liu.seSearch for publications in DiVA
Change search
Refine search result
1 - 11 of 11
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Edstam, Monika M.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Blomqvist, Kristina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Eklöf, Anna
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    Wennergren, Uno
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    Edqvist, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Coexpression patterns indicate that GPI-anchored non-specific lipid transfer proteins are involved in accumulation of cuticular wax, suberin and sporopollenin2013In: Plant Molecular Biology, ISSN 0167-4412, E-ISSN 1573-5028, Vol. 83, no 6, p. 625-649Article in journal (Refereed)
    Abstract [en]

    The non-specific lipid transfer proteins (nsLTP) are unique to land plants. The nsLTPs are characterized by a compact structure with a central hydrophobic cavity and can be classified to different types based on sequence similarity, intron position or spacing between the cysteine residues. The type G nsLTPs (LTPGs) have a GPI-anchor in the C-terminal region which attaches the protein to the exterior side of the plasma membrane. The function of these proteins, which are encoded by large gene families, has not been systematically investigated so far. In this study we have explored microarray data to investigate the expression pattern of the LTPGs in Arabidopsis and rice. We identified that the LTPG genes in each plant can be arranged in three expression modules with significant coexpression within the modules. According to expression patterns and module sizes, the Arabidopsis module AtI is functionally equivalent to the rice module OsI, AtII corresponds to OsII and AtIII is functionally comparable to OsIII. Starting from modules AtI, AtII and AtIII we generated extended networks with Arabidopsis genes coexpressed with the modules. Gene ontology analyses of the obtained networks suggest roles for LTPGs in the synthesis or deposition of cuticular waxes, suberin and sporopollenin. The AtI-module is primarily involved with cuticular wax, the AtII-module with suberin and the AtIII-module with sporopollenin. Further transcript analysis revealed that several transcript forms exist for several of the LTPG genes in both Arabidopsis and rice. The data suggests that the GPI-anchor attachment and localization of LTPGs may be controlled to some extent by alternative splicing.

  • 2.
    Edstam, Monika M.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Edqvist, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    GPI-anchored lipid transfer proteins are involved in the development of seed coats and pollen in ArabidopsisManuscript (preprint) (Other academic)
    Abstract [en]

    The non-specific lipid transfer proteins (nsLTPs) constitute a large protein family specific for plants. Proteins from the family are found in all land plants, but have not been identified in green algae. Their in vivo functions are still disputed although evidence is accumulating for a role of these proteins in cuticle development. In a previous study we performed a coexpression analysis of GPI-anchored nsLTPs (LTPGs) that suggested that these proteins also are involved in the accumulation of suberin and sporopollenin. Here, we follow up the previous co-expression study by characterising the phenotypes of Arabidopsis lines with insertions in LTPG genes. The observed phenotypes include an inability to limit tetrazolium salt uptake in seeds, development of hair-like structures on seeds, altered pollen morphologies and decreased levels of ω-hydroxy fatty acids in seed coats. The observed phenotypes give further support for a role in suberin and sporopollenin biosynthesis or deposition in Arabidopsis.

  • 3.
    Edstam, Monika M.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Laurila, Maiju
    Structural Bioinformatics Laboratory, Department of Biosciences, Åbo Akademi University, Turku, Finland.
    Höglund, Andrey
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Raman, Amitha
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Dahlström, Käthe M.
    Structural Bioinformatics Laboratory, Department of Biosciences, Åbo Akademi University, Turku, Finland.
    Salminen, Tiina A.
    Structural Bioinformatics Laboratory, Department of Biosciences, Åbo Akademi University, Turku, Finland.
    Edqvist, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Blomqvist, Kristina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Characterization of GPI-anchored lipid transfer proteins in Physcomitrella patens2014In: Plant physiology and biochemistry (Paris), ISSN 0981-9428, E-ISSN 1873-2690, Vol. 75, p. 55-69Article in journal (Refereed)
    Abstract [en]

