in rice. The bui1 mutant displayed pleiotropic phenotypes, including bent uppermost internode, dwarfism, wavy panicle rachis, and enhanced gravitropic response. Cytological observation indicated that the growth defects of bui1 were caused mainly by inhibition of cell expansion. Map-based cloning revealed that BUI1 encodes the class II formin FH5. FH5 contains a phosphatase tensin-like domain at its amino terminus and two highly conserved formin-homology domains, FH1 and FH2. In vitro biochemical analyses indicated that FH5 is capable of nucleating actin assembly from free or profilin-bound monomeric actin. FH5 also interacts with the barbed end of actin filaments and prevents the addition and loss of actin subunits from the same end. Interestingly, the FH2 domain of FH5 could bundle actin filaments directly and stabilize actin filaments in vitro. Consistent with these in vitro biochemical activities of FH5/BUI1, the amount of filamentous actin decreased, and the longitudinal actin cables almost disappeared in bui1 cells. The FH2 or FH1FH2 domains of FH5 could also bind to and bundle microtubules in vitro. Thus, our study identified a rice formin protein that regulates de novo actin nucleation and spatial organization of the actin filaments, which are important for proper cell expansion and rice morphogenesis.
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Affiliation(s)
- Weibing Yang
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Sulin Ren
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiaoming Zhang
- State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Mingjun Gao
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Shenghai Ye
- State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Yongbin Qi
- State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China
| | - Yiyan Zheng
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Juan Wang
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Longjun Zeng
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Qun Li
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Shanjin Huang
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Zuhua He
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
- Address correspondence to
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Zhang Z, Zhang Y, Tan H, Wang Y, Li G, Liang W, Yuan Z, Hu J, Ren H, Zhang D. RICE MORPHOLOGY DETERMINANT encodes the type II formin FH5 and regulates rice morphogenesis. THE PLANT CELL 2011; 23:681-700. [PMID: 21307283 PMCID: PMC3077795 DOI: 10.1105/tpc.110.081349] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 01/01/2011] [Accepted: 01/18/2011] [Indexed: 05/19/2023]
Abstract
Multicellular organisms contain a large number of formins; however, their physiological roles in plants remain poorly understood. Here, we reveal that formin homology 5 (FH5), a type II formin mutated in rice morphology determinant (rmd), plays a crucial role in determining rice (Oryza sativa) morphology. FH5/RMD encodes a formin-like protein consisting of an N-terminal phosphatase tensin (PTEN)-like domain, an FH1 domain, and an FH2 domain. The rmd mutants display a bending growth pattern in seedlings, are stunted as adult plants, and have aberrant inflorescence (panicle) and seed shape. Cytological analysis showed that rmd mutants have severe cell elongation defects and abnormal microtubule and microfilament arrays. FH5/RMD is ubiquitously expressed in rice tissues, and its protein localization to the chloroplast surface is mediated by the PTEN domain. Biochemical assays demonstrated that recombinant FH5 protein can nucleate actin polymerization from monomeric G-actin or actin/profilin complexes, cap the barbed end of actin filaments, and bundle actin filaments in vitro. Moreover, FH5 can directly bind to and bundle microtubules through its FH2 domain in vitro. Our findings suggest that the rice formin protein FH5 plays a critical role in determining plant morphology by regulating actin dynamics and proper spatial organization of microtubules and microfilaments.
