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Biswal AK, Soeno K, Gandla ML, Immerzeel P, Pattathil S, Lucenius J, Serimaa R, Hahn MG, Moritz T, Jönsson LJ, Israelsson-Nordström M, Mellerowicz EJ. Aspen pectate lyase PtxtPL1-27 mobilizes matrix polysaccharides from woody tissues and improves saccharification yield. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:11. [PMID: 24450583 PMCID: PMC3909318 DOI: 10.1186/1754-6834-7-11] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 01/07/2014] [Indexed: 05/02/2023]
Abstract
BACKGROUND Wood cell walls are rich in cellulose, hemicellulose and lignin. Hence, they are important sources of renewable biomass for producing energy and green chemicals. However, extracting desired constituents from wood efficiently poses significant challenges because these polymers are highly cross-linked in cell walls and are not easily accessible to enzymes and chemicals. RESULTS We show that aspen pectate lyase PL1-27, which degrades homogalacturonan and is expressed at the onset of secondary wall formation, can increase the solubility of wood matrix polysaccharides. Overexpression of this enzyme in aspen increased solubility of not only pectins but also xylans and other hemicelluloses, indicating that homogalacturonan limits the solubility of major wood cell wall components. Enzymatic saccharification of wood obtained from PL1-27-overexpressing trees gave higher yields of pentoses and hexoses than similar treatment of wood from wild-type trees, even after acid pretreatment. CONCLUSIONS Thus, the modification of pectins may constitute an important biotechnological target for improved wood processing despite their low abundance in woody biomass.
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Affiliation(s)
- Ajaya K Biswal
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S901 83 Umeå, Sweden
- Complex Carbohydrate Research Center, BioEnergy Science Center (BESC), University of Georgia, 315 Riverbend Rd, Athens, GA30602-4712 USA
| | - Kazuo Soeno
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S901 83 Umeå, Sweden
- Present address: National Agricultural Research Center for Western Region, National Agriculture and Food Research Organization (NARO), Zentsuji, Kagawa 765-8508 Japan
| | | | - Peter Immerzeel
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S901 83 Umeå, Sweden
| | - Sivakumar Pattathil
- Complex Carbohydrate Research Center, BioEnergy Science Center (BESC), University of Georgia, 315 Riverbend Rd, Athens, GA30602-4712 USA
| | - Jessica Lucenius
- Department of Physics, University of Helsinki, POB. 64FI-00014 Helsinki, Finland
| | - Ritva Serimaa
- Department of Physics, University of Helsinki, POB. 64FI-00014 Helsinki, Finland
| | - Michael G Hahn
- Complex Carbohydrate Research Center, BioEnergy Science Center (BESC), University of Georgia, 315 Riverbend Rd, Athens, GA30602-4712 USA
| | - Thomas Moritz
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S901 83 Umeå, Sweden
| | - Leif J Jönsson
- Department of Chemistry, Umeå University, S901 87 Umeå, Sweden
| | - Maria Israelsson-Nordström
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S901 83 Umeå, Sweden
| | - Ewa J Mellerowicz
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S901 83 Umeå, Sweden
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52
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Bohlmann H, Sobczak M. The plant cell wall in the feeding sites of cyst nematodes. FRONTIERS IN PLANT SCIENCE 2014; 5:89. [PMID: 24678316 PMCID: PMC3958752 DOI: 10.3389/fpls.2014.00089] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 02/24/2014] [Indexed: 05/19/2023]
Abstract
Plant parasitic cyst nematodes (genera Heterodera and Globodera) are serious pests for many crops. They enter the host roots as migratory second stage juveniles (J2) and migrate intracellularly toward the vascular cylinder using their stylet and a set of cell wall degrading enzymes produced in the pharyngeal glands. They select an initial syncytial cell (ISC) within the vascular cylinder or inner cortex layers to induce the formation of a multicellular feeding site called a syncytium, which is the only source of nutrients for the parasite during its entire life. A syncytium can consist of more than hundred cells whose protoplasts are fused together through local cell wall dissolutions. While the nematode produces a cocktail of cell wall degrading and modifying enzymes during migration through the root, the cell wall degradations occurring during syncytium development are due to the plants own cell wall modifying and degrading proteins. The outer syncytial cell wall thickens to withstand the increasing osmotic pressure inside the syncytium. Furthermore, pronounced cell wall ingrowths can be formed on the outer syncytial wall at the interface with xylem vessels. They increase the surface of the symplast-apoplast interface, thus enhancing nutrient uptake into the syncytium. Processes of cell wall degradation, synthesis and modification in the syncytium are facilitated by a variety of plant proteins and enzymes including expansins, glucanases, pectate lyases and cellulose synthases, which are produced inside the syncytium or in cells surrounding the syncytium.
