LIVIVO - Das Suchportal für Lebenswissenschaften

switch to English language
Erweiterte Suche

Suchergebnis

Treffer 1 - 8 von insgesamt 8

Suchoptionen

  1. Artikel ; Online: Foregut organ progenitors and their niche display distinct viscoelastic properties in vivo during early morphogenesis stages.

    Dzementsei, Aliaksandr / Barooji, Younes F / Ober, Elke A / Oddershede, Lene B

    Communications biology

    2022  Band 5, Heft 1, Seite(n) 402

    Abstract: Material properties of living matter play an important role for biological function and development. Yet, quantification of material properties of internal organs in vivo, without causing physiological damage, remains challenging. Here, we present a non- ... ...

    Abstract Material properties of living matter play an important role for biological function and development. Yet, quantification of material properties of internal organs in vivo, without causing physiological damage, remains challenging. Here, we present a non-invasive approach based on modified optical tweezers for quantifying sub-cellular material properties deep inside living zebrafish embryos. Material properties of cells within the foregut region are quantified as deep as 150 µm into the biological tissue through measurements of the positions of an inert tracer. This yields an exponent, α, which characterizes the scaling behavior of the positional power spectra and the complex shear moduli. The measurements demonstrate differential mechanical properties: at the time when the developing organs undergo substantial displacements during morphogenesis, gut progenitors are more elastic (α = 0.57 ± 0.07) than the neighboring yolk (α = 0.73 ± 0.08), liver (α = 0.66 ± 0.06) and two mesodermal (α = 0.68 ± 0.06, α = 0.64 ± 0.06) progenitor cell populations. The higher elasticity of gut progenitors correlates with an increased cellular concentration of microtubules. The results infer a role of material properties during morphogenesis and the approach paves the way for quantitative material investigations in vivo of embryos, explants, or organoids.
    Mesh-Begriff(e) Animals ; Elasticity ; Endoderm ; Liver ; Morphogenesis ; Zebrafish
    Sprache Englisch
    Erscheinungsdatum 2022-04-29
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2399-3642
    ISSN (online) 2399-3642
    DOI 10.1038/s42003-022-03349-1
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  2. Artikel ; Online: Reduction in E-cadherin expression fosters migration of Xenopus laevis primordial germ cells

    Baronsky, Thilo / Dzementsei, Aliaksandr / Oelkers, Marieelen / Melchert, Juliane / Pieler, Tomas / Janshoff, Andreas

    Integrative biology. 2016 Mar. 14, v. 8, no. 3 p.349-358

    2016  

    Abstract: The transition from passive to active migration of primordial germ cells in Xenopus embryos correlates with a reduction in overall adhesion to surrounding endodermal cells as well as with reduced E-cadherin expression. Single cell force spectroscopy, in ... ...

    Abstract The transition from passive to active migration of primordial germ cells in Xenopus embryos correlates with a reduction in overall adhesion to surrounding endodermal cells as well as with reduced E-cadherin expression. Single cell force spectroscopy, in which cells are brought into brief contact with a gold surface functionalized with E-cadherin constructs, allows for a quantitative estimate of functional E-cadherin molecules on the cell surface. The adhesion force between migratory PGCs and the cadherin-coated surface was almost identical to cells where E-cadherin was knocked down by morpholino oligonucleotides (180 pN). In contrast, non-migratory PGCs display significantly higher adhesion forces (270 pN) on E-cadherin functionalised surfaces. On the basis of these observations, we propose that migration of PGCs in Xenopus embryos is regulated via modulation of E-cadherin expression levels, allowing these cells to move more freely if the level of E-cadherin is reduced.
    Schlagwörter Xenopus laevis ; cadherins ; germ cells ; gold ; oligonucleotides ; spectroscopy
    Sprache Englisch
    Erscheinungsverlauf 2016-0314
    Umfang p. 349-358.
    Erscheinungsort The Royal Society of Chemistry
    Dokumenttyp Artikel ; Online
    ZDB-ID 2480063-6
    ISSN 1757-9708 ; 1757-9694
    ISSN (online) 1757-9708
    ISSN 1757-9694
    DOI 10.1039/c5ib00291e
    Datenquelle NAL Katalog (AGRICOLA)

    Zusatzmaterialien

    Kategorien

  3. Artikel: Migratory and adhesive properties of Xenopus laevis primordial germ cells in vitro.

    Dzementsei, Aliaksandr / Schneider, David / Janshoff, Andreas / Pieler, Tomas

    Biology open

    2013  Band 2, Heft 12, Seite(n) 1279–1287

    Abstract: The directional migration of primordial germ cells (PGCs) to the site of gonad formation is an advantageous model system to study cell motility. The embryonic development of PGCs has been investigated in different animal species, including mice, ... ...

