scholarly journals So far, yet so close: α-Catenin dimers help migrating cells get together

2017 ◽  
Vol 216 (11) ◽  
pp. 3437-3439
Author(s):  
Laura Machesky ◽  
Vania M.M. Braga
Keyword(s):  
Plasma Membrane ◽  
Epithelial Cells ◽  
Active Plasma ◽  
Cell Biol ◽  
Membrane Protrusions ◽  
Freely Moving ◽  
And Migration ◽  
Migrating Cells

Epithelial cells in tissues use their actin cytoskeletons to stick together, whereas unattached cells make active plasma membrane protrusions to migrate. In this issue, Wood et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201612006) show that the junction component α-catenin is critical in freely moving cells to promote adhesion and migration.

scholarly journals Membrane-proximal F-actin restricts local membrane protrusions and directs cell migration

Science ◽  
2020 ◽  
Vol 368 (6496) ◽  
pp. 1205-1210 ◽  
Author(s):  
Anjali Bisaria ◽  
Arnold Hayer ◽  
Damien Garbett ◽  
Daniel Cohen ◽  
Tobias Meyer
Keyword(s):  
Plasma Membrane ◽  
Cell Migration ◽  
Cell Polarization ◽  
Density Gradients ◽  
Membrane Protrusion ◽  
Fluorescent Reporter ◽  
Membrane Protrusions ◽  
Directed Polymerization ◽  
Actin Concentration ◽  
Migrating Cells

Cell migration is driven by local membrane protrusion through directed polymerization of F-actin at the front. However, F-actin next to the plasma membrane also tethers the membrane and thus resists outgoing protrusions. Here, we developed a fluorescent reporter to monitor changes in the density of membrane-proximal F-actin (MPA) during membrane protrusion and cell migration. Unlike the total F-actin concentration, which was high in the front of migrating cells, MPA density was low in the front and high in the back. Back-to-front MPA density gradients were controlled by higher cofilin-mediated turnover of F-actin in the front. Furthermore, nascent membrane protrusions selectively extended outward from areas where MPA density was reduced. Thus, locally low MPA density directs local membrane protrusions and stabilizes cell polarization during cell migration.

scholarly journals The Human AC133 Hematopoietic Stem Cell Antigen Is also Expressed in Epithelial Cells and Targeted to Plasma Membrane Protrusions

2000 ◽  
Vol 275 (8) ◽  
pp. 5512-5520 ◽  
Author(s):  
Denis Corbeil ◽  
Katja Röper ◽  
Andrea Hellwig ◽  
Manuela Tavian ◽  
Sheri Miraglia ◽  
...  
Keyword(s):  
Stem Cell ◽  
Plasma Membrane ◽  
Epithelial Cells ◽  
Hematopoietic Stem Cell ◽  
Hematopoietic Stem ◽  
Cell Antigen ◽  
Membrane Protrusions

scholarly journals Do migrating cells need a nucleus?

2018 ◽  
Vol 217 (3) ◽  
pp. 799-801 ◽  
Author(s):  
Rhoda J. Hawkins
Keyword(s):  
Cell Polarity ◽  
Three Dimensions ◽  
Mechanical Responses ◽  
Cell Biol ◽  
And Migration ◽  
Migrating Cells

How the nucleus affects cell polarity and migration is unclear. In this issue, Graham et al. (2018. J. Cell Biol. https://doi.org/10.1083/jcb.201706097) show that enucleated cells polarize and migrate in two but not three dimensions and propose that the nucleus is a necessary component of the molecular clutch regulating normal mechanical responses.

scholarly journals T-Plastin reinforces membrane protrusions to bridge matrix gaps during cell migration

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Damien Garbett ◽  
Anjali Bisaria ◽  
Changsong Yang ◽  
Dannielle G. McCarthy ◽  
Arnold Hayer ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Cell Migration ◽  
Actin Filaments ◽  
Myosin Ii ◽  
Adhesion Sites ◽  
Membrane Protrusions ◽  
And Migration ◽  
Muscle Myosin ◽  
Migrating Cells

Abstract Migrating cells move across diverse assemblies of extracellular matrix (ECM) that can be separated by micron-scale gaps. For membranes to protrude and reattach across a gap, actin filaments, which are relatively weak as single filaments, must polymerize outward from adhesion sites to push membranes towards distant sites of new adhesion. Here, using micropatterned ECMs, we identify T-Plastin, one of the most ancient actin bundling proteins, as an actin stabilizer that promotes membrane protrusions and enables bridging of ECM gaps. We show that T-Plastin widens and lengthens protrusions and is specifically enriched in active protrusions where F-actin is devoid of non-muscle myosin II activity. Together, our study uncovers critical roles of the actin bundler T-Plastin to promote protrusions and migration when adhesion is spatially-gapped.