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Affiliation(s)
- Holger Bohlmann
- Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life SciencesVienna, Austria
- *Correspondence: Holger Bohlmann, Division of Plant Protection, Department of Crop Sciences, University of Natural Resources and Life Sciences, UFT Tulln, Konrad Lorenz Str. 24, Vienna, 3430 Tulln, Austria e-mail:
| | - Miroslaw Sobczak
- Department of Botany, Warsaw University of Life SciencesWarsaw, Poland
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Qi X, Wu J, Wang L, Li L, Cao Y, Tian L, Dong X, Zhang S. Identifying the candidate genes involved in the calyx abscission process of 'Kuerlexiangli' (Pyrus sinkiangensis Yu) by digital transcript abundance measurements. BMC Genomics 2013; 14:727. [PMID: 24152304 PMCID: PMC4046677 DOI: 10.1186/1471-2164-14-727] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 10/18/2013] [Indexed: 11/25/2022] Open
Abstract
Background 'Kuerlexiangli’ (Pyrus sinkiangensis Yu), a native pear of Xinjiang, China, is an important agricultural fruit and primary export to the international market. However, fruit with persistent calyxes affect fruit shape and quality. Although several studies have looked into the physiological aspects of the calyx abscission process, the underlying molecular mechanisms remain unknown. In order to better understand the molecular basis of the process of calyx abscission, materials at three critical stages of regulation, with 6000 × Flusilazole plus 300 × PBO treatment (calyx abscising treatment) and 50 mg.L-1GA3 treatment (calyx persisting treatment), were collected and cDNA fragments were sequenced using digital transcript abundance measurements to identify candidate genes. Results Digital transcript abundance measurements was performed using high-throughput Illumina GAII sequencing on seven samples that were collected at three important stages of the calyx abscission process with chemical agent treatments promoting calyx abscission and persistence. Altogether more than 251,123,845 high quality reads were obtained with approximately 8.0 M raw data for each library. The values of 69.85%-71.90% of clean data in the digital transcript abundance measurements could be mapped to the pear genome database. There were 12,054 differentially expressed genes having Gene Ontology (GO) terms and associating with 251 Kyoto Encyclopedia of Genes and Genomes (KEGG) defined pathways. The differentially expressed genes correlated with calyx abscission were mainly involved in photosynthesis, plant hormone signal transduction, cell wall modification, transcriptional regulation, and carbohydrate metabolism. Furthermore, candidate calyx abscission-specific genes, e.g. Inflorescence deficient in abscission gene, were identified. Quantitative real-time PCR was used to confirm the digital transcript abundance measurements results. Conclusions We identified candidate genes that showed highly dynamic changes in expression during the calyx abscission process. These genes are potential targets for future functional characterization and should be valuable for exploration of the mechanisms of calyx abscission, and eventually for developing methods based on small molecule application to induce calyx abscission in fruit production. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-14-727) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Jun Wu
- College of Horticulture, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China.