    Abstract The directional migration of primordial germ cells (PGCs) to the site of gonad formation is an advantageous model system to study cell motility. The embryonic development of PGCs has been investigated in different animal species, including mice, zebrafish, Xenopus and Drosophila. In this study we focus on the physical properties of Xenopus laevis PGCs during their transition from the passive to the active migratory state. Pre-migratory PGCs from Xenopus laevis embryos at developmental stages 17-19 to be compared with migratory PGCs from stages 28-30 were isolated and characterized in respect to motility and adhesive properties. Using single-cell force spectroscopy, we observed a decline in adhesiveness of PGCs upon reaching the migratory state, as defined by decreased attachment to extracellular matrix components like fibronectin, and a reduced adhesion to somatic endodermal cells. Data obtained from qPCR analysis with isolated PGCs reveal that down-regulation of E-cadherin might contribute to this weakening of cell-cell adhesion. Interestingly, however, using an in vitro migration assay, we found that movement of X. laevis PGCs can also occur independently of specific interactions with their neighboring cells. The reduction of cellular adhesion during PGC development is accompanied by enhanced cellular motility, as reflected in increased formation of bleb-like protrusions and inferred from electric cell-substrate impedance sensing (ECIS) as well as time-lapse image analysis. Temporal alterations in cell shape, including contraction and expansion of the cellular body, reveal a higher degree of cellular dynamics for the migratory PGCs in vitro.
    Sprache Englisch
    Erscheinungsdatum 2013-12-15
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 2632264-X
    ISSN 2046-6390
    ISSN 2046-6390
    DOI 10.1242/bio.20135140
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  4. Artikel ; Online: Reduction in E-cadherin expression fosters migration of Xenopus laevis primordial germ cells.

    Baronsky, Thilo / Dzementsei, Aliaksandr / Oelkers, Marieelen / Melchert, Juliane / Pieler, Tomas / Janshoff, Andreas

    Integrative biology : quantitative biosciences from nano to macro

    2016  Band 8, Heft 3, Seite(n) 349–358

    Abstract: The transition from passive to active migration of primordial germ cells in Xenopus embryos correlates with a reduction in overall adhesion to surrounding endodermal cells as well as with reduced E-cadherin expression. Single cell force spectroscopy, in ... ...

    Abstract The transition from passive to active migration of primordial germ cells in Xenopus embryos correlates with a reduction in overall adhesion to surrounding endodermal cells as well as with reduced E-cadherin expression. Single cell force spectroscopy, in which cells are brought into brief contact with a gold surface functionalized with E-cadherin constructs, allows for a quantitative estimate of functional E-cadherin molecules on the cell surface. The adhesion force between migratory PGCs and the cadherin-coated surface was almost identical to cells where E-cadherin was knocked down by morpholino oligonucleotides (180 pN). In contrast, non-migratory PGCs display significantly higher adhesion forces (270 pN) on E-cadherin functionalised surfaces. On the basis of these observations, we propose that migration of PGCs in Xenopus embryos is regulated via modulation of E-cadherin expression levels, allowing these cells to move more freely if the level of E-cadherin is reduced.
    Mesh-Begriff(e) Animals ; Cadherins/antagonists & inhibitors ; Cadherins/genetics ; Cadherins/metabolism ; Cell Adhesion ; Cell Movement/genetics ; Cell Movement/physiology ; Embryonic Germ Cells/cytology ; Embryonic Germ Cells/metabolism ; Endoderm/metabolism ; Gene Expression Regulation, Developmental ; Gene Knockdown Techniques ; Single-Cell Analysis ; Xenopus Proteins/antagonists & inhibitors ; Xenopus Proteins/genetics ; Xenopus Proteins/metabolism ; Xenopus laevis/embryology ; Xenopus laevis/genetics ; Xenopus laevis/metabolism
    Chemische Substanzen Cadherins ; Xenopus Proteins
    Sprache Englisch
    Erscheinungsdatum 2016-03-14
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2480063-6
    ISSN 1757-9708 ; 1757-9694
    ISSN (online) 1757-9708
    ISSN 1757-9694
    DOI 10.1039/c5ib00291e
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  5. Artikel ; Online: A novel function for KIF13B in germ cell migration.

