Adaptation of cell shape and polarization through the formation and retraction of cellular protrusions requires balancing of endocytosis and exocytosis combined with fine-tuning of the local activity of small GTPases like Rab8. Here, we show that endocytic turnover of the plasma membrane at protrusions is directly coupled to surface removal and inactivation of Rab8. Removal is induced by reduce...

The post-synaptic spines of neuronal dendrites are highly elaborate membrane protrusions. Their anatomy, stability and density are intimately linked to cognitive performance. The morphological transitions of spines are powered by coordinated polymerization of actin filaments against the plasma membrane, but how the membrane-associated polymerization is spatially and temporally regulated has rem...

Low pulling forces applied locally to cell surface membranes produce viscoelastic cell surface protrusions. As the force increases, the membrane can locally separate from the cytoskeleton and a tether forms. Tethers can grow to great lengths exceeding the cell diameter. The protrusion-to-tether transition is known as the crossover. Here we propose a unified approach to protrusions and tethers p...

Abstract Cells migrate collectively to form tissues and organs during morphogenesis. Contact inhibition of locomotion (CIL) drives collective migration by inhibiting lamellipodial protrusions at cell–cell contacts promoting polarization the leading edge. Here, we report a CIL-related cell behavior myotubes that lack protrusions, but instead use filopodia move as cohesive cluster in formin-depen...

A facile and flexible synthesis for colloidal molecules with well-controlled shape and tunable patchiness is presented. Cross-linked polystyrene spheres with a liquid protrusion were found to assemble into colloidal molecules by coalescence of the liquid protrusions. Similarly, cross-linked poly(methyl methacrylate) particles carrying a wetting layer assembled into colloidal molecules by coales...

BACKGROUND As measured from videocapsule endoscopy images, the small intestinal mucosa of untreated celiac patients has significantly greater and more varied texture compared to normal patients. Three-dimensional modeling using shape-from-shading principles may further increase classification accuracy. METHODS A sequence of 200 consecutive videocapsule images acquired at a 2s(-1) frame rate a...

BACKGROUND In animal cells, GTPase signaling pathways are thought to generate cellular protrusions by modulating the activity of downstream actin-regulatory proteins. Although the molecular events linking activation of a GTPase to the formation of an actin-based process with a characteristic morphology are incompletely understood, Rac-GTP is thought to promote the activation of SCAR/WAVE, where...

OBJECTIVE To investigate possible protrusions through stent cells, and the factors affecting protrusions after carotid angioplasty and stenting (CAS). METHODS This ex-vivo clinical study was performed between July 2010 and August 2011 at the Department of Radiology, Ege University School of Medicine, Izmir, Turkey. After approval by the Institutional Board, 15 successive carotid plaques, whic...

Thus far, 14 homologues of mammalian Rac proteins have been identified in Dictyostelium. It is unclear whether each of these genes has a unique function or to what extent they play redundant roles in actin cytoskeletal organization. To investigate the specific function of RacB, we have conditionally expressed wild-type (WT-RacB), dominant negative (N17-RacB), and constitutively activated (V12-R...

Although directed migration of eukaryotic cells may have evolved to escape nutrient depletion, it has been adopted for an extensive range of physiological events during development and in the adult organism. The subversion of these movements results in disease, such as cancer. Mechanisms of propulsion and sensing are extremely diverse, but most eukaryotic cells move by extending actin-filled pr...