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Genome-wide characterization of the Pectate Lyase-like (PLL) genes in Brassica rapa. Mol Genet Genomics 2013; 288:601-14. [PMID: 23999922 DOI: 10.1007/s00438-013-0775-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Accepted: 08/05/2013] [Indexed: 10/26/2022]
Abstract
Pectate lyases (PL) depolymerize demethylated pectin (pectate, EC 4.2.2.2) by catalyzing the eliminative cleavage of α-1,4-glycosidic linked galacturonan. Pectate Lyase-like (PLL) genes are one of the largest and most complex families in plants. However, studies on the phylogeny, gene structure, and expression of PLL genes are limited. To understand the potential functions of PLL genes in plants, we characterized their intron-exon structure, phylogenetic relationships, and protein structures, and measured their expression patterns in various tissues, specifically the reproductive tissues in Brassica rapa. Sequence alignments revealed two characteristic motifs in PLL genes. The chromosome location analysis indicated that 18 of the 46 PLL genes were located in the least fractionated sub-genome (LF) of B. rapa, while 16 were located in the medium fractionated sub-genome (MF1) and 12 in the more fractionated sub-genome (MF2). Quantitative RT-PCR analysis showed that BrPLL genes were expressed in various tissues, with most of them being expressed in flowers. Detailed qRT-PCR analysis identified 11 pollen specific PLL genes and several other genes with unique spatial expression patterns. In addition, some duplicated genes showed similar expression patterns. The phylogenetic analysis identified three PLL gene subfamilies in plants, among which subfamily II might have evolved from gene neofunctionalization or subfunctionalization. Therefore, this study opens the possibility for exploring the roles of PLL genes during plant development.
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55
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Mollet JC, Leroux C, Dardelle F, Lehner A. Cell Wall Composition, Biosynthesis and Remodeling during Pollen Tube Growth. PLANTS 2013; 2:107-47. [PMID: 27137369 PMCID: PMC4844286 DOI: 10.3390/plants2010107] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 02/19/2013] [Accepted: 02/19/2013] [Indexed: 01/01/2023]
Abstract
The pollen tube is a fast tip-growing cell carrying the two sperm cells to the ovule allowing the double fertilization process and seed setting. To succeed in this process, the spatial and temporal controls of pollen tube growth within the female organ are critical. It requires a massive cell wall deposition to promote fast pollen tube elongation and a tight control of the cell wall remodeling to modify the mechanical properties. In addition, during its journey, the pollen tube interacts with the pistil, which plays key roles in pollen tube nutrition, guidance and in the rejection of the self-incompatible pollen. This review focuses on our current knowledge in the biochemistry and localization of the main cell wall polymers including pectin, hemicellulose, cellulose and callose from several pollen tube species. Moreover, based on transcriptomic data and functional genomic studies, the possible enzymes involved in the cell wall remodeling during pollen tube growth and their impact on the cell wall mechanics are also described. Finally, mutant analyses have permitted to gain insight in the function of several genes involved in the pollen tube cell wall biosynthesis and their roles in pollen tube growth are further discussed.
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Affiliation(s)
- Jean-Claude Mollet
- Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale, EA4358, IRIB, Normandy University, University of Rouen, 76821 Mont Saint-Aignan, France.
| | - Christelle Leroux
- Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale, EA4358, IRIB, Normandy University, University of Rouen, 76821 Mont Saint-Aignan, France.
| | - Flavien Dardelle
- Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale, EA4358, IRIB, Normandy University, University of Rouen, 76821 Mont Saint-Aignan, France.
| | - Arnaud Lehner
- Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale, EA4358, IRIB, Normandy University, University of Rouen, 76821 Mont Saint-Aignan, France.
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Jiang J, Zhang Z, Cao J. Pollen wall development: the associated enzymes and metabolic pathways. PLANT BIOLOGY (STUTTGART, GERMANY) 2013; 15:249-63. [PMID: 23252839 DOI: 10.1111/j.1438-8677.2012.00706.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Accepted: 10/22/2012] [Indexed: 05/18/2023]
Abstract
Pollen grains are surrounded by a sculpted wall, which protects male gametophytes from various environmental stresses and microbial attacks, and also facilitates pollination. Pollen wall development requires lipid and polysaccharide metabolism, and some key genes and proteins that participate in these processes have recently been identified. Here, we summarise the genes and describe their functions during pollen wall development via several metabolic pathways. A working model involving substances and catalytic enzyme reactions that occur during pollen development is also presented. This model provides information on the complete process of pollen wall development with respect to metabolic pathways.
