Heart failure is a major clinical problem, with treatments involving medication, devices, and emerging neuromodulation therapies such as vagus nerve stimulation (VNS). Considering the ongoing interest in using VNS to treat cardiovascular disease, it is important to understand the genetic and molecular changes developing in the heart in response to this form of autonomic neuromodulation. This experimental animal (rat) study investigated the immediate transcriptional response of the ventricular myocardium to selective stimulation of vagal efferent activity using an optogenetic approach.
View Article and Find Full Text PDFCell Mol Biol Lett
July 2023
Background: Focal adhesions (FAs) are integrin-containing, multi-protein structures that link intracellular actin to the extracellular matrix and trigger multiple signaling pathways that control cell proliferation, differentiation, survival and motility. Microtubules (MTs) are stabilized in the vicinity of FAs through interaction with the components of the cortical microtubule stabilizing complex (CMSC). KANK (KN motif and ankyrin repeat domains) family proteins within the CMSC, KANK1 or KANK2, bind talin within FAs and thus mediate actin-MT crosstalk.
View Article and Find Full Text PDFPancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis due to its aggressive progression, late detection and lack of druggable driver mutations, which often combine to result in unsuitability for surgical intervention. Together with activating mutations of the small GTPase KRas, which are found in over 90% of PDAC tumours, a contributory factor for PDAC tumour progression is formation of a rigid extracellular matrix (ECM) and associated desmoplasia. This response leads to aberrant integrin signalling, and accelerated proliferation and invasion.
View Article and Find Full Text PDFIntegrins are heterodimeric cell surface glycoproteins used by cells to bind to the extracellular matrix (ECM) and regulate tumor cell proliferation, migration and survival. A causative relationship between integrin expression and resistance to anticancer drugs has been demonstrated in different tumors, including head and neck squamous cell carcinoma. Using a Cal27 tongue squamous cell carcinoma model, we have previously demonstrated that expression of integrin αVβ3 confers resistance to several anticancer drugs (cisplatin, mitomycin C and doxorubicin) through a mechanism involving downregulation of active Src, increased cell migration and invasion.
View Article and Find Full Text PDFExperimental in vitro models that capture pathophysiological characteristics of human tumours are essential for basic and translational cancer biology. Here, we describe a fully synthetic hydrogel extracellular matrix designed to elicit key phenotypic traits of the pancreatic environment in culture. To enable the growth of normal and cancerous pancreatic organoids from genetically engineered murine models and human patients, essential adhesive cues were empirically defined and replicated in the hydrogel scaffold, revealing a functional role of laminin-integrin α/α signalling in establishment and survival of pancreatic organoids.
View Article and Find Full Text PDFOncogene
August 2021
Intercellular mechanisms by which the stromal microenvironment contributes to solid tumor progression and targeted therapy resistance remain poorly understood, presenting significant clinical hurdles. PEAK1 (Pseudopodium-Enriched Atypical Kinase One) is an actin cytoskeleton- and focal adhesion-associated pseudokinase that promotes cell state plasticity and cancer metastasis by mediating growth factor-integrin signaling crosstalk. Here, we determined that stromal PEAK1 expression predicts poor outcomes in HER2-positive breast cancers high in SNAI2 expression and enriched for MSC content.
View Article and Find Full Text PDFTalin (TLN1) is a mechanosensitive component of adhesion complexes that directly couples integrins to the actin cytoskeleton. In response to force, talin undergoes switch-like behavior of its multiple rod domains that modulate interactions with its binding partners. Cyclin-dependent kinase-1 (CDK1) is a key regulator of the cell cycle, exerting its effects through synchronized phosphorylation of a large number of protein targets.
View Article and Find Full Text PDFInsulin signalling contributes to diverse cellular activities including protein synthesis, proliferation and cell survival. Insulin resistance describes the inability of cells to activate the insulin signalling pathway effectively; leading to pathological effects in multiple organ systems including the kidney. In diabetic kidney disease, there is progressive glomerular dysfunction and recent studies have demonstrated that the kidney podocyte is a direct target for insulin action.
View Article and Find Full Text PDFThe Kank (kidney or KN motif and ankyrin repeat domain-containing) family of proteins has been described as essential for crosstalk between actin and microtubules. Kank1, 2, 3 and 4 arose by gene duplication and diversification and share conserved structural domains. KANK proteins are localised mainly to the plasma membrane in focal adhesions, indirectly affecting RhoA and Rac1 thus regulating actin cytoskeleton.
View Article and Find Full Text PDFIntegrin adhesion complexes (IACs) bridge the extracellular matrix to the actin cytoskeleton and transduce signals in response to both chemical and mechanical cues. The composition, interactions, stoichiometry, and topological organization of proteins within IACs are not fully understood. To address this gap, we used multiplexed proximity biotinylation (BioID) to generate an in situ, proximity-dependent adhesome in mouse pancreatic fibroblasts.