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Affiliation(s)
- Zheng Zhang
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yi Zhang
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Science, Beijing Normal University, Beijing 100875, China
| | - Hexin Tan
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ying Wang
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Gang Li
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Wanqi Liang
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zheng Yuan
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jianping Hu
- Michigan State University–Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824
| | - Haiyun Ren
- Key Laboratory of Cell Proliferation and Regulation Biology of the Ministry of Education, College of Life Science, Beijing Normal University, Beijing 100875, China
| | - Dabing Zhang
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Bio-X Center, Key Laboratory of Genetics and Development and Neuropsychiatric Diseases, Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, China
- Address correspondence to
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Intracellular Movements: Integration at the Cellular Level as Reflected in the Organization of Organelle Movements. MECHANICAL INTEGRATION OF PLANT CELLS AND PLANTS 2011. [DOI: 10.1007/978-3-642-19091-9_4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Rapp RA, Haigler CH, Flagel L, Hovav RH, Udall JA, Wendel JF. Gene expression in developing fibres of Upland cotton (Gossypium hirsutum L.) was massively altered by domestication. BMC Biol 2010; 8:139. [PMID: 21078138 PMCID: PMC2992495 DOI: 10.1186/1741-7007-8-139] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2010] [Accepted: 11/15/2010] [Indexed: 12/16/2022] Open
Abstract
Background Understanding the evolutionary genetics of modern crop phenotypes has a dual relevance to evolutionary biology and crop improvement. Modern upland cotton (Gossypium hirsutum L.) was developed following thousands of years of artificial selection from a wild form, G. hirsutum var. yucatanense, which bears a shorter, sparser, layer of single-celled, ovular trichomes ('fibre'). In order to gain an insight into the nature of the developmental genetic transformations that accompanied domestication and crop improvement, we studied the transcriptomes of cotton fibres from wild and domesticated accessions over a developmental time course. Results Fibre cells were harvested between 2 and 25 days post-anthesis and encompassed the primary and secondary wall synthesis stages. Using amplified messenger RNA and a custom microarray platform designed to interrogate expression for 40,430 genes, we determined global patterns of expression during fibre development. The fibre transcriptome of domesticated cotton is far more dynamic than that of wild cotton, with over twice as many genes being differentially expressed during development (12,626 versus 5273). Remarkably, a total of 9465 genes were diagnosed as differentially expressed between wild and domesticated fibres when summed across five key developmental time points. Human selection during the initial domestication and subsequent crop improvement has resulted in a biased upregulation of components of the transcriptional network that are important for agronomically advanced fibre, especially in the early stages of development. About 15% of the differentially expressed genes in wild versus domesticated cotton fibre have no homology to the genes in databases. Conclusions We show that artificial selection during crop domestication can radically alter the transcriptional developmental network of even a single-celled structure, affecting nearly a quarter of the genes in the genome. Gene expression during fibre development within accessions and expression alteration arising from evolutionary change appears to be 'modular' - complex genic networks have been simultaneously and similarly transformed, in a coordinated fashion, as a consequence of human-mediated selection. These results highlight the complex alteration of the global gene expression machinery that resulted from human selection for a longer, stronger and finer fibre, as well as other aspects of fibre physiology that were not consciously selected. We illustrate how the data can be mined for genes that were unwittingly targeted by aboriginal and/or modern domesticators during crop improvement and/or which potentially control the improved qualities of domesticated cotton fibre. See Commentary: http://www.biomedcentral.com/1741-7007/8/137
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Affiliation(s)
- Ryan A Rapp
- Department of Ecology, 251 Bessey Hall, Iowa State University, Ames, IA 50011, USA
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Wang J, Wang HY, Zhao PM, Han LB, Jiao GL, Zheng YY, Huang SJ, Xia GX. Overexpression of a profilin (GhPFN2) promotes the progression of developmental phases in cotton fibers. PLANT & CELL PHYSIOLOGY 2010; 51:1276-90. [PMID: 20558432 DOI: 10.1093/pcp/pcq086] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Cotton fiber development at the stages of elongation and secondary wall synthesis determines the traits of fiber length and strength. To date, the mechanisms controlling the progression of these two phases remain elusive. In this work, the function of a fiber-preferential actin-binding protein (GhPFN2) was characterized by cytological and molecular studies on the fibers of transgenic green-colored cotton (Gossypium hirsutum) through three successive generations. Overexpression of GhPFN2 caused pre-terminated cell elongation, resulting in a marked decrease in the length of mature fibers. Cytoskeleton staining and quantitative assay revealed that thicker and more abundant F-actin bundles formed during the elongation stage in GhPFN2-overexpressing fibers. Accompanying this alteration, the developmental reorientation of transverse microtubules to the oblique direction was advanced by 2 d at the period of transition from elongation to secondary wall deposition. Birefringence and reverse transcription-PCR analyses showed that earlier onset of secondary wall synthesis occurred in parallel. These data demonstrate that formation of the higher actin structure plays a determinant role in the progression of developmental phases in cotton fibers, and that GhPFN2 acts as a critical modulator in this process. Such a function of the actin cytoskeleton in cell phase conversion may be common to other secondary wall-containing plant cells.
