How does integrin clustering affect integrin signaling? Localization of Integrin The concentration of β subunits is generally high while that of α subunit is the factor limiting the amount of heterodimers that localize on the membrane [1]. Liganded integrins diffuse along the membrane and [...]

What is the role of the cytoskeleton in the regulation of cell-cell adhesions? Given the function and stability of clustered cell-cell adhesions is tightly coupled to the formation and function of the actin cytoskeleton, it is not surprising that many of the components that [...]

What are cell-matrix adhesions? The extracellular matrix and the basal lamina Cell-matrix adhesion is the interaction of a cell with the extracellular matrix, mediated by multi-protein adhesion structures such as focal adhesions, fibrillar adhesions and podosomes. The ECM is a network of extracellular molecules [...]

How do neurotrophins, collapsin, and ephrins, serve as guidance cues? Neurotrophins Stimulating filopodia formation A secreted guidance cue which stimulates filopodia formation in growth cones. Two examples of secreted neurotrophins, brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), mediate retinal ganglion cell axon [...]

What is the NF-κB pathway? NF-κB (nuclear factor kappa light chain enhancer of activated B cells) is a family of highly conserved transcription factors that regulate many important cellular behaviours, in particular, inflammatory responses, cellular growth and apoptosis [1][2]. NF-κB is also involved in [...]

What is the Hippo-YAP/TAZ tumor-suppressor pathway? Mechanical cues control Hippo-YAP/TAZ tumor-suppressor pathway The Hippo signaling pathway is a complex network of proteins that controls organ size via regulation of cellular proliferation, survival and differentiation. Initially discovered by genetic mosaic screens in Drosophila, the core [...]

What is the Canonical Wnt Receptor Signaling Pathway? The canonical Wnt receptor signaling pathway is a series of molecular events that are initiated by the binding of Wnt proteins to the frizzled family of receptors on the cell surface. This ultimately activates transcription factors [...]

How is SRF signaling activated? Myocardin, MAL (or MRTF-A) and MRTF-B are the best-studied examples of MRTFs. In the cytoplasm, MRTFs exist in a stable complex with monomeric G-actin via RPEL domains, which exist at their N terminal [1]. These domains also include the [...]

How is integrin activated? Integrin activation is an important mechanism through which cells regulate integrin function by manipulating the ligand affinity of integrins spatially and temporally. Structural and functional studies suggest that integrins can exist in different ligand affinity states – low, intermediate and [...]

What ligands bind to integrin? Integrin-Ligand specificity Humans have at least 18 α subtypes and 8 β subtypes which together generate 24 known binding pairs for the integrins heterodimer (reviewed in [1][2]). The α subunit of the integrin heterodimer especially the αI domain determines [...]

What is integrin extension? Integrin extension Upon alteration in the transmembrane and their proximal domains, the bent headpiece extends in less than 1 second [1] with intermediate affinity for ligands. Two models- “switchblade” and “deadbolt”- have been proposed for the mechanism of transmission of [...]

What are guidance cues? During neural development, highly motile structures on the developing neurites, called growth cones, are guided by signals from the extracellular environment. Guidance cues come in many different forms, from diffusible extracellular proteins and lipid factors, to extracellular matrix proteins and/or [...]