View Article and Find Full Text PDFIntegrins are heterodimeric glycoproteins that bind cells to extracellular matrix. Upon integrin clustering, multimolecular integrin adhesion complexes (IACs) are formed, creating links to the cell cytoskeleton. We have previously observed decreased cell migration and increased sensitivity to microtubule (MT) poisons, paclitaxel and vincristine, in the melanoma cell line MDA-MB-435S upon transfection with integrin αV-specific siRNA, suggesting a link between adhesion and drug sensitivity.
View Article and Find Full Text PDFAn understanding of the mechanisms whereby cell adhesion complexes (ACs) relay signals bidirectionally across the plasma membrane is necessary to interpret the role of adhesion in regulating migration, differentiation, and growth. A range of AC types has been defined, but to date all have similar compositions and are dependent on a connection to the actin cytoskeleton. Recently, a new class of AC has been reported that normally lacks association with both the cytoskeleton and integrin-associated adhesome components, but is rich in components of the clathrin-mediated endocytosis machinery.
View Article and Find Full Text PDFIntegrin adhesion complexes (IACs) have evolved over millions of years to integrate metazoan cells physically with their microenvironment. It is presumed that the simultaneous interaction of thousands of integrin receptors to binding sites in anisotropic extracellular matrix (ECM) networks enables cells to assemble a topological description of the chemical and mechanical properties of their surroundings. This information is then converted into intracellular signals that influence cell positioning, differentiation and growth, but may also influence other fundamental processes, such as protein synthesis and energy regulation.
View Article and Find Full Text PDFIn most tissues, anchorage-dependent growth and cell cycle progression are dependent on cells engaging extracellular matrices (ECMs) via integrin-receptor adhesion complexes. In a highly conserved manner, cells disassemble adhesion complexes, round up, and retract from their surroundings before division, suggestive of a primordial link between the cell cycle machinery and the regulation of cell adhesion to the ECM. In this study, we demonstrate that cyclin-dependent kinase 1 (CDK1) mediates this link.
View Article and Find Full Text PDFIntegrin adhesion receptors engage with their extracellular matrix (ECM) ligands, initiating intracellular signaling pathways that regulate a range of fundamental cell functions. Protein kinases and phosphatases play an integral role in integrin adhesion-mediated signaling. However, until recently, knowledge of the phosphorylation sites regulated downstream of integrin ligation was limited to candidate-based approaches and did not support a system-level understanding of the molecular mechanisms through which ECM engagement influences cell behavior.
View Article and Find Full Text PDFThe adhesion nexus is the site at which integrin receptors bridge intracellular cytoskeletal and extracellular matrix networks. The connection between integrins and the cytoskeleton is mediated by a dynamic integrin adhesion complex (IAC), the components of which transduce chemical and mechanical signals to control a multitude of cellular functions. In this Cell Science at a Glance article and the accompanying poster, we integrate the consensus adhesome, a set of 60 proteins that have been most commonly identified in isolated IAC proteomes, with the literature-curated adhesome, a theoretical network that has been assembled through scholarly analysis of proteins that localise to IACs.
View Article and Find Full Text PDFIntegrin adhesion complexes (IACs) form mechanochemical connections between the extracellular matrix and actin cytoskeleton and mediate phenotypic responses via posttranslational modifications. Here, we investigate the modularity and robustness of the IAC network to pharmacological perturbation of the key IAC signaling components focal adhesion kinase (FAK) and Src. FAK inhibition using AZ13256675 blocked FAK(Y397) phosphorylation but did not alter IAC composition, as reported by mass spectrometry.
View Article and Find Full Text PDFCell and tissue stiffness have been known to contribute to both developmental and pathological signalling for some time, but the underlying mechanisms remain elusive. Integrins and their associated adhesion signalling complexes (IACs), which form a nexus between the cell cytoskeleton and the extracellular matrix, act as a key force sensing and transducing unit in cells. Accordingly, there has been much interest in obtaining a systems-level understanding of IAC composition.
View Article and Find Full Text PDFIntegrin receptor activation initiates the formation of integrin adhesion complexes (IACs) at the cell membrane that transduce adhesion-dependent signals to control a multitude of cellular functions. Proteomic analyses of isolated IACs have revealed an unanticipated molecular complexity; however, a global view of the consensus composition and dynamics of IACs is lacking. Here, we have integrated several IAC proteomes and generated a 2,412-protein integrin adhesome.
View Article and Find Full Text PDFPurpose: Multipotent mesenchymal stem cells (MSCs) have the capability to differentiate down adipocyte, osteocyte and chondrocyte lineages and as such offer a range of potential therapeutic applications. The composition and stiffness of the extracellular matrix (ECM) environment that surrounds cells dictates their transcriptional programme, thereby affecting stem cell lineage decision-making. Cells sense force via linkages between themselves and their microenvironment, and this is transmitted by integrin receptors and associated adhesion signalling complexes.
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