    Tarbashevich, Katsiaryna / Dzementsei, Aliaksandr / Pieler, Tomas

    Developmental biology

    2011  Band 349, Heft 2, Seite(n) 169–178

    Abstract: Primordial germ cell (PGC) development in Xenopus embryos relies on localised maternal determinants. We report on the identification and functional characterisation of such one novel activity, a germ plasm associated mRNA encoding for the Xenopus version ...

    Abstract Primordial germ cell (PGC) development in Xenopus embryos relies on localised maternal determinants. We report on the identification and functional characterisation of such one novel activity, a germ plasm associated mRNA encoding for the Xenopus version of a kinesin termed KIF13B. Modulations of xKIF13B function result in germ cell mismigration and in reduced numbers of such cells. PGCs explanted from Xenopus embryos form bleb-like protrusions enriched in PIP3. Knockdown of xKIF13B results in inhibition of blebbing and PIP3 accumulation. Interference with PIP3 synthesis leads to PGC mismigration in vivo and in vitro. We propose that xKIF13B function is linked to polarized accumulation of PIP3 and directional migration of the PGCs in Xenopus embryos.
    Mesh-Begriff(e) Animals ; Cell Movement/genetics ; Cell Movement/physiology ; Cell Polarity/physiology ; Cloning, Molecular ; Gene Knockdown Techniques ; Germ Cells/physiology ; In Situ Hybridization ; Kinesin/genetics ; Kinesin/metabolism ; Phosphatidylinositol 3-Kinases/metabolism ; RNA, Messenger/metabolism ; Xenopus laevis/embryology
    Chemische Substanzen RNA, Messenger ; Phosphatidylinositol 3-Kinases (EC 2.7.1.-) ; Kinesin (EC 3.6.4.4)
    Sprache Englisch
    Erscheinungsdatum 2011-01-15
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1114-9
    ISSN 1095-564X ; 0012-1606
    ISSN (online) 1095-564X
    ISSN 0012-1606
    DOI 10.1016/j.ydbio.2010.10.016
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  6. Buch ; Online ; Dissertation / Habilitation: Role of cellular dynamics, adhesion and polarity in the context of primordial germ cell migration in Xenopus laevis embryos

    Dzementsei, Aliaksandr / Dosch, Roland / Halyna, Shcherbata / Janshoff, Andreas / Kessel, Michael / Pieler, Thomas / Wodarz, Andreas

    2013  

    Abstract: Directional cell migration is an intensively studied process relevant for both normal development of an organism as well as for a number of pathological conditions such as chronic inflammation and cancer. Primordial germ cells (PGCs) in Xenopus laevis ... ...

    Verfasserangabe vorgelegt von Aliaksandr Dzementsei
    Abstract Directional cell migration is an intensively studied process relevant for both normal development of an organism as well as for a number of pathological conditions such as chronic inflammation and cancer. Primordial germ cells (PGCs) in Xenopus laevis embryos can be used as a model system to study cell migration, since during embryogenesis they actively migrate within the endoderm towards genital ridges. Transition to active cell migration is a highly regulated process important for the normal PGC development in many species. This study is focused on molecular and cellular mechanisms involv...
    Sprache Englisch
    Umfang Online-Ressource (PDF-Datei: 5,1 MB)
    Dokumenttyp Buch ; Online ; Dissertation / Habilitation
    Dissertation / Habilitation Univ., Diss.--Göttingen, 2013
    Datenquelle Ehemaliges Sondersammelgebiet Küsten- und Hochseefischerei

    Zusatzmaterialien

    Kategorien

  7. Artikel ; Online: EphrinB1/EphB3b Coordinate Bidirectional Epithelial-Mesenchymal Interactions Controlling Liver Morphogenesis and Laterality.

