Anja Fuglsang | University of Copenhagen (original) (raw)
Papers by Anja Fuglsang
Methods in molecular biology, Nov 29, 2023
Plant Signaling & Behavior, Jul 1, 2011
The Plant Cell, Apr 1, 2010
The plasma membrane H +-ATPase (PM H +-ATPase) plays an important role in the regulation of ion a... more The plasma membrane H +-ATPase (PM H +-ATPase) plays an important role in the regulation of ion and metabolite transport and is involved in physiological processes that include cell growth, intracellular pH, and stomatal regulation. PM H +-ATPase activity is controlled by many factors, including hormones, calcium, light, and environmental stresses like increased soil salinity. We have previously shown that the Arabidopsis thaliana Salt Overly Sensitive2-Like Protein Kinase5 (PKS5) negatively regulates the PM H +-ATPase. Here, we report that a chaperone, J3 (DnaJ homolog 3; heat shock protein 40-like), activates PM H +-ATPase activity by physically interacting with and repressing PKS5 kinase activity. Plants lacking J3 are hypersensitive to salt at high external pH and exhibit decreased PM H +-ATPase activity. J3 functions upstream of PKS5 as double mutants generated using j3-1 and several pks5 mutant alleles with altered kinase activity have levels of PM H +-ATPase activity and responses to salt at alkaline pH similar to their corresponding pks5 mutant. Taken together, our results demonstrate that regulation of PM H +-ATPase activity by J3 takes place via inactivation of the PKS5 kinase.
Journal of Integrative Plant Biology, Jan 12, 2022
The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and deve... more The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and development. It is an important factor in response to abiotic and biotic stresses and is subject to tight regulation. We are in demand for new sustainable natural growth regulators and as a key enzyme for regulation of transport into the plant cell the PM H+‐ATPase is a potential target for these. In this review, we have evaluated the known non‐protein natural compounds with regulatory effects on the PM H+‐ATPase, focusing on their mechanism of action and their potential as biologicals/growth regulators in plant production of future sustainable agriculture.
Journal of Integrative Plant Biology, 2022
The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and deve... more The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and development. It is an important factor in response to abiotic and biotic stresses and is subject to tight regulation. We are in demand for new sustainable natural growth regulators and as a key enzyme for regulation of transport into the plant cell the PM H+‐ATPase is a potential target for these. In this review, we have evaluated the known non‐protein natural compounds with regulatory effects on the PM H+‐ATPase, focusing on their mechanism of action and their potential as biologicals/growth regulators in plant production of future sustainable agriculture.
Molecular Oncology, Apr 28, 2023
Tissue inhibitor of metalloproteinases‐1 (TIMP‐1) regulates the proteolytic activity of matrix me... more Tissue inhibitor of metalloproteinases‐1 (TIMP‐1) regulates the proteolytic activity of matrix metalloproteinases (MMPs), playing an important role in the homeostasis of the extracellular matrix. Beyond its well‐known role in tissue maintenance, TIMP‐1 has been associated with multiple MMP‐independent cytokine‐like functions. The protein structure of TIMP‐1, with two distinct domains, one interacting with MMPs and another able to bind multiple partners, provides a rationale for this multifunctionality. The identification of CD63 as a cell surface receptor for TIMP‐1, able to mediate intracellular signaling through the Erk/MAPK axis, provided a molecular basis for the role of TIMP‐1 in cellular signaling. However, several lines of evidence suggest that TIMP‐1 may be able to associate with many interaction partners, thus attaining multiple functions. To enable the identification of previously unknown interaction partners that may underpin the core cellular functions of TIMP‐1, known as well as unknown, we performed a yeast two‐hybrid screening using a mammary gland complementary DNA (cDNA) library. We report here the identification of multiple interactors, including MHC class II‐associated invariant chain γ (CD74). We verified that CD74 interacts with TIMP‐1 in breast cancer cells and that this interaction contributes to cellular internalization of TIMP‐1 and mediates intracellular signaling through the Akt signaling axis in breast cancer cells. These data provide new insights into the complex nature of the functions of TIMP‐1 and their potential mechanistic basis.
Plant physiology, Dec 21, 2016
While the importance of cell-type specificity in plant adaptive responses is widely accepted, onl... more While the importance of cell-type specificity in plant adaptive responses is widely accepted, only a limited number of studies have addressed this issue at the functional level. We have combined electrophysiological, imaging, and biochemical techniques to reveal physiological mechanisms conferring higher sensitivity of apical root cells to salinity in barley. We show that salinity application to the root apex arrests root growth in a highly tissue- and treatment-specific manner. Although salinity-induced transient net Na+ uptake was about 4-fold higher in the root apex compared with the mature zone, mature root cells accumulated more cytosolic and vacuolar Na+ suggesting that higher sensitivity of apical cells to salt is not related to either enhanced Na+ exclusion or sequestration inside the root. Rather, the above differential sensitivity between the two zones originates from a 10-fold difference in K+ efflux between the mature zone and the apical region (much poorer in the root a...