scholarly journals MYADM regulates Rac1 targeting to ordered membranes required for cell spreading and migration

2011 ◽  
Vol 22 (8) ◽  
pp. 1252-1262 ◽  
Author(s):  
Juan F. Aranda ◽  
Natalia Reglero-Real ◽  
Leonor Kremer ◽  
Beatriz Marcos-Ramiro ◽  
Ana Ruiz-Sáenz ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Cell Migration ◽  
Mammalian Cells ◽  
Cell Spreading ◽  
Membrane Domains ◽  
Membrane Raft ◽  
General Process ◽  
Membrane Protrusions ◽  
Differentiation Marker ◽  
And Migration

Membrane organization into condensed domains or rafts provides molecular platforms for selective recruitment of proteins. Cell migration is a general process that requires spatiotemporal targeting of Rac1 to membrane rafts. The protein machinery responsible for making rafts competent to recruit Rac1 remains elusive. Some members of the MAL family of proteins are involved in specialized processes dependent on this type of membrane. Because condensed membrane domains are a general feature of the plasma membrane of all mammalian cells, we hypothesized that MAL family members with ubiquitous expression and plasma membrane distribution could be involved in the organization of membranes for cell migration. We show that myeloid-associated differentiation marker (MYADM), a protein with unique features within the MAL family, colocalizes with Rac1 in membrane protrusions at the cell surface and distributes in condensed membranes. MYADM knockdown (KD) cells had altered membrane condensation and showed deficient incorporation of Rac1 to membrane raft fractions and, similar to Rac1 KD cells, exhibited reduced cell spreading and migration. Results of rescue-of-function experiments by expression of MYADM or active Rac1L61 in cells knocked down for Rac1 or MYADM, respectively, are consistent with the idea that MYADM and Rac1 act on parallel pathways that lead to similar functional outcomes.

scholarly journals Bayonets over bombs: RIPK3 and MLKL restrict Listeria without triggering necroptosis

2019 ◽  
Vol 218 (6) ◽  
pp. 1773-1775 ◽  
Author(s):  
Ting Zhang ◽  
Siddharth Balachandran
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Epithelial Cells ◽  
Necrotic Cell Death ◽  
Necrotic Cell ◽  
Membrane Rupture ◽  
Cell Biol ◽  
Bacterial Replication

RIPK3 induces necroptosis by phosphorylating MLKL, which then induces plasma membrane rupture and necrotic cell death. In this issue, Sai et al. (2019. J. Cell Biol. https://doi.org/10.1083/jcb.201810014) show that RIPK3-MLKL signaling in epithelial cells promotes Listeria clearance by directly suppressing cytosolic bacterial replication, without activating cell death.

Selective localization of the polytopic membrane protein prominin in microvilli of epithelial cells - a combination of apical sorting and retention in plasma membrane protrusions

1999 ◽  
Vol 112 (7) ◽  
pp. 1023-1033 ◽  
Author(s):  
D. Corbeil ◽  
K. Roper ◽  
M.J. Hannah ◽  
A. Hellwig ◽  
W.B. Huttner
Keyword(s):  
Plasma Membrane ◽  
Epithelial Cells ◽  
Cell Surface ◽  
Mdck Cells ◽  
Apical Plasma Membrane ◽  
Membrane Domain ◽  
Membrane Protrusions ◽  
Selective Retention ◽  
Polytopic Membrane Protein ◽  
Plasma Membrane Domain

Prominin is a recently identified polytopic membrane protein expressed in various epithelial cells, where it is selectively associated with microvilli. When expressed in non-epithelial cells, prominin is enriched in plasma membrane protrusions. This raises the question of whether the selective association of prominin with microvilli in epithelial cells is solely due to its preference for, and stabilization in, plasma membrane protrusions, or is due to both sorting to the apical plasma membrane domain and subsequent enrichment in plasma membrane protrusions. To investigate this question, we have generated stably transfected MDCK cells expressing either full-length or C-terminally truncated forms of mouse prominin. Confocal immunofluorescence and domain-selective cell surface biotinylation experiments on transfected MDCK cells grown on permeable supports demonstrated the virtually exclusive apical localization of prominin at steady state. Pulse-chase experiments in combination with domain-selective cell surface biotinylation showed that newly synthesized prominin was directly targeted to the apical plasma membrane domain. Immunoelectron microscopy revealed that prominin was confined to microvilli rather than the planar region of the apical plasma membrane. Truncation of the cytoplasmic C-terminal tail of prominin impaired neither its apical cell surface expression nor its selective retention in microvilli. Both the apical-specific localization of prominin and its selective retention in microvilli were maintained when MDCK cells were cultured in low-calcium medium, i.e. in the absence of tight junctions. Taken together, our results show that: (i) prominin contains dual targeting information, for direct delivery to the apical plasma membrane domain and for the enrichment in the microvillar subdomain; and (ii) this dual targeting does not require the cytoplasmic C-terminal tail of prominin and still occurs in the absence of tight junctions. The latter observation suggests that entry into, and retention in, plasma membrane protrusions may play an important role in the establishment and maintenance of the apical-basal polarity of epithelial cells.