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Affiliation(s)
- Juan Wang
- Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
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Wang H, Guo Y, Lv F, Zhu H, Wu S, Jiang Y, Li F, Zhou B, Guo W, Zhang T. The essential role of GhPEL gene, encoding a pectate lyase, in cell wall loosening by depolymerization of the de-esterified pectin during fiber elongation in cotton. PLANT MOLECULAR BIOLOGY 2010; 72:397-406. [PMID: 20131110 DOI: 10.1007/s11103-009-9578-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Accepted: 11/09/2009] [Indexed: 05/08/2023]
Abstract
Cotton fiber elongation, largely achieved by cell wall loosening, is an important stage during cotton fiber development. In this present research, a fiber preferential cDNA encoding a pectate lyase (PEL) which could exclusively degrade the de-esterified pectin was isolated from a cotton (Gossypium hirsutum) fiber cDNA library. Subsequently, the corresponding PEL genes were isolated from four different cotton species and characterized. In vitro enzyme assays indicated that GhPEL really exhibited cleavage-activity against de-esterified pectin. The temporal-spatial expression analyses revealed that the GhPEL gene was preferentially expressed in fibers at 10 days-post anthesis (DPA). Antisense GhPEL transgenic cotton plants were generated by Agrobacterium-mediated transformation. Six homozygous lines, each with one or two copies of the transgene inserted as determined by southern blot analysis of the NPTII gene, were selected for further functional analysis. The GhPEL expression during fiber elongation in these transgenic lines was significantly suppressed in various degrees. Furthermore, the reduction of GhPEL enzymatic activity by decreasing GhPEL transcripts severely affected the degradation of de-esterified pectin in primary cell walls of transgenic cotton fibers, which consequently blocked cell wall loosening in early fiber development. Ultimately, the fiber elongation of all these transgenic lines was repressed. These results suggested that GhPEL may play an important role in the process of normal fiber elongation in cotton.
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Affiliation(s)
- Haihai Wang
- National Key Laboratory of Crop Genetics & Germplasm Enhancement, Cotton Research Institute, Nanjing Agricultural University, 210095 Nanjing, China
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Ye J, Zheng Y, Yan A, Chen N, Wang Z, Huang S, Yang Z. Arabidopsis formin3 directs the formation of actin cables and polarized growth in pollen tubes. THE PLANT CELL 2009; 21:3868-84. [PMID: 20023198 PMCID: PMC2814512 DOI: 10.1105/tpc.109.068700] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 11/07/2009] [Accepted: 11/18/2009] [Indexed: 05/18/2023]
Abstract
Cytoplasmic actin cables are the most prominent actin structures in plant cells, but the molecular mechanism underlying their formation is unknown. The function of these actin cables, which are proposed to modulate cytoplasmic streaming and intracellular movement of many organelles in plants, has not been studied by genetic means. Here, we show that Arabidopsis thaliana formin3 (AFH3) is an actin nucleation factor responsible for the formation of longitudinal actin cables in pollen tubes. The Arabidopsis AFH3 gene encodes a 785-amino acid polypeptide, which contains a formin homology 1 (FH1) and a FH2 domain. In vitro analysis revealed that the AFH3 FH1FH2 domains interact with the barbed end of actin filaments and have actin nucleation activity in the presence of G-actin or G actin-profilin. Overexpression of AFH3 in tobacco (Nicotiana tabacum) pollen tubes induced excessive actin cables, which extended into the tubes' apices. Specific downregulation of AFH3 eliminated actin cables in Arabidopsis pollen tubes and reduced the level of actin polymers in pollen grains. This led to the disruption of the reverse fountain streaming pattern in pollen tubes, confirming a role for actin cables in the regulation of cytoplasmic streaming. Furthermore, these tubes became wide and short and swelled at their tips, suggesting that actin cables may regulate growth polarity in pollen tubes. Thus, AFH3 regulates the formation of actin cables, which are important for cytoplasmic streaming and polarized growth in pollen tubes.
