Protein-protein interactions drive biological processes. They are critical for all intra- and extracellular functions, and the technologies to analyze them are widely applied throughout the various fields of biological sciences. This study takes an in-depth view of some common principles…
Unanchoring integrins in focal adhesions by Johanna Ivaska et al.
Focal adhesions are large structures through which integrins and scaffold proteins link the actin cytoskeleton to the extracellular matrix. A detailed analysis of integrin dynamics now indicates that focal-adhesion-associated integrins constantly switch between active and immobilized, and unbound and free-diffusing…
The R-Ras/RIN2/Rab5 complex controls endothelial cell adhesion and morphogenesis via active integrin endocytosis and Rac signaling by Chiara Sandri et al.
During developmental and tumor angiogenesis, semaphorins regulate blood vessel navigation by signaling through plexin receptors that inhibit the R-Ras subfamily of small GTPases. R-Ras is mainly expressed in vascular cells, where it induces adhesion to the extracellular matrix (ECM) through…
Negative regulators of integrin activity by Jeroen Pouwels et al.
Integrins are heterodimeric transmembrane adhesion receptors composed of α- and β-subunits. They are ubiquitously expressed and have key roles in a number of important biological processes, such as development, maintenance of tissue homeostasis and immunological responses. The activity of integrins,…
Distinct roles of AKT isoforms in regulating β1-integrin activity, migration, and invasion in prostate cancer by Reetta Virtakoivu et al.
AKT1 and AKT2 kinases have been shown to play opposite roles in breast cancer migration and invasion. In this study, an RNA interference screen for integrin activity inhibitors identified AKT1 as an inhibitor of β1-integrin activity in prostate cancer. Validation…
A functional genetic screen reveals new regulators of β1-integrin activity by Teijo Pellinen et al.
β1 integrins constitute a large group of widely distributed adhesion receptors, which regulate the ability of cells to interact with their surroundings. This regulation of the expression and activity of integrins is crucial for tissue homeostasis and development and contributes…
Distinct recycling of active and inactive β1 integrins by Antti Arjonen et al.
Integrin trafficking plays an important role in cellular motility and cytokinesis. Integrins undergo constant endo/exocytic shuttling to facilitate the dynamic regulation of cell adhesion. Integrin activity toward the components of the extracellular matrix is regulated by the ability of these…
Calpains promote α2β1 integrin turnover in nonrecycling integrin pathway by Nina Rintanen et al.
Collagen receptor integrins recycle between the plasma membrane and endosomes and facilitate formation and turnover of focal adhesions. In contrast, clustering of α2β1 integrin with antibodies or the human pathogen echovirus 1 (EV1) causes redistribution of α2 integrin to perinuclear…
Filopodia and adhesion in cancer cell motility by Antti Arjonen et al.
Slender bundled actin containing plasma membrane protrusions, called filopodia, are important for many essential cellular processes like cell adhesion, migration, angiogenesis and the formation of cell-cell contacts. In migrating cells, filopodia are the pioneers at the leading edge which probe…