Understanding the relative orientation of protein secondary structure elements is crucial for elucidating their tertiary organization, function, and interactions. Here, we introduce HelixSide, a comprehensive method for systematically quantifying geometrical metrics of helical secondary structures, including widely used measures, such as tilt and kink angles. Additionally, to characterize the orientation of secondary structure motifs relative…

Constitutive integrin endocytosis and recycling control cell movement and morphology. In contrast, the role of newly synthesized integrins delivered via the biosynthetic pathway has been largely overlooked. We used the retention using selective hooks system to monitor the localization of new integrins exiting the endoplasmic reticulum in space and time. We discovered that new integrin…

Contractile actomyosin bundles, stress fibers, are important for cell migration, adhesion, morphogenesis, and mechanosensing. Calponin (CNN) family proteins are abundant stress fiber components, but their cellular functions and isoform-specific roles remain poorly understood. By depleting the three CNN isoforms (calponin-1 [CNN1], calponin-2 [CNN2], and calponin-3 [CNN3]) individually and collectively from U2OS cells, we show that…

Formation of the skin barrier is essential for organismal survival and tissue homeostasis. Barrier formation requires positioning of functional tight junctions (TJs) to the most suprabasal viable layer of the epidermis through a mechanical circuit that is driven by generation of high tension at adherens junctions. However, what allows the sensing of tension build-up at…

Mitochondria have a crucial role in regulating cellular homeostasis in response to intrinsic and extrinsic cues by changing cellular metabolism to meet these challenges. However, the molecular underpinnings of this regulation and the complete spectrum of these physiological outcomes remain largely unexplored. In this study, we elucidate the mechanisms driving the whitening phenotype in brown…

Integrin β1-mediated adhesion is dispensable in early mouse embryogenesis (pre-implantation) but indispensable post-implantation, suggesting distinct roles for β1-integrin-mediated adhesions in the naive (pre-implantation) versus primed (post-implantation) pluripotent stem cells (PSCs). We investigated the role of integrin β1 in regulating naive-like and primed human induced PSC (hiPSC) states. We find that integrin β1 is active in…

Epithelial protein lost in neoplasm (EPLIN), an actin-binding protein, has been described as both a tumor promoter and tumor suppressor in different cancers. The roles of EPLIN isoforms (α/β) remain largely unknown and could explain these opposing views. We observed distinct EPLIN isoform localization in breast cancer cells; EPLINα is recruited to actin in plasma…

Lymphatic capillaries continuously take up interstitial fluid and adapt to resulting changes in vessel calibre1-3. The mechanisms by which the permeable monolayer of loosely connected lymphatic endothelial cells (LECs)4 maintains mechanical stability remain elusive. Here we identify dynamic cytoskeletal regulation of LEC shape, induced by isotropic stretch, as crucial for the integrity and function of…

Integrins provide an essential bridge between cancer cells and the extracellular matrix, playing a central role in every stage of disease progression. Despite the recognized importance of integrin phosphorylation in several biological processes, the regulatory mechanisms and their relevance remained elusive. Here we engineer a fluorescence resonance energy transfer biosensor for integrin β1 phosphorylation, screening…