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Affiliation(s)
- Jianrong Ye
- College of Biological Science, China Agricultural University, Beijing 100193, China
- China Agricultural University-University of California-Riverside Joint Center for Biological Sciences and Biotechnology, China Agricultural University, Beijing 100193, China
| | - Yiyan Zheng
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - An Yan
- China Agricultural University-University of California-Riverside Joint Center for Biological Sciences and Biotechnology, China Agricultural University, Beijing 100193, China
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute of Integrative Genome Biology, University of California, Riverside, California 92521
| | - Naizhi Chen
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Zhangkui Wang
- College of Biological Science, China Agricultural University, Beijing 100193, China
- China Agricultural University-University of California-Riverside Joint Center for Biological Sciences and Biotechnology, China Agricultural University, Beijing 100193, China
| | - Shanjin Huang
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
- Address correspondence to or
| | - Zhenbiao Yang
- China Agricultural University-University of California-Riverside Joint Center for Biological Sciences and Biotechnology, China Agricultural University, Beijing 100193, China
- Department of Botany and Plant Sciences, Center for Plant Cell Biology, Institute of Integrative Genome Biology, University of California, Riverside, California 92521
- Address correspondence to or
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Chen N, Qu X, Wu Y, Huang S. Regulation of actin dynamics in pollen tubes: control of actin polymer level. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2009; 51:740-750. [PMID: 19686371 DOI: 10.1111/j.1744-7909.2009.00850.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Actin cytoskeleton undergoes rapid reorganization in response to internal and external cues. How the dynamics of actin cytoskeleton are regulated, and how its dynamics relate to its function are fundamental questions in plant cell biology. The pollen tube is a well characterized actin-based cell morphogenesis in plants. One of the striking features of actin cytoskeleton characterized in the pollen tube is its surprisingly low level of actin polymer. This special phenomenon might relate to the function of actin cytoskeleton in pollen tubes. Understanding the molecular mechanism underlying this special phenomenon requires careful analysis of actin-binding proteins that modulate actin dynamics directly. Recent biochemical and biophysical analyses of several highly conserved plant actin-binding proteins reveal unusual and unexpected properties, which emphasizes the importance of carefully analyzing their action mechanism and cellular activity. In this review, we highlight an actin monomer sequestering protein, a barbed end capping protein and an F-actin severing and dynamizing protein in plant. We propose that these proteins function in harmony to regulate actin dynamics and maintain the low level of actin polymer in pollen tubes.
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Affiliation(s)
- Naizhi Chen
- Center for Signal Transduction and Metabolomics, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
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Abstract
Many biological processes require the co-operative involvement of both microtubules and microfilaments; however, only a few proteins mediating the interaction between microtubules and microfilaments have been identified from plants. In the present study, a cotton kinesin GhKCH2, which contains a CH (calponin homology) domain at the N-terminus, was analysed in vitro and in vivo in order to understand its interaction with the two cytoskeletal elements. A specific antibody against GhKCH2 was prepared and used for immunolabelling experiments. Some GhKCH2 spots appeared along a few microtubules and microfilaments in developing cotton fibres. The His-tagged N-terminus of GhKCH2 (termed GhKCH2-N) could co-precipitate with microfilaments and strongly bind to actin filaments at a ratio of monomeric actin/GhKCH2-N of 1:0.6. The full-length GhKCH2 recombinant protein was shown to bind to and cross-link microtubules and microfilaments in vitro. A GFP-fusion protein GFP–GhKCH2 transiently overexpressed in Arabidopsis protoplasts decorated both microtubules and microfilaments, confirming the binding ability and specificities of GhKCH2 on microtubules and microfilaments in living plant cells. The results of the present study demonstrate that GhKCH2, a plant-specific microtubule-dependent motor protein, not only interacts with microtubules, but also strongly binds to microfilaments. The cytoskeletal dual-binding and cross-linking ability of GhKCH2 may be involved in the interaction between microtubules and microfilaments and the biological processes they co-ordinate together in cotton cells.