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Affiliation(s)
- J Jiang
- Laboratory of Cell & Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou, China
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Jiang J, Jiang J, Qiu L, Miao Y, Yao L, Cao J. Identification of gene expression profile during fertilization in Brassica campestris subsp. chinensis. Genome 2013; 56:39-48. [PMID: 23379337 DOI: 10.1139/gen-2012-0088] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fertilization is controlled by a complex gene regulatory network. To study the fertilization mechanism, we determined time courses of the four developmental stages of fertilization in Chinese cabbage pak-choi (Brassica campestris subsp. chinensis) by cytological observation. We then used the Arabidopsis ATH1 microarray to characterize the gene expression profiles of pollinated and unpollinated pistils in B. campestris subsp. chinensis. The result showed 44 up-regulated genes and 33 down-regulated genes in pollinated pistils compared with unpollinated pistils. Gene ontology analysis identified 20% of the up-regulated genes as belonging to the category of cell wall metabolism. We compared the up-regulated genes in pollinated pistils with previously identified pollen development related genes. Ten genes were found to be in common, which were termed as continuously expressed genes, in the two processes in the present article. Their expression patterns during pollen development and fertilization processes were then verified by RT-PCR. One of the continuously expressed genes, the homologous gene of At3g01270 in B. campestris subsp. chinensis, was confirmed as specifically expressed in microspores and pollinated pistils by using in situ hybridization. The potential biological functions of the other continuously expressed genes were also discussed.
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Affiliation(s)
- Jingjing Jiang
- a Laboratory of Cell and Molecular Biology, Institute of Vegetable Science, Zhejiang University, Hangzhou 310058, China
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Estornell LH, Agustí J, Merelo P, Talón M, Tadeo FR. Elucidating mechanisms underlying organ abscission. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2013; 199-200:48-60. [PMID: 23265318 DOI: 10.1016/j.plantsci.2012.10.008] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 10/03/2012] [Accepted: 10/31/2012] [Indexed: 05/19/2023]
Abstract
Abscission consists in the detachment of entire vegetative and reproductive organs due to cell separation processes occurring at the abscission zones (AZs) at specific positions of the plant body. From an evolutionary point of view, abscission is a highly advantageous process resulting into fruit and seed dispersal as well as the shedding of no longer useful organs. In an agricultural context, however, abscission may become a major limiting factor for crop productivity. Domestication of major crops included the selection of plants that did not naturally shed ripe fruits or seeds. The understanding of abscission is of great importance to control seed and fruit production and to improve breeding and harvesting practices. Thus, advances made on model plants and crops are of major importance since they may provide potential candidate genes for further biotechnological applications. Here, we review the current knowledge of the physiological, genetic and genomic aspects related to abscission including the most recently disclosed putative regulators that appear to be implicated in the development and/or activation of the AZs.
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Affiliation(s)
- Leandro H Estornell
- Institut Valencià d'Investigacions Agràries (IVIA), Centre de Genómica, Apartat Oficial, Montcada (València), Spain
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Hall H, Ellis B. Transcriptional programming during cell wall maturation in the expanding Arabidopsis stem. BMC PLANT BIOLOGY 2013; 13:14. [PMID: 23350960 PMCID: PMC3635874 DOI: 10.1186/1471-2229-13-14] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 01/21/2013] [Indexed: 05/18/2023]
Abstract
BACKGROUND Plant cell walls are complex dynamic structures that play a vital role in coordinating the directional growth of plant tissues. The rapid elongation of the inflorescence stem in the model plant Arabidopsis thaliana is accompanied by radical changes in cell wall structure and chemistry, but analysis of the underlying mechanisms and identification of the genes that are involved has been hampered by difficulties in accurately sampling discrete developmental states along the developing stem. RESULTS By creating stem growth kinematic profiles for individual expanding Arabidopsis stems we have been able to harvest and pool developmentally-matched tissue samples, and to use these for comparative analysis of global transcript profiles at four distinct phases of stem growth: the period of elongation rate increase, the point of maximum growth rate, the point of stem growth cessation and the fully matured stem. The resulting profiles identify numerous genes whose expression is affected as the stem tissues pass through these defined growth transitions, including both novel loci and genes identified in earlier studies. Of particular note is the preponderance of highly active genes associated with secondary cell wall deposition in the region of stem growth cessation, and of genes associated with defence and stress responses in the fully mature stem. CONCLUSIONS The use of growth kinematic profiling to create tissue samples that are accurately positioned along the expansion growth continuum of Arabidopsis inflorescence stems establishes a new standard for transcript profiling analyses of such tissues. The resulting expression profiles identify a substantial number of genes whose expression is correlated for the first time with rapid cell wall extension and subsequent fortification, and thus provide an important new resource for plant biologists interested in gene discovery related to plant biomass accumulation.