    The non-specific lipid transfer proteins (nsLTPs) are characterized by a compact structure with a central hydrophobic cavity very suitable for binding hydrophobic ligands, such as lipids. The nsLTPs are encoded by large gene families in all land plant lineages, but seem to be absent from green algae. The nsLTPs are classified to different types based on molecular weight, sequence similarity, intron position or spacing between the cysteine residues. The Type G nsLTPs (LTPGs) have a GPI-anchor in the C-terminal region which may attach the protein to the exterior side of the plasma membrane. Here, we present the first characterization of nsLTPs from an early diverged plant, the moss Physcomitrella patens. Physcomitrella LTPGs were heterologously produced and purified from Pichia pastoris. The purified moss LTPGs were found to be extremely heat stable and showed a binding preference for unsaturated fatty acids. Expression of a moss LTPG-YFP fusion revealed localization to the plasma membrane. The expression of many of the moss LTPGs were found to be upregulated during drought and cold treatments. Lipid profiling revealed that cutin monomers, such as C16 and C18 mono- and di-hydroxylated fatty acids, could be identified in Physcomitrella.

  • 4.
    Edstam, Monika M.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics. Linköping University, The Institute of Technology.
    Viitanen, Lenita
    Abo Akad University.
    Salminen, Tiina A.
    Abo Akad University.
    Edqvist, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics.
    Evolutionary History of the Non-Specific Lipid Transfer Proteins2011In: MOLECULAR PLANT, ISSN 1674-2052, Vol. 4, no 6, p. 947-964Article in journal (Refereed)
    Abstract [en]

    The non-specific lipid transfer proteins (nsLTPs) are small, basic proteins characterized by a tunnel-like hydrophobic cavity, capable of transferring various lipid molecules between lipid bilayers. Most nsLTPs are synthesized with an N-terminal signal peptide that localizes the protein to the apoplastic space. The nsLTPs have only been identified in seed plants, where they are encoded by large gene families. We have initiated an analysis of the evolutionary history of the nsLTP family using genomic and EST information from non-seed land plants and green algae to determine: (1) when the nsLTP family arose, (2) how often new nsLTP subfamilies have been created, and (3) how subfamilies differ in their patterns of expansion and loss in different plant lineages. In this study, we searched sequence databases and found that genes and transcripts encoding nsLTPs are abundant in liverworts, mosses, and all other investigated land plants, but not present in any algae. The tertiary structures of representative liverwort and moss nsLTPs were further studied with homology modeling. The results indicate that the nsLTP family has evolved after plants conquered land. Only two of the four major subfamilies of nsLTPs found in flowering plants are present in mosses and liverworts. The additional subfamilies have arisen later, during land plant evolution. In this report, we also introduce a modified nsLTP classification system.

  • 5.
    Kumar, RM Saravana
    et al.
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Gao, Liu Xiao
    Laboratory of Fruit Quality Biology, Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Hangzhou, China.
    Yuan, Hu Wei
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Xu, Dong Bin
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Liang, Zhao
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Tao, Shen Chen
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Guo, Wen Bin
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Yan, Dao Liang
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Zheng, Bing Song
    State Key Laboratory for Subtropical Silviculture, Zhejiang A and F University, Linan, China.
    Edqvist, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Auxin enhances grafting success in Carya cathayensis (Chinese hickory)2018In: Planta, ISSN 0032-0935, E-ISSN 1432-2048, Vol. 247, no 3, p. 761-772Article in journal (Refereed)
    Abstract [en]

    Main conclusion

    Application of auxin to root stock and scion increases the success rate of grafting in Chinese hickory.