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Wang HY, Wang J, Gao P, Jiao GL, Zhao PM, Li Y, Wang GL, Xia GX. Down-regulation of GhADF1 gene expression affects cotton fibre properties. PLANT BIOTECHNOLOGY JOURNAL 2009; 7:13-23. [PMID: 18761653 DOI: 10.1111/j.1467-7652.2008.00367.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Cotton fibre is the most important natural fibres for textile industry. To date, the mechanism that governs the development of fibre traits is largely unknown. In this study, we have characterized the function of a member of the actin depolymerizing factor (ADF) family in Gossypium hirsutum by down-regulation of the gene (designated as GhADF1) expression in the transgenic cotton plants. We observed that both the fibre length and strength of the GhADF1-underexpressing plants increased as compared to the wild-type fibre, and transgenic fibres contained more abundant F-actin filaments in the cortical region of the cells. Moreover, the secondary cell wall of the transgenic fibre appeared thicker and the cellulose content was higher than that of the control fibre. Our results suggest that organization of actin cytoskeleton regulated by actin-associated proteins such as GhADF1 plays a critical role in the processes of elongation and secondary cell wall formation during fibre development. Additionally, our study provided a candidate intrinsic gene for the improvement of fibre traits via genetic engineering.
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Affiliation(s)
- Hai-Yun Wang
- National Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
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Yajun H, Wangzhen G, Xinlian S, Tianzhen Z. Molecular cloning and characterization of a cytosolic glutamine synthetase gene, a fiber strength-associated gene in cotton. PLANTA 2008; 228:473-83. [PMID: 18560885 DOI: 10.1007/s00425-008-0751-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Accepted: 05/08/2008] [Indexed: 05/12/2023]
Abstract
An expressed sequence tag encoding glutamine synthetase (GS) was identified by microarray-based hybridization using fiber mRNAs of allotetraploid Gossypium hirsutum, 7235, a super quality property germplasm line, and TM-1, a genetic standard in G. hirsutum. Northern-blot analysis verified transcript accumulation differences in 8 DPA fibers (including ovules) in the two varieties. The full-length cDNA encoding GS in 7235 was isolated and named GhGS. Sequence analysis revealed that the GhGS was similar to cytosolic GS. Southern-blot analysis showed that tetraploid cotton contained at least one copy of the A sub-genome and the D sub-genome. Genomic GhGS sequences were subsequently isolated from different varieties, TM-1, 7235 and two diploid progenitor cottons, G. herbaceum (A-genome) and G. raimondii (D-genome). Molecular mapping and single-marker analysis revealed that the GhGS was significantly correlated with fiber strength and was mapped to chromosome D7. Additionally, GS activities and total protein of the ovules and the fibers were assayed. The results showed a significantly higher GS activity in 7235 seeds compared to TM-1 seeds at 5 and 8 DPA. Also significant differences were found in total protein content and seed weight at 11 DPA. This suggested that GS promoted the seed-forming process by providing N. On the other hand, in fibers, GS activity and total protein assay indicated a lower total GS activity and longer fiber elongation period in 7235. These results suggest that the respective roles of the GS in ovules and fibers do not completely overlap.
