Random versus directionally persistent cell migration

Abstract

Directional migration is an important component of cell motility. Although the basic mechanisms of random cell movement are well characterized, no single model explains the complex regulation of directional migration. Multiple factors operate at each step of cell migration to stabilize lamellipodia and maintain directional migration. Factors such as topography of the extracellular matrix, the cellular polarity machinery, receptor signalling, integrin trafficking and co-receptors, and actin–myosin contraction converge on regulation of the Rho family of GTPases and control of lamellipodial protrusions to promote directional migration.

Integrin signalling adaptors: not only figurants in the cancer story

“…These events induce cell migration through actin cytoskeleton remodelling, pseudopodia extension and focal adhesion turnover [51][52][53] . Uncoupling of p130CAS-CRK negatively regulates cell migration.…”

New insights regarding the regulation of chemotaxis by nucleotides, adenosine, and their receptors

“…Such pseudopod formation is biased (i.e., occurs at one end of the cell) even in the absence of an external signal. Cell polarization involves the detection of extracellular cues and progression through a series of cytoskeletal rearrangements that promote the protrusion of a leading edge of a cell and the release of integrin-based contacts with the substratum and contraction at the rear of the cell (i.e., the uropod; [11]). Cell polarization is central to the migration of many cell types.…”

“…Certain cell types exposed to a uniform concentration of chemoattractant do not polarize, but instead undergo chemokinesis (i.e., random cell migration; [11]). However, some types of cells (e.g., neutrophils and the slime mold Dictyostelium discoidium) can polarize under such conditions; such cell types can detect and amplify spatial gradients even while immobile, a process called gradient sensing [8].…”

Arpin, un nouvel inhibiteur du complexe Arp2/3, contrôle la migration cellulaire

“…Nous avons donc ensuite cherché à caractéri-ser dans quel site cellulaire Arpin exerce sa fonction inhibitrice. Actine branchée Rac pas partie de la machinerie motrice requise pour la migration, mais c'est un inhibiteur puissant de la migration cellulaire, qui diminue vitesse et direction, les deux paramètres majeurs qui déterminent l'efficacité de la migration [10]. Nous nous attendons à ce qu'Arpin soit impliquée dans de nombreux processus physiologiques dans lesquels intervient une régulation fine de la migration cellulaire.…”

“…Ces types de souvenirs peuvent être très détaillés et il a été démontré que dans un contexte émotionnellement saillant et lié à la survie de l'individu, on observait une augmentation de la reconstruction de souvenirs [10], ce qui pourrait être le cas dans les souvenirs d'EMI. ‡ Can the phenomenology of near death experiences memories be compared to memories of real and imagined events?…”