    The nuts of the Chinese hickory (Carya cathayensis) tree are considered both delicious and healthy. The popularity and high demand result is that the hickory nuts are of very high economical value for horticulture. This is particularly true for the Zhejiang province in eastern China where this tree is widely cultivated. However, there are several difficulties surrounding the hickory cultivation, such as for example long vegetative growth, tall trees, labour-intensive nut picking, and slow variety improvements. These complications form a great bottleneck in the expansion of the hickory industry. The development of an efficient grafting procedure could surpass at least some of these problems. In this study, we demonstrate that application of the auxin indole-3-acetic acid promotes the grafting process in hickory, whereas application of the auxin transport inhibitor 1-N-naphthylphthalamic acid inhibits the grafting process. Furthermore, we have identified hickory genes in the PINABCB, and AUX/LAX-families known to encode influx and efflux carriers in the polar transport of auxin. We show that increased expression of several of these genes, such as CcPIN1b and CcLAX3, is correlating with successful grafting.

  • 6.
    Leijon, Matti W.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics. Linköping University, The Institute of Technology.
    Hagenblad, Jenny
    Uppsala University.
    Edqvist, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics. Linköping University, The Institute of Technology.
    Karlsson Strese, Else-Marie
    Swedish Museum of Cultural History.
    DNA preservation and utility of a historic seed collection2009In: Seed Science Research, ISSN 0960-2585, E-ISSN 1475-2735, Vol. 19, p. 125-135Article in journal (Refereed)
    Abstract [en]

    Historic collections of biological material are important genetic resources for taxonomic, evolutionary and historical research. In this paper we describe a seed collection dating from 1862 to 1918 maintained at the Swedish Museum of Cultural History. The collection contains over 3000 well-documented seed samples of various agricultural crops, mostly cereals. A subset of 100 samples divided over ten species frequently represented in the collection and a range of ages were tested for germinability and DNA preservation. None of these accessions were found to contain viable seeds. DNA extracted from the seeds was degraded, but the amount of degradation varied between species. DNA quality was evaluated by yield, fragment size and size of amplification product. Quality was highest for DNA extracted from Pisum sativum and Vicia sativa. DNA extracted from Brassica napus, Beta vulgaris and Trifolium pratense was more fragmented, and DNA extracted from Triticum aestivum, Secale sereale, Hordeum vulgare, Avena sativa and Phleum pratense was most degraded. Polymerase chain reaction (PCR) amplification of ribosomal DNA fragments of up to 700 bp was permitted for most samples in all species. To test whether single-copy nuclear genes could be amplified from the extracted DNA, microsatellite markers were used on the Pisum sativum and Hordeum vulgare samples. Polymorphisms of microsatellite markers were detected between samples for both species. The results show that the 19th-century seed collection can be utilized to infer genetic relationships among obsolete cultivars as well as for other types of genetic research based on sequence or marker analysis.

  • 7.
    Leino, Matti
    et al.
    Swedish Museum of Cultural History, Julita.
    Edqvist, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics . Linköping University, The Institute of Technology.
    Germination of 151-year old Acacia spp. seeds2010In: Genetic Resources and Crop Evolution, ISSN 0925-9864, E-ISSN 1573-5109, Vol. 57, no 5, p. 741-746Article in journal (Refereed)
    Abstract [en]

    A collection of seeds from five Acacia species was made in Egypt in 1856. Since then, the seeds have been stored at room temperature in different Swedish museums. Due to the extreme longevity within the seeds of Acacia and related species, germination tests were performed on the now 151-year old seed. Seeds of two of the five species tested germinated. The first, Acacia farnesiana (L.) Willd., had two seeds germinate, and Acacia melanoxylon R. Br. ex Ait. f. had one seed germinate. In addition, DNA was extracted from the aged seed and DNA preservation was analyzed. Four of the tested species displayed well preserved DNA, whereas DNA from Albizia lebbeck (L.) Benth. showed signs of degradation. The 151-year longevity of the Acacia seeds is among the longest of dry-stored seeds reported. Several independent studies now report on extreme survival capacity for Acacia and related genera suggesting that these genera are suitable for studies on the characteristics of seeds with long storage performance. The results also demonstrate that herbaria and seed collections stored in museums and institutional depositories can be alternate sources of plants genetic material and should be given conservation attention.