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Affiliation(s)
- He Yajun
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, Cotton Research Institute, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, China
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A brief summary of major advances in cotton functional genomics and molecular breeding studies in China. ACTA ACUST UNITED AC 2007. [DOI: 10.1007/s11434-007-0500-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kandasamy MK, Burgos-Rivera B, McKinney EC, Ruzicka DR, Meagher RB. Class-specific interaction of profilin and ADF isovariants with actin in the regulation of plant development. THE PLANT CELL 2007; 19:3111-26. [PMID: 17933902 PMCID: PMC2174723 DOI: 10.1105/tpc.107.052621] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 09/06/2007] [Accepted: 09/24/2007] [Indexed: 05/20/2023]
Abstract
Two ancient and highly divergent actin-based cytoskeletal systems have evolved in angiosperms. Plant genomes encode complex actin and actin binding protein (ABP) gene families, most of which are phylogenetically grouped into gene classes with distinct vegetative or constitutive and reproductive expression patterns. In Arabidopsis thaliana, ectopic expression of high levels of a reproductive class actin, ACT1, in vegetative tissues causes severe dwarfing of plants with aberrant organization of most plant organs and cell types due to a severely altered actin cytoskeletal architecture. Overexpression of the vegetative class actin ACT2 to similar levels, however, produces insignificant phenotypic changes. We proposed that the misexpression of the pollen-specific ACT1 in vegetative cell types affects the dynamics of actin due to its inappropriate interaction with endogenous vegetative ABPs. To examine the functionally distinct interactions among the major classes of actins and ABPs, we ectopically coexpressed reproductive profilin (PRF4) or actin-depolymerizing factor (ADF) isovariants (e.g., ADF7) with ACT1. Our results demonstrated that the coexpression of these reproductive, but not vegetative, ABP isovariants suppressed the ectopic ACT1 expression phenotypes and restored wild-type stature and normal actin cytoskeletal architecture to the double transgenic plants. Thus, the actins and ABPs appear to have evolved class-specific, protein-protein interactions that are essential to the normal regulation of plant growth and development.
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Affiliation(s)
- Muthugapatti K Kandasamy
- Department of Genetics, Davison Life Sciences Building, University of Georgia, Athens, Georgia 30602, USA
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Tu LL, Zhang XL, Liang SG, Liu DQ, Zhu LF, Zeng FC, Nie YC, Guo XP, Deng FL, Tan JF, Xu L. Genes expression analyses of sea-island cotton (Gossypium barbadense L.) during fiber development. PLANT CELL REPORTS 2007; 26:1309-20. [PMID: 17377794 DOI: 10.1007/s00299-007-0337-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2006] [Revised: 01/26/2007] [Accepted: 02/27/2007] [Indexed: 05/14/2023]
Abstract
Sea-island cotton (Gossypium barbadense L.) is one of the most valuable cotton species due to its silkiness, luster, long staples, and high strength, but its fiber development mechanism has not been surveyed comprehensively. We constructed a normalized fiber cDNA library (from -2 to 25 dpa) of G. barbadense cv. Pima 3-79 (the genetic standard line) by saturation hybridization with genomic DNA. We screened Pima 3-79 fiber RNA from five developmental stages using a cDNA array including 9,126 plasmids randomly selected from the library, and we selected and sequenced 929 clones that had different signal intensities between any two stages. The 887 high-quality expressed sequence tags obtained were assembled into 645 consensus sequences (582 singletons and 63 contigs), of which 455 were assigned to functional categories using gene ontology. Almost 50% of binned genes belonged to metabolism functional categories. Based on subarray analysis of the 887 high-quality expressed sequence tags with 0-, 5-, 10-, 15-, and 20-dpa RNA of Pima 3-79 fibers and a mixture of RNA of nonfiber tissues, seven types of expression profiles were elucidated. Furthermore our results showed that phytohormones may play an important role in the fiber development.