Communications Biology
Plasma membrane (PM) H+-ATPases are the electrogenic proton pumps that export H+ from plant and f... more Plasma membrane (PM) H+-ATPases are the electrogenic proton pumps that export H+ from plant and fungal cells to acidify the surroundings and generate a membrane potential. Plant PM H+-ATPases are equipped with a C‑terminal autoinhibitory regulatory (R) domain of about 100 amino acid residues, which could not be identified in the PM H+-ATPases of green algae but appeared fully developed in immediate streptophyte algal predecessors of land plants. To explore the physiological significance of this domain, we created in vivo C-terminal truncations of autoinhibited PM H+‑ATPase2 (AHA2), one of the two major isoforms in the land plant Arabidopsis thaliana. As more residues were deleted, the mutant plants became progressively more efficient in proton extrusion, concomitant with increased expansion growth and nutrient uptake. However, as the hyperactivated AHA2 also contributed to stomatal pore opening, which provides an exit pathway for water and an entrance pathway for pests, the mutant p...
<p>Curcumin (Sigma-Aldrich) was initially identified as a hit in an <i>in vitro</i... more <p>Curcumin (Sigma-Aldrich) was initially identified as a hit in an <i>in vitro</i> screen for inhibitors of the plasma membrane H<sup>+</sup>-ATPase. Curcumin (CM, <b>1</b>) demethoxycurcumin (DMCM, <b>2</b>), bisdemethoxycurcumin (BDCM, <b>3</b>) and 1,5-dihydroxy-1,7-bis(4-hydroxy-3-methoxyphenyl)-4,6-heptadien-3-one (<b>6</b>) were then purified as previous described [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163260#pone.0163260.ref039" target="_blank">39</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163260#pone.0163260.ref062" target="_blank">62</a>]. 6-shogaol (<b>4</b>) and dibenzylideneacetone (<b>9</b>) were obtained from Sigma-Aldrich. Tetrahydrocurcumin (<b>5</b>), 1,7-bis(3',4'-dimethoxyphenyl)-4,4-dimethyl-1,6-heptadien-3,5-dione (<b>7</b>) and 1-(3',4'-dimethoxyphenyl)-4,4-dimethyl-7-(4'-methoxyphenyl)-1,6-heptadien-3,5-dione (<b>8</b>) were synthesized as previously described in the literature[<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163260#pone.0163260.ref063" target="_blank">63</a>].</p
Perspectives for using genetically encoded fluorescent
Plant Physiology, 2021
Plant plasma membrane H+-ATPases and Ca2+-ATPases maintain low cytoplasmic concentrations of H+ a... more Plant plasma membrane H+-ATPases and Ca2+-ATPases maintain low cytoplasmic concentrations of H+ and Ca2+, respectively, and are essential for plant growth and development. These low concentrations allow plasma membrane H+-ATPases to function as electrogenic voltage stats, and Ca2+-ATPases as “off” mechanisms in Ca2+-based signal transduction. Although these pumps are autoregulated by cytoplasmic concentrations of H+ and Ca2+, respectively, they are also subject to exquisite regulation in response to biotic and abiotic events in the environment. A common paradigm for both types of pumps is the presence of terminal regulatory (R) domains that function as autoinhibitors that can be neutralized by multiple means, including phosphorylation. A picture is emerging in which some of the phosphosites in these R domains appear to be highly, nearly constantly phosphorylated, whereas others seem to be subject to dynamic phosphorylation. Thus, some sites might function as major switches, whereas ...
![Research paper thumbnail of Cover Feature: LEGO-Inspired Drug Design: Unveiling a Class of Benzo[d ]thiazoles Containing a 3,4-Dihydroxyphenyl Moiety as Plasma Membrane H+ -ATPase Inhibitors (ChemMedChem 1/2018)](https://attachments.academia-assets.com/105276036/thumbnails/1.jpg)
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](ChemMedChem, Jan 15, 2017
The fungal plasma membrane H+ -ATPase (Pma1p) is a potential target for the discovery of new anti... more The fungal plasma membrane H+ -ATPase (Pma1p) is a potential target for the discovery of new antifungal agents. Surprisingly, no structure-activity relationship studies for small molecules targeting Pma1p have been reported. Herein, we disclose a LEGO-inspired fragment assembly strategy for the design, synthesis, and discovery of benzo[d]thiazoles containing a 3,4-dihydroxyphenyl moiety as potential Pma1p inhibitors. A series of 2-(benzo[d]thiazol-2-ylthio)-1-(3,4-dihydroxyphenyl)ethanones was found to inhibit Pma1p, with the most potent IC50 value of 8 μm in an in vitro plasma membrane H+ -ATPase assay. These compounds were also found to strongly inhibit the action of proton pumping when Pma1p was reconstituted into liposomes. 1-(3,4-Dihydroxyphenyl)-2-((6-(trifluoromethyl)benzo[d]thiazol-2-yl)thio)ethan-1-one (compound 38) showed inhibitory activities on the growth of Candida albicans and Saccharomyces cerevisiae, which could be correlated and substantiated with the ability to inh...
Biophysical Journal, 2014
We have used time-resolved fluorescenceresonance energy transfer (TR-FRET) to study the structura... more We have used time-resolved fluorescenceresonance energy transfer (TR-FRET) to study the structural basis of regulation of sarcoplasmic reticulum Ca 2þ ATPase (SERCA) by a single-pass transmembrane protein, phospholamban (PLB). SERCA actively sequesters Ca 2þ back into the sarcoplasmic reticulum to cause muscle relaxation. In the heart, SERCA is inhibited by unphosphorylated PLB. Physiologically, this inhibition is relieved by either micromolar Ca 2þ or phosphorylation of PLB. Dysregulation of SERCA-PLB complex causes Ca 2þ mishandling in cardiomyocyte, which is a prominent feature in heart failure. Our goal is to elucidate the structural basis for the regulation of the complex, with an emphasis on the structural rearrangement during relief of inhibition. We have used time-resolved fluorescence resonance energy transfer (TR-FRET) to probe the complex directly by measuring the distances between SERCA (C674) and a series of positions on PLB in co-reconstituted vesicles. Our data supports that the cytoplasmic domain of bound PLB exists in two states. The relief of inhibition is achieved by combined effect of dissociation of the complex and shifting the equilibrium of the two states of bound PLB. Spectroscopy was performed in the Biophysical Spectroscopy Center at the University of Minnesota. This work was funded by NIH grants to DDT (R01 GM27906 and P30 AR0507220).
Plant Signaling & Behavior, 2011
Methods in molecular biology, Nov 29, 2023
Plant Signaling & Behavior, Jul 1, 2011
The Plant Cell, Apr 1, 2010
The plasma membrane H +-ATPase (PM H +-ATPase) plays an important role in the regulation of ion a... more The plasma membrane H +-ATPase (PM H +-ATPase) plays an important role in the regulation of ion and metabolite transport and is involved in physiological processes that include cell growth, intracellular pH, and stomatal regulation. PM H +-ATPase activity is controlled by many factors, including hormones, calcium, light, and environmental stresses like increased soil salinity. We have previously shown that the Arabidopsis thaliana Salt Overly Sensitive2-Like Protein Kinase5 (PKS5) negatively regulates the PM H +-ATPase. Here, we report that a chaperone, J3 (DnaJ homolog 3; heat shock protein 40-like), activates PM H +-ATPase activity by physically interacting with and repressing PKS5 kinase activity. Plants lacking J3 are hypersensitive to salt at high external pH and exhibit decreased PM H +-ATPase activity. J3 functions upstream of PKS5 as double mutants generated using j3-1 and several pks5 mutant alleles with altered kinase activity have levels of PM H +-ATPase activity and responses to salt at alkaline pH similar to their corresponding pks5 mutant. Taken together, our results demonstrate that regulation of PM H +-ATPase activity by J3 takes place via inactivation of the PKS5 kinase.
Journal of Integrative Plant Biology, Jan 12, 2022
The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and deve... more The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and development. It is an important factor in response to abiotic and biotic stresses and is subject to tight regulation. We are in demand for new sustainable natural growth regulators and as a key enzyme for regulation of transport into the plant cell the PM H+‐ATPase is a potential target for these. In this review, we have evaluated the known non‐protein natural compounds with regulatory effects on the PM H+‐ATPase, focusing on their mechanism of action and their potential as biologicals/growth regulators in plant production of future sustainable agriculture.
Journal of Integrative Plant Biology, 2022
The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and deve... more The plant plasma membrane (PM) H+‐ATPase is an essential enzyme controlling plant growth and development. It is an important factor in response to abiotic and biotic stresses and is subject to tight regulation. We are in demand for new sustainable natural growth regulators and as a key enzyme for regulation of transport into the plant cell the PM H+‐ATPase is a potential target for these. In this review, we have evaluated the known non‐protein natural compounds with regulatory effects on the PM H+‐ATPase, focusing on their mechanism of action and their potential as biologicals/growth regulators in plant production of future sustainable agriculture.
Molecular Oncology, Apr 28, 2023
Tissue inhibitor of metalloproteinases‐1 (TIMP‐1) regulates the proteolytic activity of matrix me... more Tissue inhibitor of metalloproteinases‐1 (TIMP‐1) regulates the proteolytic activity of matrix metalloproteinases (MMPs), playing an important role in the homeostasis of the extracellular matrix. Beyond its well‐known role in tissue maintenance, TIMP‐1 has been associated with multiple MMP‐independent cytokine‐like functions. The protein structure of TIMP‐1, with two distinct domains, one interacting with MMPs and another able to bind multiple partners, provides a rationale for this multifunctionality. The identification of CD63 as a cell surface receptor for TIMP‐1, able to mediate intracellular signaling through the Erk/MAPK axis, provided a molecular basis for the role of TIMP‐1 in cellular signaling. However, several lines of evidence suggest that TIMP‐1 may be able to associate with many interaction partners, thus attaining multiple functions. To enable the identification of previously unknown interaction partners that may underpin the core cellular functions of TIMP‐1, known as well as unknown, we performed a yeast two‐hybrid screening using a mammary gland complementary DNA (cDNA) library. We report here the identification of multiple interactors, including MHC class II‐associated invariant chain γ (CD74). We verified that CD74 interacts with TIMP‐1 in breast cancer cells and that this interaction contributes to cellular internalization of TIMP‐1 and mediates intracellular signaling through the Akt signaling axis in breast cancer cells. These data provide new insights into the complex nature of the functions of TIMP‐1 and their potential mechanistic basis.
Plant physiology, Dec 21, 2016
While the importance of cell-type specificity in plant adaptive responses is widely accepted, onl... more While the importance of cell-type specificity in plant adaptive responses is widely accepted, only a limited number of studies have addressed this issue at the functional level. We have combined electrophysiological, imaging, and biochemical techniques to reveal physiological mechanisms conferring higher sensitivity of apical root cells to salinity in barley. We show that salinity application to the root apex arrests root growth in a highly tissue- and treatment-specific manner. Although salinity-induced transient net Na+ uptake was about 4-fold higher in the root apex compared with the mature zone, mature root cells accumulated more cytosolic and vacuolar Na+ suggesting that higher sensitivity of apical cells to salt is not related to either enhanced Na+ exclusion or sequestration inside the root. Rather, the above differential sensitivity between the two zones originates from a 10-fold difference in K+ efflux between the mature zone and the apical region (much poorer in the root a...
Communications Biology
Plasma membrane (PM) H+-ATPases are the electrogenic proton pumps that export H+ from plant and f... more Plasma membrane (PM) H+-ATPases are the electrogenic proton pumps that export H+ from plant and fungal cells to acidify the surroundings and generate a membrane potential. Plant PM H+-ATPases are equipped with a C‑terminal autoinhibitory regulatory (R) domain of about 100 amino acid residues, which could not be identified in the PM H+-ATPases of green algae but appeared fully developed in immediate streptophyte algal predecessors of land plants. To explore the physiological significance of this domain, we created in vivo C-terminal truncations of autoinhibited PM H+‑ATPase2 (AHA2), one of the two major isoforms in the land plant Arabidopsis thaliana. As more residues were deleted, the mutant plants became progressively more efficient in proton extrusion, concomitant with increased expansion growth and nutrient uptake. However, as the hyperactivated AHA2 also contributed to stomatal pore opening, which provides an exit pathway for water and an entrance pathway for pests, the mutant p...
<p>Curcumin (Sigma-Aldrich) was initially identified as a hit in an <i>in vitro</i... more <p>Curcumin (Sigma-Aldrich) was initially identified as a hit in an <i>in vitro</i> screen for inhibitors of the plasma membrane H<sup>+</sup>-ATPase. Curcumin (CM, <b>1</b>) demethoxycurcumin (DMCM, <b>2</b>), bisdemethoxycurcumin (BDCM, <b>3</b>) and 1,5-dihydroxy-1,7-bis(4-hydroxy-3-methoxyphenyl)-4,6-heptadien-3-one (<b>6</b>) were then purified as previous described [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163260#pone.0163260.ref039" target="_blank">39</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163260#pone.0163260.ref062" target="_blank">62</a>]. 6-shogaol (<b>4</b>) and dibenzylideneacetone (<b>9</b>) were obtained from Sigma-Aldrich. Tetrahydrocurcumin (<b>5</b>), 1,7-bis(3',4'-dimethoxyphenyl)-4,4-dimethyl-1,6-heptadien-3,5-dione (<b>7</b>) and 1-(3',4'-dimethoxyphenyl)-4,4-dimethyl-7-(4'-methoxyphenyl)-1,6-heptadien-3,5-dione (<b>8</b>) were synthesized as previously described in the literature[<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163260#pone.0163260.ref063" target="_blank">63</a>].</p
Perspectives for using genetically encoded fluorescent
Plant Physiology, 2021
Plant plasma membrane H+-ATPases and Ca2+-ATPases maintain low cytoplasmic concentrations of H+ a... more Plant plasma membrane H+-ATPases and Ca2+-ATPases maintain low cytoplasmic concentrations of H+ and Ca2+, respectively, and are essential for plant growth and development. These low concentrations allow plasma membrane H+-ATPases to function as electrogenic voltage stats, and Ca2+-ATPases as “off” mechanisms in Ca2+-based signal transduction. Although these pumps are autoregulated by cytoplasmic concentrations of H+ and Ca2+, respectively, they are also subject to exquisite regulation in response to biotic and abiotic events in the environment. A common paradigm for both types of pumps is the presence of terminal regulatory (R) domains that function as autoinhibitors that can be neutralized by multiple means, including phosphorylation. A picture is emerging in which some of the phosphosites in these R domains appear to be highly, nearly constantly phosphorylated, whereas others seem to be subject to dynamic phosphorylation. Thus, some sites might function as major switches, whereas ...
ChemMedChem, Jan 15, 2017
The fungal plasma membrane H+ -ATPase (Pma1p) is a potential target for the discovery of new anti... more The fungal plasma membrane H+ -ATPase (Pma1p) is a potential target for the discovery of new antifungal agents. Surprisingly, no structure-activity relationship studies for small molecules targeting Pma1p have been reported. Herein, we disclose a LEGO-inspired fragment assembly strategy for the design, synthesis, and discovery of benzo[d]thiazoles containing a 3,4-dihydroxyphenyl moiety as potential Pma1p inhibitors. A series of 2-(benzo[d]thiazol-2-ylthio)-1-(3,4-dihydroxyphenyl)ethanones was found to inhibit Pma1p, with the most potent IC50 value of 8 μm in an in vitro plasma membrane H+ -ATPase assay. These compounds were also found to strongly inhibit the action of proton pumping when Pma1p was reconstituted into liposomes. 1-(3,4-Dihydroxyphenyl)-2-((6-(trifluoromethyl)benzo[d]thiazol-2-yl)thio)ethan-1-one (compound 38) showed inhibitory activities on the growth of Candida albicans and Saccharomyces cerevisiae, which could be correlated and substantiated with the ability to inh...
Biophysical Journal, 2014
We have used time-resolved fluorescenceresonance energy transfer (TR-FRET) to study the structura... more We have used time-resolved fluorescenceresonance energy transfer (TR-FRET) to study the structural basis of regulation of sarcoplasmic reticulum Ca 2þ ATPase (SERCA) by a single-pass transmembrane protein, phospholamban (PLB). SERCA actively sequesters Ca 2þ back into the sarcoplasmic reticulum to cause muscle relaxation. In the heart, SERCA is inhibited by unphosphorylated PLB. Physiologically, this inhibition is relieved by either micromolar Ca 2þ or phosphorylation of PLB. Dysregulation of SERCA-PLB complex causes Ca 2þ mishandling in cardiomyocyte, which is a prominent feature in heart failure. Our goal is to elucidate the structural basis for the regulation of the complex, with an emphasis on the structural rearrangement during relief of inhibition. We have used time-resolved fluorescence resonance energy transfer (TR-FRET) to probe the complex directly by measuring the distances between SERCA (C674) and a series of positions on PLB in co-reconstituted vesicles. Our data supports that the cytoplasmic domain of bound PLB exists in two states. The relief of inhibition is achieved by combined effect of dissociation of the complex and shifting the equilibrium of the two states of bound PLB. Spectroscopy was performed in the Biophysical Spectroscopy Center at the University of Minnesota. This work was funded by NIH grants to DDT (R01 GM27906 and P30 AR0507220).
Plant Signaling & Behavior, 2011