scholarly journals Regulation of desmosome assembly in MDCK epithelial cells: coordination of membrane core and cytoplasmic plaque domain assembly at the plasma membrane.

1991 ◽  
Vol 113 (3) ◽  
pp. 645-655 ◽  
Author(s):  
M Pasdar ◽  
K A Krzeminski ◽  
W J Nelson
Keyword(s):  
Plasma Membrane ◽  
Epithelial Cells ◽  
Sucrose Gradient ◽  
Integral Membrane Proteins ◽  
Junctional Complex ◽  
Immunofluorescence Analysis ◽  
Cell Biol ◽  
Cytoskeletal Elements ◽  
Triton X

Desmosomes are major components of the intercellular junctional complex in epithelia. They consist of at least eight different cytoplasmic and integral membrane proteins that are organized into two biochemically and structurally distinct domains: the cytoplasmic plaque and membrane core. We showed previously that in MDCK epithelial cells major components of the cytoplasmic plaque (desmoplakin I and II; DPI/II) and membrane core domains (desmoglein I; DGI) initially enter a pool of proteins that is soluble in buffers containing Triton X-100, and then titrate into an insoluble pool before their arrival at the plasma membrane (Pasdar, M., and W. J. Nelson. 1988. J. Cell Biol. 106:677-685; Pasdar. M., and W. J. Nelson. 1989. J. Cell Biol. 109:163-177). We have now examined whether either the soluble or insoluble pool of these proteins represents an intracellular site for assembly and interactions between the domains before their assembly into desmosomes at the plasma membrane. Interactions between the Triton X-100-soluble pools of DPI/II and DGI were analyzed by sedimentation of extracted proteins in sucrose gradients. Results show distinct differences in the sedimentation profiles of these proteins, suggesting that they are not associated in the Triton X-100-soluble pool of proteins; this was also supported by the observation that DGI and DPI/II could not be coimmunoprecipitated in a complex with each other from sucrose gradient fractions. Immunofluorescence analysis of the insoluble pools of DPI/II and DGI, in cells in which desmosome assembly had been synchronized, showed distinct differences in the spatial distributions of these proteins. Furthermore, DPI/II and DGI were found to be associated with different elements of cytoskeleton; DPI/II were located along cytokeratin intermediate filaments, whereas DGI appeared to be associated with microtubules. The regulatory role of cytoskeletal elements in the intracellular organization and assembly of the cytoplasmic plaque and membrane core domains, and their integration into desmosomes on the plasma membrane is discussed.

Membrane microdomains: lessons from microscopy

1995 ◽  
Vol 53 ◽  
pp. 776-777
Author(s):  
J.M. Robinson ◽  
J.M Oliver
Keyword(s):  
Spatial Distribution ◽  
Plasma Membrane ◽  
Epithelial Cells ◽  
Plasma Membranes ◽  
Cell Types ◽  
Imaging Modalities ◽  
Membrane Microdomains ◽  
Membrane Domains ◽  
Lateral Heterogeneity ◽  
Functional Importance

Specialized regions of plasma membranes displaying lateral heterogeneity are the focus of this Symposium. Specialized membrane domains are known for certain cell types such as differentiated epithelial cells where lateral heterogeneity in lipids and proteins exists between the apical and basolateral portions of the plasma membrane. Lateral heterogeneity and the presence of microdomains in membranes that are uniform in appearance have been more difficult to establish. Nonetheless a number of studies have provided evidence for membrane microdomains and indicated a functional importance for these structures.This symposium will focus on the use of various imaging modalities and related approaches to define membrane microdomains in a number of cell types. The importance of existing as well as emerging imaging technologies for use in the elucidation of membrane microdomains will be highlighted. The organization of membrane microdomains in terms of dimensions and spatial distribution is of considerable interest and will be addressed in this Symposium.

Sign in / Sign up

Export Citation Format

Share Document