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Affiliation(s)
- Li-Li Tu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070, China
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Chaudhry F, Guérin C, von Witsch M, Blanchoin L, Staiger CJ. Identification of Arabidopsis cyclase-associated protein 1 as the first nucleotide exchange factor for plant actin. Mol Biol Cell 2007; 18:3002-14. [PMID: 17538023 PMCID: PMC1949352 DOI: 10.1091/mbc.e06-11-1041] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2006] [Revised: 05/17/2007] [Accepted: 05/18/2007] [Indexed: 11/11/2022] Open
Abstract
The actin cytoskeleton powers organelle movements, orchestrates responses to abiotic stresses, and generates an amazing array of cell shapes. Underpinning these diverse functions of the actin cytoskeleton are several dozen accessory proteins that coordinate actin filament dynamics and construct higher-order assemblies. Many actin-binding proteins from the plant kingdom have been characterized and their function is often surprisingly distinct from mammalian and fungal counterparts. The adenylyl cyclase-associated protein (CAP) has recently been shown to be an important regulator of actin dynamics in vivo and in vitro. The disruption of actin organization in cap mutant plants indicates defects in actin dynamics or the regulated assembly and disassembly of actin subunits into filaments. Current models for actin dynamics maintain that actin-depolymerizing factor (ADF)/cofilin removes ADP-actin subunits from filament ends and that profilin recharges these monomers with ATP by enhancing nucleotide exchange and delivery of subunits onto filament barbed ends. Plant profilins, however, lack the essential ability to stimulate nucleotide exchange on actin, suggesting that there might be a missing link yet to be discovered from plants. Here, we show that Arabidopsis thaliana CAP1 (AtCAP1) is an abundant cytoplasmic protein; it is present at a 1:3 M ratio with total actin in suspension cells. AtCAP1 has equivalent affinities for ADP- and ATP-monomeric actin (Kd approximately 1.3 microM). Binding of AtCAP1 to ATP-actin monomers inhibits polymerization, consistent with AtCAP1 being an actin sequestering protein. However, we demonstrate that AtCAP1 is the first plant protein to increase the rate of nucleotide exchange on actin. Even in the presence of ADF/cofilin, AtCAP1 can recharge actin monomers and presumably provide a polymerizable pool of subunits to profilin for addition onto filament ends. In turnover assays, plant profilin, ADF, and CAP act cooperatively to promote flux of subunits through actin filament barbed ends. Collectively, these results and our understanding of other actin-binding proteins implicate CAP1 as a central player in regulating the pool of unpolymerized ATP-actin.
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Affiliation(s)
- Faisal Chaudhry
- *Department of Biological Sciences, Purdue University, West Lafayette, IN 47907-2064; and
| | - Christophe Guérin
- Institut de Recherches en Technologie et Sciences pour le Vivant (iRTSV), Commissariat à l'Energie Atomique/Centre National de la Recherche Scientifique/Institut National de la Recherche Agronomique/Université Joseph Fourier, Commissariat à l'Energie Atomique Grenoble, F38054 Grenoble, France
| | - Matthias von Witsch
- *Department of Biological Sciences, Purdue University, West Lafayette, IN 47907-2064; and
| | - Laurent Blanchoin
- Institut de Recherches en Technologie et Sciences pour le Vivant (iRTSV), Commissariat à l'Energie Atomique/Centre National de la Recherche Scientifique/Institut National de la Recherche Agronomique/Université Joseph Fourier, Commissariat à l'Energie Atomique Grenoble, F38054 Grenoble, France
| | - Christopher J. Staiger
- *Department of Biological Sciences, Purdue University, West Lafayette, IN 47907-2064; and
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Staiger CJ, Blanchoin L. Actin dynamics: old friends with new stories. CURRENT OPINION IN PLANT BIOLOGY 2006; 9:554-62. [PMID: 17011229 DOI: 10.1016/j.pbi.2006.09.013] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Accepted: 09/19/2006] [Indexed: 05/12/2023]
Abstract
Actin dynamics, or the rapid turnover of actin filaments, play a central role in numerous cellular processes. A large and diverse cast of characters, accessory proteins known as actin-binding proteins, modulate actin dynamics. They do this by binding to the monomer pool, interacting with the side and ends of filaments, creating breaks along a filament, and generating new filaments de novo. Recent biochemical and single-filament imaging analyses of several conserved classes of plant actin-binding proteins reveal unusual and unexpected properties. Examples that are highlighted in this review include: an abundant monomer-binding protein that catalyzes nucleotide exchange; a barbed-end capping protein that is dissociated from filament ends by the signaling lipid, phosphatidic acid; a villin-like bundling protein that lacks all Ca(2+)-regulated activities; and a formin family member that is non-processive and is sufficient to generate actin filament bundles. These and other stories motivate a careful description of the properties of plant proteins in vitro as a prelude to greater insight into the molecular mechanism(s) underlying the regulation of actin dynamics in vivo.