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Affiliation(s)
- Hardy Hall
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
- Currently: Swedish University of Agricultural Sciences (SLU), Umeå, 901 83, Sweden
| | - Brian Ellis
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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Abstract
To allow rhizobial infection of legume roots, plant cell walls must be locally degraded for plant-made infection threads (ITs) to be formed. Here we identify a Lotus japonicus nodulation pectate lyase gene (LjNPL), which is induced in roots and root hairs by rhizobial nodulation (Nod) factors via activation of the nodulation signaling pathway and the NIN transcription factor. Two Ljnpl mutants produced uninfected nodules and most infections arrested as infection foci in root hairs or roots. The few partially infected nodules that did form contained large abnormal infections. The purified LjNPL protein had pectate lyase activity, demonstrating that this activity is required for rhizobia to penetrate the cell wall and initiate formation of plant-made infection threads. Therefore, we conclude that legume-determined degradation of plant cell walls is required for root infection during initiation of the symbiotic interaction between rhizobia and legumes.
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Groszmann M, Paicu T, Alvarez JP, Swain SM, Smyth DR. SPATULA and ALCATRAZ, are partially redundant, functionally diverging bHLH genes required for Arabidopsis gynoecium and fruit development. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 68:816-29. [PMID: 21801252 DOI: 10.1111/j.1365-313x.2011.04732.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The Arabidopsis gynoecium is a complex organ that facilitates fertilization, later developing into a dehiscent silique that protects seeds until their dispersal. Identifying genes important for development is often hampered by functional redundancy. We report unequal redundancy between two closely related genes, SPATULA (SPT) and ALCATRAZ (ALC), revealing previously unknown developmental roles for each. SPT is known to support septum, style and stigma development in the flower, whereas ALC is involved in dehiscence zone development in the fruit. ALC diverged from a SPT-like ancestor following gene duplication coinciding with the At-β polyploidy event. Here we show that ALC is also involved in early gynoecium development, and SPT in later valve margin generation in the silique. Evidence includes the increased severity of early gynoecium disruption, and of later valve margin defects, in spt-alc double mutants. In addition, a repressive version of SPT (35S:SPT-SRDX) disrupts both structures. Consistent with redundancy, ALC and SPT expression patterns overlap in these tissues, and the ALC promoter carries two atypical E-box elements identical to one in SPT required for valve margin expression. Further, SPT can heterodimerize with ALC, and 35S:SPT can fully complement dehiscence defects in alc mutants, although 35S:ALC can only partly complement spt gynoecium disruptions, perhaps associated with its sequence simplification. Interactions with FRUITFULL and SHATTERPROOF genes differ somewhat between SPT and ALC, reflecting their different specializations. These two genes are apparently undergoing subfunctionalization, with SPT essential for earlier carpel margin tissues, and ALC specializing in later dehiscence zone development.
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MESH Headings
- Amino Acid Sequence
- Arabidopsis/genetics
- Arabidopsis/growth & development
- Arabidopsis/metabolism
- Arabidopsis Proteins/genetics
- Arabidopsis Proteins/metabolism
- Basic Helix-Loop-Helix Transcription Factors/genetics
- Basic Helix-Loop-Helix Transcription Factors/metabolism
- Chromosomes, Plant
- Conserved Sequence
- E-Box Elements
- Flowers/genetics
- Flowers/growth & development
- Flowers/ultrastructure
- Fruit/genetics
- Fruit/growth & development
- Gene Duplication
- Gene Expression Regulation, Plant
- Genes, Plant
- Genes, Reporter
- Genetic Complementation Test
- Microscopy, Electron, Scanning
- Molecular Sequence Data
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/growth & development
- Plants, Genetically Modified/metabolism
- Promoter Regions, Genetic
- Sequence Alignment
- Two-Hybrid System Techniques
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Affiliation(s)
- Michael Groszmann
- School of Biological Sciences, Monash University, Melbourne, Vic. 3800, Australia
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