  • 8.
    Malmbecker Edstam, Monika
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Edqvist, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Involvement of GPI-anchored lipid transfer proteins in the development of seed coats and pollen in Arabidopsis thaliana2014In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 152, no 1, p. 32-42Article in journal (Refereed)
    Abstract [en]

    The non-specific lipid transfer proteins (nsLTPs) constitute a large protein family specific for plants. Proteins from the family are found in all land plants but have not been identified in green algae. Their in vivo functions are still disputed although evidence is accumulating for a role of these proteins in cuticle development. In a previous study, we performed a co-expression analysis of glycosylphosphatidylinositol (GPI)-anchored nsLTPs (LTPGs), which suggested that these proteins are also involved in the accumulation of suberin and sporopollenin. Here, we follow up the previous co-expression study by characterizing the phenotypes of Arabidopsis thaliana lines with insertions in LTPG genes. The observed phenotypes include an inability to limit tetrazolium salt uptake in seeds, development of hair-like structures on seeds, altered pollen morphologies and decreased levels of ω-hydroxy fatty acids in seed coats. The observed phenotypes give further support for a role in suberin and sporopollenin biosynthesis or deposition in A. thaliana.

  • 9.
    Viitanen, Lenita
    et al.
    Department of Biochemistry and Pharmacy ° bo Akademi University, Turku, Finland.
    Nylund, Matts
    Department of Biochemistry and Pharmacy ° bo Akademi University, Turku, Finland.
    Eklund, D. Magnus
    Department of Plant Biology and Forest Genetics Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Alm, Christina
    Department of Plant Biology and Forest Genetics Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Eriksson, Ann-Katrin
    Department of Plant Biology and Forest Genetics Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Tuuf, Jessica
    Department of Biochemistry and Pharmacy A ° bo Akademi University, Turku, Finland.
    Salminen, Tiina A.
    Department of Biochemistry and Pharmacy ° bo Akademi University, Turku, Finland.
    Mattjus, Peter
    Department of Biochemistry and Pharmacy ° bo Akademi University, Turku, Finland.
    Edqvist, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Characterization of SCP-2 from Euphorbia lagascae reveals that a single Leu/Met exchange enhances sterol transfer activity2006In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 273, p. 5641-5655Article in journal (Refereed)
    Abstract [en]

    Sterol carrier protein-2 (SCP-2) is a small intracellular basic protein domain implicated in peroxisomal beta-oxidation. We extend our knowledge of plant SCP-2 by characterizing SCP-2 from Euphorbia lagascae. This protein consists of 122 amino acids including a PTS1 peroxisomal targeting signal. It has a molecular mass of 13.6 kDa and a pI of 9.5. It shares 67% identity and 84% similarity with SCP-2 from Arabidopsis thaliana. Proteomic analysis revealed that E. lagascae SCP-2 accumulates in the endosperm during seed germination. It showed in vitro transfer activity of BODIPY-phosphatidylcholine (BODIPY-PC). The transfer of BODIPY-PC was almost completely inhibited after addition of phosphatidylinositol, palmitic acid, stearoyl-CoA and vernolic acid, whereas sterols only had a very marginal inhibitory effect. We used protein modelling and site-directed mutagenesis to investigate why the BODIPY-PC transfer mediated by E. lagascae SCP-2 is not sensitive to sterols, whereas the transfer mediated by A. thaliana SCP-2 shows sterol sensitivity. Protein modelling suggested that the ligand-binding cavity of A. thaliana SCP-2 has four methionines (Met12, 14, 15 and 100), which are replaced by leucines (Leu11, 13, 14 and 99) in E. lagascae SCP-2. Changing Leu99 to Met99 was sufficient to convert E. lagascae SCP-2 into a sterol-sensitive BODIPY-PC-transfer protein, and correspondingly, changing Met100 to Leu100 abolished the sterol sensitivity of A. thaliana SCP-2.

