A new potent antibacterial protein, for which we propose the name royalisin, was found in royal jelly of honeybee Apis mellifera L. and purified to homogeneity first time by acid extraction, gel filtration, reverse-phase high pressure liquid chromatography. The primary structure royalisin determined consist 51 residues, with three intramolecular disulfide linkages, having a calculated molecular mass 5523 Da. Royalisin is an amphipathic C-terminal half molecule being rich charged amino acids;...

Cyclic stretch is an artificial model of mechanical force loading, which induces the reorientation vascular endothelial cells (ECs) and their stress fibers in a direction perpendicular to axis. Rho family GTPases are crucial for cyclic stretch-induced EC reorientation; however, mechanism underlying activation unknown. A screen short-hairpin RNAs targeting 63 Rho-guanine nucleotide exchange factors (Rho-GEFs) revealed that at least 11 Rho-GEFs (Abr, Alsin, ARHGEF10, Bcr, GEF-H1, LARG,...

Epithelia must be able to resist mechanical force preserve tissue integrity. While intercellular junctions are known important for the resistance of epithelia, roles tight (TJs) remain established. We previously demonstrated that epithelial cells devoid TJ membrane proteins claudins and JAM-A completely lack TJs exhibit focal breakages their apical junctions. Here, we demonstrate fracture when claudin/JAM-A–deficient undergo spontaneous cell stretching. The junction was accompanied by actin...

Mechanical force–induced cytoskeletal reorganization is essential for cell and tissue remodeling homeostasis; however, the underlying cellular mechanisms remain elusive. Solo (ARHGEF40) a RhoA-targeting guanine nucleotide exchange factor (GEF) involved in cyclical stretch–induced human endothelial reorientation convergent extension movement zebrafish gastrula. In this study, we show that binds to keratin-8/keratin-18 (K8/K18) intermediate filaments through multiple sites. overexpression...

Epithelial to mesenchymal transition (EMT) is a fundamental biological process that occurs during development and tumorigenesis. The Rho family of GTPases (Rho-family) well-characterized regulator actin cytoskeleton gives rise EMT-associated cell activities. Meanwhile, there are in total at least 66 different Rho-GTPase-activating proteins (Rho-GAPs), which, as an upstream regulator, inactivate specific members the Rho-family context-dependent manner. However, molecular roles individual...

Keratin intermediate filament (IF) proteins constitute the major cytoskeletal components in epithelial cells. Missense mutations keratin 5 (K5; also known as KRT5) or 14 (K14; KRT14), highly expressed basal epidermis, cause severe skin blistering disease epidermolysis bullosa simplex (EBS). EBS-associated disrupt networks and change keratinocyte mechanics; however, molecular mechanisms by which shape EBS pathology remain incompletely understood. Here, we demonstrate that, contrast to...

Abstract Claudin‐based tight junctions (TJs) are formed at the most apical part of cell–cell contacts in epithelial cells. Previous studies suggest that scaffolding proteins ZO‐1 and ZO‐2 (ZO proteins) determine location TJs by interacting with claudins, but this idea is not conclusive. To address role ZO binding to claudins TJs, a COOH‐terminal PDZ domain motif‐deleted claudin‐3 mutant, which lacks protein binding, was stably expressed claudin‐deficient MDCK The COOH‐terminus‐deleted...

Lamellipodium extension is crucial for cell migration and spreading. The rate of lamellipodium determined by the balance between actin polymerization retrograde flow. LIM kinase 1 (LIMK1) regulates dynamics phosphorylating inactivating cofilin, an actin-depolymerizing protein. We examined role LIMK1 in measuring rates polymerization, flow, using time-lapse imaging fluorescence recovery after photobleaching. In non-extending lamellipodia active Rac-expressing N1E-115 cells, expression...

Cell-substrate adhesions are essential for various physiological processes, including embryonic development and maintenance of organ functions. Hemidesmosomes (HDs) multiprotein complexes that attach epithelial cells to the basement membrane. Formation remodeling HDs dependent on surrounding mechanical environment; however, upstream signaling mechanisms not well understood. We recently reported Solo (also known as ARHGEF40), a guanine nucleotide exchange factor targeting RhoA, binds...

The identification of a thymus antigen on rabbit cells has made it possible to determine the number and proportion RTLA (rabbit lymphocyte antigen) bearing derived in various lymphoid tissues. In an earlier study, this been measured by complement mediated cell kill. report, bursa-equivalent was obtained means immunofluorescenf staining. is agreement with that found cytotoxicity. Age dependent changes organ content Ig are described.

Abstract Solo (ARHGEF40) is a RhoA‐targeting guanine nucleotide exchange factor that regulates tensional force‐induced cytoskeletal reorganization. binds to keratin 8/keratin 18 (K8/K18) filaments through multiple sites, but the roles of these interactions in localization and mechanotransduction‐regulating function remain unclear. Here, we constructed two mutants (L14R/L17R L49R/L52R) with leucine‐to‐arginine replacements N‐terminal conserved region (which termed domain) analyzed their...

Collective cell migration is crucial for tissue remodeling and cancer invasion. A RhoA-targeting guanine nucleotide exchange factor, Solo, localizes to the cell–cell contact sites in collectively migrating cells acts as a brake collective via promoting RhoA-ROCK pathway regulating keratin-8/keratin-18 networks.

Epithelial tubules, consisting of the epithelial cell sheet with a central lumen, are basic structure many organs. Mechanical forces play an important role in tubulogenesis; however, little is known about mechanisms controlling mechanical during tubule morphogenesis. Solo (also as ARHGEF40) RhoA-targeting guanine-nucleotide exchange factor that involved force-induced RhoA activation and stress fiber formation. binds to keratin-8/keratin-18 (K8/K18) filaments, this interaction plays crucial...

Abstract Epithelia must be able to resist mechanical force preserve tissue integrity. While intercellular junctions are known important for the resistance of epithelia, roles tight (TJs) remain established. We previously demonstrated that epithelial cells devoid TJ membrane proteins claudins and JAM-A completely lack TJs exhibit focal breakages their apical junctions. Here, we demonstrate undergo spontaneous fracture when claudin/JAM-A-deficient exposed stress. The junction was accompanied...

Analysis the role of Rho -GEFs