    Cayuso, Jordi / Dzementsei, Aliaksandr / Fischer, Johanna C / Karemore, Gopal / Caviglia, Sara / Bartholdson, Josefin / Wright, Gavin J / Ober, Elke A

    Developmental cell

    2016  Band 39, Heft 3, Seite(n) 316–328

    Abstract: Positioning organs in the body often requires the movement of multiple tissues, yet the molecular and cellular mechanisms coordinating such movements are largely unknown. Here, we show that bidirectional signaling between EphrinB1 and EphB3b coordinates ... ...

    Abstract Positioning organs in the body often requires the movement of multiple tissues, yet the molecular and cellular mechanisms coordinating such movements are largely unknown. Here, we show that bidirectional signaling between EphrinB1 and EphB3b coordinates the movements of the hepatic endoderm and adjacent lateral plate mesoderm (LPM), resulting in asymmetric positioning of the zebrafish liver. EphrinB1 in hepatoblasts regulates directional migration and mediates interactions with the LPM, where EphB3b controls polarity and movement of the LPM. EphB3b in the LPM concomitantly repels hepatoblasts to move leftward into the liver bud. Cellular protrusions controlled by Eph/Ephrin signaling mediate hepatoblast motility and long-distance cell-cell contacts with the LPM beyond immediate tissue interfaces. Mechanistically, intracellular EphrinB1 domains mediate EphB3b-independent hepatoblast extension formation, while EpB3b interactions cause their destabilization. We propose that bidirectional short- and long-distance cell interactions between epithelial and mesenchyme-like tissues coordinate liver bud formation and laterality via cell repulsion.
    Mesh-Begriff(e) Animals ; Body Patterning ; Cell Movement ; Cell Shape ; Ephrin-B1/metabolism ; Ephrin-B3/metabolism ; Epithelium/embryology ; Epithelium/metabolism ; Functional Laterality ; Liver/embryology ; Mesoderm/embryology ; Mesoderm/metabolism ; Morphogenesis ; Pseudopodia/metabolism ; Receptors, Eph Family/metabolism ; Zebrafish/embryology ; Zebrafish/metabolism ; Zebrafish Proteins/metabolism
    Chemische Substanzen EphB3b protein, zebrafish ; Ephrin-B1 ; Ephrin-B3 ; Zebrafish Proteins ; Receptors, Eph Family (EC 2.7.10.1)
    Sprache Englisch
    Erscheinungsdatum 2016-11-09
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2054967-2
    ISSN 1878-1551 ; 1534-5807
    ISSN (online) 1878-1551
    ISSN 1534-5807
    DOI 10.1016/j.devcel.2016.10.009
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  8. Artikel: novel function for KIF13B in germ cell migration

    Tarbashevich, Katsiaryna / Dzementsei, Aliaksandr / Pieler, Tomas

    Developmental biology

    Band v. 349,, Heft no. 2

    Abstract: Primordial germ cell (PGC) development in Xenopus embryos relies on localised maternal determinants. We report on the identification and functional characterisation of such one novel activity, a germ plasm associated mRNA encoding for the Xenopus version ...

    Abstract Primordial germ cell (PGC) development in Xenopus embryos relies on localised maternal determinants. We report on the identification and functional characterisation of such one novel activity, a germ plasm associated mRNA encoding for the Xenopus version of a kinesin termed KIF13B. Modulations of xKIF13B function result in germ cell mismigration and in reduced numbers of such cells. PGCs explanted from Xenopus embryos form bleb-like protrusions enriched in PIP3. Knockdown of xKIF13B results in inhibition of blebbing and PIP3 accumulation. Interference with PIP3 synthesis leads to PGC mismigration in vivo and in vitro. We propose that xKIF13B function is linked to polarized accumulation of PIP3 and directional migration of the PGCs in Xenopus embryos.
    Schlagwörter germ cells ; cell movement ; messenger RNA ; germplasm ; Xenopus ; kinesin
    Sprache Englisch
    Dokumenttyp Artikel
    ISSN 0012-1606
    Datenquelle AGRIS - International Information System for the Agricultural Sciences and Technology

    Zusatzmaterialien

    Kategorien

Zum Seitenanfang