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Affiliation(s)
- Christopher J Staiger
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-2064, USA.
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Xu WL, Wang XL, Wang H, Li XB. Molecular characterization and expression analysis of nine cotton GhEF1A genes encoding translation elongation factor 1A. Gene 2006; 389:27-35. [PMID: 17107762 DOI: 10.1016/j.gene.2006.09.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 08/29/2006] [Accepted: 09/13/2006] [Indexed: 10/24/2022]
Abstract
The translation elongation factor 1A, eEF1A, plays an important role in protein synthesis, catalyzing the binding of aminoacyl-tRNA to the A-site of the ribosome by a GTP-dependent mechanism. To investigate the role of eEF1A for protein synthesis in cotton fiber development, nine different cDNA clones encoding eukaryotic translation elongation factor 1A were isolated from cotton (Gossypium hirsutum) fiber cDNA libraries. The isolated genes (cDNAs) were designated cotton elongation factor 1A gene GhEF1A1, GhEF1A2, GhEF1A3, GhEF1A4, GhEF1A5, GhEF1A6, GhEF1A7, GhEF1A8, GhEF1A9, respectively. They share high sequence homology at nucleotide level (71-99% identity) in the coding region and at amino acid level (96-99% identity) among each other. Phylogenetic analysis demonstrated that the nine GhEF1A genes can be divided into 5-6 subfamilies, indicating the divergence occurred in structures of the genes as well as the deduced proteins during evolution. Real-time quantitative RT-PCR analysis revealed that GhEF1A genes are differentially expressed in different tissues/organs. Of the nine GhEF1A genes, five are expressed at relatively high levels in young fibers. Further analysis indicated that expressions of the GhEF1As in fiber are highly developmental-regulated, suggesting that protein biosynthesis is very active at the early fiber elongation.
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Affiliation(s)
- Wen-Liang Xu
- College of Life Sciences, HuaZhong Normal University, Wuhan 430079, P.R. China
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Huang S, Gao L, Blanchoin L, Staiger CJ. Heterodimeric capping protein from Arabidopsis is regulated by phosphatidic acid. Mol Biol Cell 2006; 17:1946-58. [PMID: 16436516 PMCID: PMC1415281 DOI: 10.1091/mbc.e05-09-0840] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Revised: 12/13/2005] [Accepted: 01/17/2006] [Indexed: 11/11/2022] Open
Abstract
The cytoskeleton is a key regulator of morphogenesis, sexual reproduction, and cellular responses to extracellular stimuli. Changes in the cellular architecture are often assumed to require actin-binding proteins as stimulus-response modulators, because many of these proteins are regulated directly by binding to intracellular second messengers or signaling phospholipids. Phosphatidic acid (PA) is gaining widespread acceptance as a major, abundant phospholipid in plants that is required for pollen tube tip growth and mediates responses to osmotic stress, wounding, and phytohormones; however, the number of identified effectors of PA is rather limited. Here we demonstrate that exogenous PA application leads to significant increases in filamentous actin levels in Arabidopsis suspension cells and poppy pollen grains. To investigate further these lipid-induced changes in polymer levels, we analyzed the properties of a key regulator of actin filament polymerization, the heterodimeric capping protein from Arabidopsis thaliana (AtCP). AtCP binds to PA with a K(d) value of 17 muM and stoichiometry of approximately 1:2. It also binds well to PtdIns(4,5)P(2), but not to several other phosphoinositide or acidic phospholipids. The interaction with PA inhibited the actin-binding activity of CP. In the presence of PA, CP is unable to block the barbed or rapidly growing and shrinking end of actin filaments. Precapped filament barbed ends can also be uncapped by addition of PA, allowing rapid filament assembly from an actin monomer pool that is buffered with profilin. The findings support a model in which the inhibition of CP activity in cells by elevated PA results in the stimulation of actin polymerization from a large pool of profilin-actin. Such regulation may be important for the response of plant cells to extracellular stimuli as well as for the normal process of pollen tube tip growth.
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Affiliation(s)
- Shanjin Huang
- Department of Biological Sciences and The Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907-2064, USA
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