  • 10. West, Gun
    et al.
    Viitanen, Lenita
    Alm, Christina
    Mattjus, Peter
    Salminen, Tiina A.
    Edqvist, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics .
    Identification of a glycosphingolipid transfer protein GLTP1 in Arabidopsis thaliana2008In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 275, no 13, p. 3421-3437Article in journal (Refereed)
    Abstract [en]

    Arabidopsis thaliana At2g33470 encodes a glycolipid transfer protein (GLTP) that enhances the intervesicular trafficking of glycosphingolipids in vitro. GLTPs have previously been identified in animals and fungi but not in plants. Thus, At2g33470 is the first identified plant GLTP and we have designated it AtGTLP1. AtGLTP1 transferred BODIPY-glucosylceramide at a rate of 0.7 pmol·s-1, but BODIPY-galactosylceramide and BODIPY-lactosylceramide were transferred slowly, with rates below 0.1 pmol·s-1. AtGLTP1 did not transfer BODIPY-sphingomyelin, monogalactosyldiacylglycerol or digalactosyldiacylglycerol. The human GLTP transfers BODIPY-glucosylceramide, BODIPY-galactosylceramide and BODIPY-lactosylceramide with rates greater than 0.8 pmol·s-1. Structural models showed that the residues that are most critical for glycosphingolipid binding in human GLTP are conserved in AtGLTP1, but some of the sugar-binding residues are unique, and this provides an explanation for the distinctly different transfer preferences of AtGLTP1 and human GLTP. The AtGLTP1 variant Arg59Lys/Asn95Leu showed low BODIPY-glucosylceramide transfer activity, indicating that Arg59 and/or Asn95 are important for the specific binding of glucosylceramide to AtGLTP1. We also show that, in A. thaliana, AtGLTP1 together with At1g21360 and At3g21260 constitute a small gene family orthologous to the mammalian GLTPs. However, At1g21360 and At3g21260 did not transfer any of the tested lipids in vitro. © 2008 The Authors.

  • 11. Zheng, Bing Song
    et al.
    Rönnberg, Elin
    Viitanen, Lenita
    Salminen, Tiina A.
    Lundgren, Krister
    Moritz, Thomas
    Edqvist, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Molecular genetics .
    Arabidopsis sterol carrier protein-2 is required for normal development of seeds and seedlings2008In: Journal of Experimental Botany, ISSN 0022-0957, E-ISSN 1460-2431, Vol. 59, no 12, p. 3485-3499Article in journal (Refereed)
    Abstract [en]

    The Arabidopsis thaliana sterol carrier protein-2 (AtSCP2) is a small, basic and peroxisomal protein that in vitro enhances the transfer of lipids between membranes. AtSCP2 and all other plant SCP-2 that have been identified are single-domain polypeptides, whereas in many other eukaryotes SCP-2 domains are expressed in the terminus of multidomain polypeptides. The AtSCP2 transcript is expressed in all analysed tissues and developmental stages, with the highest levels in floral tissues and in maturing seeds. The expression of AtSCP2 is highly correlated with the multifunctional protein-2 (MFP2) involved in β-oxidation. A. thaliana Atscp2-1 plants deficient in AtSCP2 show altered seed morphology, a delayed germination, and are dependent on an exogenous carbon source to avoid a delayed seedling establishment. Metabolomic investigations revealed 110 variables (putative metabolites) that differed in relative concentration between Atscp2-1 and normal A. thaliana wild-type seedlings. Microarray analysis revealed that many genes whose expression is altered in mutants with a deficiency in the glyoxylate pathway, also have a changed expression level in Atscp2-1. © 2008 The Author(s).

1 - 11 of 11
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf