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  1. Article ; Online: Correlative light and electron microscopy reveals fork-shaped structures at actin entry sites of focal adhesions.

    Legerstee, Karin / Sueters, Jason / Abraham, Tsion E / Slotman, Johan A / Kremers, Gert-Jan / Hoogenboom, Jacob P / Houtsmuller, Adriaan B

    Biology open

    2022  Volume 11, Issue 11

    Abstract: Focal adhesions (FAs) are the main cellular structures to link the intracellular cytoskeleton to the extracellular matrix. FAs mediate cell adhesion, are important for cell migration and are involved in many (patho)-physiological processes. Here we ... ...

    Abstract Focal adhesions (FAs) are the main cellular structures to link the intracellular cytoskeleton to the extracellular matrix. FAs mediate cell adhesion, are important for cell migration and are involved in many (patho)-physiological processes. Here we examined FAs and their associated actin fibres using correlative fluorescence and scanning electron microscopy (SEM). We used fluorescence images of cells expressing paxillin-GFP to define the boundaries of FA complexes in SEM images, without using SEM contrast enhancing stains. We observed that SEM contrast was increased around the actin fibre entry site in 98% of FAs, indicating increases in protein density and possibly also phosphorylation levels in this area. In nearly three quarters of the FAs, these nanostructures had a fork shape, with the actin forming the stem and the high-contrast FA areas the fork. In conclusion, the combination of fluorescent and electron microscopy allowed accurate localisation of a highly abundant, novel fork structure at the FA-actin interface.
    MeSH term(s) Focal Adhesions/metabolism ; Actins/metabolism ; Cytoskeleton/metabolism ; Cell Adhesion ; Microscopy, Electron
    Chemical Substances Actins
    Language English
    Publishing date 2022-11-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 2632264-X
    ISSN 2046-6390 ; 2046-6390
    ISSN (online) 2046-6390
    ISSN 2046-6390
    DOI 10.1242/bio.059417
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Growth factor dependent changes in nanoscale architecture of focal adhesions.

    Legerstee, Karin / Abraham, Tsion E / van Cappellen, Wiggert A / Nigg, Alex L / Slotman, Johan A / Houtsmuller, Adriaan B

    Scientific reports

    2021  Volume 11, Issue 1, Page(s) 2315

    Abstract: Focal adhesions (FAs) are flat elongated structures that mediate cell migration and link the cytoskeleton to the extracellular matrix. Along the vertical axis FAs were shown to be composed of three layers. We used structured illumination microscopy to ... ...

    Abstract Focal adhesions (FAs) are flat elongated structures that mediate cell migration and link the cytoskeleton to the extracellular matrix. Along the vertical axis FAs were shown to be composed of three layers. We used structured illumination microscopy to examine the longitudinal distribution of four hallmark FA proteins, which we also used as markers for these layers. At the FA ends pointing towards the adherent membrane edge (heads), bottom layer protein paxillin protruded, while at the opposite ends (tails) intermediate layer protein vinculin and top layer proteins zyxin and VASP extended further. At the tail tips, only intermediate layer protein vinculin protruded. Importantly, head and tail compositions were altered during HGF-induced scattering with paxillin heads being shorter and zyxin tails longer. Additionally, FAs at protruding or retracting membrane edges had longer paxillin heads than FAs at static edges. These data suggest that redistribution of FA-proteins with respect to each other along FAs is involved in cell movement.
    MeSH term(s) Animals ; Cell Movement/immunology ; Cell Movement/physiology ; Cytoskeleton/genetics ; Cytoskeleton/metabolism ; Focal Adhesions/genetics ; Focal Adhesions/physiology ; Immunity, Cellular/genetics ; Immunity, Cellular/physiology ; Paxillin/genetics ; Paxillin/metabolism ; Vinculin/genetics ; Vinculin/metabolism ; Zyxin/genetics ; Zyxin/metabolism
    Chemical Substances Paxillin ; Zyxin ; Vinculin (125361-02-6)
    Language English
    Publishing date 2021-01-27
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-021-81898-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: DNA binding alters ARv7 dimer interactions.

    Özgün, Fatma / Kaya, Zeynep / Morova, Tunç / Geverts, Bart / Abraham, Tsion E / Houtsmuller, Adriaan B / van Royen, Martin E / Lack, Nathan A

    Journal of cell science

    2021  Volume 134, Issue 14

    Abstract: Androgen receptor (AR) splice variants are proposed to be a potential driver of lethal castration-resistant prostate cancer. AR splice variant 7 (ARv7) is the most commonly observed isoform and strongly correlates with resistance to second-generation ... ...

    Abstract Androgen receptor (AR) splice variants are proposed to be a potential driver of lethal castration-resistant prostate cancer. AR splice variant 7 (ARv7) is the most commonly observed isoform and strongly correlates with resistance to second-generation anti-androgens. Despite this clinical evidence, the interplay between ARv7 and the highly expressed full-length AR (ARfl) remains unclear. In this work, we show that ARfl/ARv7 heterodimers readily form in the nucleus via an intermolecular N/C interaction that brings the four termini of the proteins in close proximity. Combining fluorescence resonance energy transfer and fluorescence recovery after photobleaching, we demonstrate that these heterodimers undergo conformational changes following DNA binding, indicating dynamic nuclear receptor interaction. Although transcriptionally active, ARv7 can only form short-term interactions with DNA at highly accessible high-occupancy ARfl binding sites. Dimerization with ARfl does not affect ARv7 binding dynamics, suggesting that DNA binding occupancy is determined by the individual protein monomers and not the homodimer or heterodimer complex. Overall, these biophysical studies reveal detailed properties of ARv7 dynamics as both a homodimer or heterodimer with ARfl.
    MeSH term(s) Cell Line, Tumor ; Humans ; Male ; Prostatic Neoplasms, Castration-Resistant ; Protein Isoforms ; Receptors, Androgen/genetics
    Chemical Substances Protein Isoforms ; Receptors, Androgen
    Language English
    Publishing date 2021-07-28
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2993-2
    ISSN 1477-9137 ; 0021-9533
    ISSN (online) 1477-9137
    ISSN 0021-9533
    DOI 10.1242/jcs.258332
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Compartmentalization of androgen receptors at endogenous genes in living cells.

    Yavuz, Selçuk / Kabbech, Hélène / van Staalduinen, Jente / Linder, Simon / van Cappellen, Wiggert A / Nigg, Alex L / Abraham, Tsion E / Slotman, Johan A / Quevedo, Marti / Poot, Raymond A / Zwart, Wilbert / van Royen, Martin E / Grosveld, Frank G / Smal, Ihor / Houtsmuller, Adriaan B

    Nucleic acids research

    2023  Volume 51, Issue 20, Page(s) 10992–11009

    Abstract: A wide range of nuclear proteins are involved in the spatio-temporal organization of the genome through diverse biological processes such as gene transcription and DNA replication. Upon stimulation by testosterone and translocation to the nucleus, ... ...

    Abstract A wide range of nuclear proteins are involved in the spatio-temporal organization of the genome through diverse biological processes such as gene transcription and DNA replication. Upon stimulation by testosterone and translocation to the nucleus, multiple androgen receptors (ARs) accumulate in microscopically discernable foci which are irregularly distributed in the nucleus. Here, we investigated the formation and physical nature of these foci, by combining novel fluorescent labeling techniques to visualize a defined chromatin locus of AR-regulated genes-PTPRN2 or BANP-simultaneously with either AR foci or individual AR molecules. Quantitative colocalization analysis showed evidence of AR foci formation induced by R1881 at both PTPRN2 and BANP loci. Furthermore, single-particle tracking (SPT) revealed three distinct subdiffusive fractional Brownian motion (fBm) states: immobilized ARs were observed near the labeled genes likely as a consequence of DNA-binding, while the intermediate confined state showed a similar spatial behavior but with larger displacements, suggesting compartmentalization by liquid-liquid phase separation (LLPS), while freely mobile ARs were diffusing in the nuclear environment. All together, we show for the first time in living cells the presence of AR-regulated genes in AR foci.
    MeSH term(s) Animals ; Cell Nucleus/genetics ; Cell Nucleus/metabolism ; Nuclear Proteins/metabolism ; Receptors, Androgen/metabolism ; Humans ; Mice ; Cell Line, Tumor
    Chemical Substances Nuclear Proteins ; Receptors, Androgen
    Language English
    Publishing date 2023-10-04
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 186809-3
    ISSN 1362-4962 ; 1362-4954 ; 0301-5610 ; 0305-1048
    ISSN (online) 1362-4962 ; 1362-4954
    ISSN 0301-5610 ; 0305-1048
    DOI 10.1093/nar/gkad803
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Comparison of High- and Low-LET Radiation-Induced DNA Double-Strand Break Processing in Living Cells.

    Roobol, Stefan J / van den Bent, Irene / van Cappellen, Wiggert A / Abraham, Tsion E / Paul, Maarten W / Kanaar, Roland / Houtsmuller, Adriaan B / van Gent, Dik C / Essers, Jeroen

    International journal of molecular sciences

    2020  Volume 21, Issue 18

    Abstract: High-linear-energy-transfer (LET) radiation is more lethal than similar doses of low-LET radiation types, probably a result of the condensed energy deposition pattern of high-LET radiation. Here, we compare high-LET α-particle to low-LET X-ray ... ...

    Abstract High-linear-energy-transfer (LET) radiation is more lethal than similar doses of low-LET radiation types, probably a result of the condensed energy deposition pattern of high-LET radiation. Here, we compare high-LET α-particle to low-LET X-ray irradiation and monitor double-strand break (DSB) processing. Live-cell microscopy was used to monitor DNA double-strand breaks (DSBs), marked by p53-binding protein 1 (53BP1). In addition, the accumulation of the endogenous 53BP1 and replication protein A (RPA) DSB processing proteins was analyzed by immunofluorescence. In contrast to α-particle-induced 53BP1 foci, X-ray-induced foci were resolved quickly and more dynamically as they showed an increase in 53BP1 protein accumulation and size. In addition, the number of individual 53BP1 and RPA foci was higher after X-ray irradiation, while focus intensity was higher after α-particle irradiation. Interestingly, 53BP1 foci induced by α-particles contained multiple RPA foci, suggesting multiple individual resection events, which was not observed after X-ray irradiation. We conclude that high-LET α-particles cause closely interspaced DSBs leading to high local concentrations of repair proteins. Our results point toward a change in DNA damage processing toward DNA end-resection and homologous recombination, possibly due to the depletion of soluble protein in the nucleoplasm. The combination of closely interspaced DSBs and perturbed DNA damage processing could be an explanation for the increased relative biological effectiveness (RBE) of high-LET α-particles compared to X-ray irradiation.
    MeSH term(s) Alpha Particles ; Cell Line, Tumor ; DNA Breaks, Double-Stranded ; DNA Repair/radiation effects ; Humans ; X-Rays
    Language English
    Publishing date 2020-09-09
    Publishing country Switzerland
    Document type Comparative Study ; Journal Article
    ZDB-ID 2019364-6
    ISSN 1422-0067 ; 1422-0067 ; 1661-6596
    ISSN (online) 1422-0067
    ISSN 1422-0067 ; 1661-6596
    DOI 10.3390/ijms21186602
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Halogen-substituted anthranilic acid derivatives provide a novel chemical platform for androgen receptor antagonists.

    Roell, Daniela / Rösler, Thomas W / Hessenkemper, Wiebke / Kraft, Florian / Hauschild, Monique / Bartsch, Sophie / Abraham, Tsion E / Houtsmuller, Adriaan B / Matusch, Rudolf / van Royen, Martin E / Baniahmad, Aria

    The Journal of steroid biochemistry and molecular biology

    2019  Volume 188, Page(s) 59–70

    Abstract: Androgen receptor (AR) antagonists are used for hormone therapy of prostate cancer (PCa). However resistance to the treatment occurs eventually. One possible reason is the occurrence of AR mutations that prevent inhibition of AR-mediated transactivation ... ...

    Abstract Androgen receptor (AR) antagonists are used for hormone therapy of prostate cancer (PCa). However resistance to the treatment occurs eventually. One possible reason is the occurrence of AR mutations that prevent inhibition of AR-mediated transactivation by antagonists. To offer in future more options to inhibit AR signaling, novel chemical lead structures for new AR antagonists would be beneficial. Here we analyzed structure-activity relationships of a battery of 36 non-steroidal structural variants of methyl anthranilate including 23 synthesized compounds. We identified structural requirements that lead to more potent AR antagonists. Specific compounds inhibit the transactivation of wild-type AR as well as AR mutants that render treatment resistance to hydroxyflutamide, bicalutamide and the second-generation AR antagonist enzalutamide. This suggests a distinct mode of inhibiting the AR compared to the clinically used compounds. Competition assays suggest binding of these compounds to the AR ligand binding domain and inhibit PCa cell proliferation. Moreover, active compounds induce cellular senescence despite inhibition of AR-mediated transactivation indicating a transactivation-independent AR-pathway. In line with this, fluorescence resonance after photobleaching (FRAP) - assays reveal higher mobility of the AR in the cell nuclei. Mechanistically, fluorescence resonance energy transfer (FRET) - assays indicate that the amino-carboxy (N/C)-interaction of the AR is not affected, which is in contrast to known AR-antagonists. This suggests a mechanistically novel mode of AR-antagonism. Together, these findings indicate the identification of a novel chemical platform as a new lead structure that extends the diversity of known AR antagonists and possesses a distinct mode of antagonizing AR-function.
    MeSH term(s) Androgen Receptor Antagonists/chemistry ; Androgen Receptor Antagonists/pharmacology ; Animals ; COS Cells ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Chlorocebus aethiops ; Halogenation ; Humans ; Male ; Mutation ; Pancreatic Neoplasms/drug therapy ; Pancreatic Neoplasms/genetics ; Pancreatic Neoplasms/metabolism ; Receptors, Androgen/genetics ; Receptors, Androgen/metabolism ; ortho-Aminobenzoates/chemistry ; ortho-Aminobenzoates/pharmacology
    Chemical Substances Androgen Receptor Antagonists ; Receptors, Androgen ; ortho-Aminobenzoates ; anthranilic acid (0YS975XI6W)
    Language English
    Publishing date 2019-01-04
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1049188-0
    ISSN 1879-1220 ; 0960-0760
    ISSN (online) 1879-1220
    ISSN 0960-0760
    DOI 10.1016/j.jsbmb.2018.12.005
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Uptake and subcellular distribution of radiolabeled polymersomes for radiotherapy.

    Roobol, Stefan J / Hartjes, Thomas A / Slotman, Johan A / de Kruijff, Robin M / Torrelo, Guzman / Abraham, Tsion E / Bruchertseifer, Frank / Morgenstern, Alfred / Kanaar, Roland / van Gent, Dik C / Houtsmuller, Adriaan B / Denkova, Antonia G / van Royen, Martin E / Essers, Jeroen

    Nanotheranostics

    2020  Volume 4, Issue 1, Page(s) 14–25

    Abstract: Polymersomes have the potential to be applied in targeted alpha radionuclide therapy, while in addition preventing release of recoiling daughter isotopes. In this study, we investigated the cellular uptake, post uptake processing and intracellular ... ...

    Abstract Polymersomes have the potential to be applied in targeted alpha radionuclide therapy, while in addition preventing release of recoiling daughter isotopes. In this study, we investigated the cellular uptake, post uptake processing and intracellular localization of polymersomes.
    MeSH term(s) Animals ; Bismuth/chemistry ; Bismuth/pharmacokinetics ; Cell Line ; Cell Line, Tumor ; Drug Carriers/chemistry ; Drug Carriers/pharmacokinetics ; Endocytosis ; Humans ; Membranes, Artificial ; Mice ; Microscopy, Confocal ; Nanoparticles/chemistry ; Nanoparticles/metabolism ; Organic Chemicals/chemistry ; Organic Chemicals/pharmacokinetics ; Polymers/chemistry ; Polymers/pharmacokinetics ; Radioisotopes/chemistry ; Radioisotopes/pharmacokinetics ; Radiotherapy
    Chemical Substances Drug Carriers ; Membranes, Artificial ; Organic Chemicals ; PKH67 ; Polymers ; Radioisotopes ; Bismuth (U015TT5I8H)
    Language English
    Publishing date 2020-01-01
    Publishing country Australia
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2206-7418
    ISSN (online) 2206-7418
    DOI 10.7150/ntno.37080
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Staphylococcal

    Hoppenbrouwers, Tamara / Sultan, Andi R / Abraham, Tsion E / Lemmens-den Toom, Nicole A / Hansenová Maňásková, Silvie / van Cappellen, Wiggert A / Houtsmuller, Adriaan B / van Wamel, Willem J B / de Maat, Moniek P M / van Neck, Johan W

    Frontiers in immunology

    2018  Volume 9, Page(s) 165

    Abstract: Staphylococcus ... ...

    Abstract Staphylococcus aureus
    MeSH term(s) Adult ; Cells, Cultured ; Culture Media/chemistry ; Extracellular Traps/immunology ; Extracellular Traps/microbiology ; Humans ; Microbial Viability ; Middle Aged ; Neutrophil Activation ; Neutrophils/immunology ; Staphylococcal Infections/immunology ; Staphylococcal Protein A/immunology ; Staphylococcus aureus/metabolism
    Chemical Substances Culture Media ; Staphylococcal Protein A
    Language English
    Publishing date 2018-02-05
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2606827-8
    ISSN 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2018.00165
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  9. Article ; Online: In vitro induction of NETosis: Comprehensive live imaging comparison and systematic review.

    Hoppenbrouwers, Tamara / Autar, Anouchska S A / Sultan, Andi R / Abraham, Tsion E / van Cappellen, Wiggert A / Houtsmuller, Adriaan B / van Wamel, Willem J B / van Beusekom, Heleen M M / van Neck, Johan W / de Maat, Moniek P M

    PloS one

    2017  Volume 12, Issue 5, Page(s) e0176472

    Abstract: Background: Multiple inducers of in vitro Neutrophil Extracellular Trap (NET) formation (NETosis) have been described. Since there is much variation in study design and results, our aim was to create a systematic review of NETosis inducers and perform a ...

    Abstract Background: Multiple inducers of in vitro Neutrophil Extracellular Trap (NET) formation (NETosis) have been described. Since there is much variation in study design and results, our aim was to create a systematic review of NETosis inducers and perform a standardized in vitro study of NETosis inducers important in (cardiac) wound healing.
    Methods: In vitro NETosis was studied by incubating neutrophils with PMA, living and dead bacteria (S. aureus and E. coli), LPS, (activated) platelets (supernatant), glucose and calcium ionophore Ionomycin using 3-hour periods of time-lapse confocal imaging.
    Results: PMA is a consistent and potent inducer of NETosis. Ionomycin also consistently resulted in extrusion of DNA, albeit with a process that differs from the NETosis process induced by PMA. In our standardized experiments, living bacteria were also potent inducers of NETosis, but dead bacteria, LPS, (activated) platelets (supernatant) and glucose did not induce NETosis.
    Conclusion: Our systematic review confirms that there is much variation in study design and results of NETosis induction. Our experimental results confirm that under standardized conditions, PMA, living bacteria and Ionomycin all strongly induce NETosis, but real-time confocal imaging reveal different courses of events.
    MeSH term(s) Escherichia coli/physiology ; Extracellular Traps ; Fluorescent Antibody Technique ; Humans ; In Vitro Techniques ; Myocardium/pathology ; Staphylococcus aureus/physiology ; Wound Healing
    Language English
    Publishing date 2017
    Publishing country United States
    Document type Journal Article ; Review
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0176472
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Staphylococcal protein a is a key factor in neutrophil extracellular traps formation

    Hoppenbrouwers, Tamara / Sultan, Andi R. / Abraham, Tsion E. / Lemmens-den Toom, Nicole A. / Manásková, Silvie Hansenová / van Cappellen, Wiggert A. / Houtsmuller, Adriaan B. / van Wamel, Willem J.B. / de Maat, Moniek P.M. / van Neck, Johan W.

    Frontiers in Immunology

    2018  Volume 9

    Abstract: Staphylococcus aureus are strong inducers of neutrophil extracellular traps (NETs), a defense mechanism of neutrophils against pathogens. Our aim was to explore the role of Protein A in S. aureus-induced NETosis. We determined the Protein A production of ...

    Abstract Staphylococcus aureus are strong inducers of neutrophil extracellular traps (NETs), a defense mechanism of neutrophils against pathogens. Our aim was to explore the role of Protein A in S. aureus-induced NETosis. We determined the Protein A production of four different S. aureus strains and found a direct relationship between the degree of NETosis induction and Protein A production: strains producing higher concentrations of Protein A evoke significantly more NETs. A S. aureus strain in which Protein A as well as a second binding protein for immunoglobulins (Sbi) have been knocked-out (ΔSpA ΔSbi) induced significantly less NETosis than the wild-type strain. NETosis induction by this knockout strain can be rescued by the addition of purified Protein A. Dead S. aureus did not induce NETosis. In conclusion, Protein A is a determinant for NETosis induction by S. aureus.
    Keywords NETs ; Neutrophil extracellular traps ; Protein A ; S. aureus ; SpA ; Staphylococcus aureus
    Language English
    Publishing country nl
    Document type Article ; Online
    ZDB-ID 2606827-8
    ISSN 1664-3224
    ISSN 1664-3224
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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