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1.
J Cell Biol ; 223(10)2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-38889096

RESUMEN

Immune cells are highly dynamic and able to migrate through environments with diverse biochemical and mechanical compositions. Their migration has classically been defined as amoeboid under the assumption that it is integrin independent. Here, we show that activated primary Th1 T cells require both confinement and extracellular matrix proteins to migrate efficiently. This migration is mediated through small and dynamic focal adhesions that are composed of the same proteins associated with canonical mesenchymal cell focal adhesions, such as integrins, talin, and vinculin. These focal adhesions, furthermore, localize to sites of contractile traction stresses, enabling T cells to pull themselves through confined spaces. Finally, we show that Th1 T cells preferentially follow tracks of other T cells, suggesting that these adhesions modify the extracellular matrix to provide additional environmental guidance cues. These results demonstrate not only that the boundaries between amoeboid and mesenchymal migration modes are ambiguous, but that integrin-mediated focal adhesions play a key role in T cell motility.


Asunto(s)
Movimiento Celular , Matriz Extracelular , Adhesiones Focales , Integrinas , Talina , Adhesiones Focales/metabolismo , Animales , Integrinas/metabolismo , Talina/metabolismo , Ratones , Matriz Extracelular/metabolismo , Vinculina/metabolismo , Ratones Endogámicos C57BL , Linfocitos T/inmunología , Linfocitos T/metabolismo , Activación de Linfocitos , Adhesión Celular
2.
Nat Commun ; 15(1): 4986, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862544

RESUMEN

Focal adhesions form liquid-like assemblies around activated integrin receptors at the plasma membrane. How they achieve their flexible properties is not well understood. Here, we use recombinant focal adhesion proteins to reconstitute the core structural machinery in vitro. We observe liquid-liquid phase separation of the core focal adhesion proteins talin and vinculin for a spectrum of conditions and interaction partners. Intriguingly, we show that binding to PI(4,5)P2-containing membranes triggers phase separation of these proteins on the membrane surface, which in turn induces the enrichment of integrin in the clusters. We suggest a mechanism by which 2-dimensional biomolecular condensates assemble on membranes from soluble proteins in the cytoplasm: lipid-binding triggers protein activation and thus, liquid-liquid phase separation of these membrane-bound proteins. This could explain how early focal adhesions maintain a structured and force-resistant organization into the cytoplasm, while still being highly dynamic and able to quickly assemble and disassemble.


Asunto(s)
Membrana Celular , Adhesiones Focales , Talina , Vinculina , Talina/metabolismo , Talina/química , Adhesiones Focales/metabolismo , Membrana Celular/metabolismo , Vinculina/metabolismo , Vinculina/química , Humanos , Animales , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfatidilinositol 4,5-Difosfato/química , Integrinas/metabolismo , Integrinas/química , Citoplasma/metabolismo , Unión Proteica , Separación de Fases
3.
Front Immunol ; 15: 1400819, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863696

RESUMEN

Background: Integrin-dependent cell adhesion and migration play important roles in systemic sclerosis (SSc). The roles of integrin activating molecules including talins and kindlins, however, are unclear in SSc. Objectives: We aimed to explore the function of integrin activating molecules in SSc. Methods: Transcriptome analysis of skin datasets of SSc patients was performed to explore the function of integrin-activating molecules including talin1, talin2, kindlin1, kindlin2 and kindlin3 in SSc. Expression of talin1 in skin tissue was assessed by multiplex immunohistochemistry staining. Levels of talin1 in serum were determined by ELISA. The effects of talin1 inhibition were analyzed in human dermal fibroblasts by real-time PCR, western blot and flow cytometry. Results: We identified that talin1 appeared to be the primary integrin activating molecule involved in skin fibrosis of SSc. Talin1 was significantly upregulated and positively correlates with the modified Rodnan skin thickness score (mRSS) and the expression of pro-fibrotic biomarkers in the skin lesions of SSc patients. Further analyses revealed that talin1 is predominantly expressed in the dermal fibroblasts of SSc skin and promotes fibroblast activation and collagen production. Additionally, talin1 primarily exerts its effects through integrin ß1 and ß5 in SSc. Conclusions: Overexpressed talin1 is participated in skin fibrosis of SSc, and talin1 appears to be a potential new therapeutic target for SSc.


Asunto(s)
Fibroblastos , Fibrosis , Esclerodermia Sistémica , Piel , Talina , Humanos , Esclerodermia Sistémica/metabolismo , Esclerodermia Sistémica/patología , Talina/metabolismo , Talina/genética , Piel/metabolismo , Piel/patología , Fibroblastos/metabolismo , Femenino , Masculino , Persona de Mediana Edad , Adulto , Células Cultivadas
4.
EMBO J ; 43(13): 2715-2732, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38769437

RESUMEN

Microtubules regulate cell polarity and migration via local activation of focal adhesion turnover, but the mechanism of this process is insufficiently understood. Molecular complexes containing KANK family proteins connect microtubules with talin, the major component of focal adhesions. Here, local optogenetic activation of KANK1-mediated microtubule/talin linkage promoted microtubule targeting to an individual focal adhesion and subsequent withdrawal, resulting in focal adhesion centripetal sliding and rapid disassembly. This sliding is preceded by a local increase of traction force due to accumulation of myosin-II and actin in the proximity of the focal adhesion. Knockdown of the Rho activator GEF-H1 prevented development of traction force and abolished sliding and disassembly of focal adhesions upon KANK1 activation. Other players participating in microtubule-driven, KANK-dependent focal adhesion disassembly include kinases ROCK, PAK, and FAK, as well as microtubules/focal adhesion-associated proteins kinesin-1, APC, and αTAT. Based on these data, we develop a mathematical model for a microtubule-driven focal adhesion disruption involving local GEF-H1/RhoA/ROCK-dependent activation of contractility, which is consistent with experimental data.


Asunto(s)
Adhesiones Focales , Cinesinas , Microtúbulos , Factores de Intercambio de Guanina Nucleótido Rho , Adhesiones Focales/metabolismo , Microtúbulos/metabolismo , Humanos , Factores de Intercambio de Guanina Nucleótido Rho/metabolismo , Factores de Intercambio de Guanina Nucleótido Rho/genética , Cinesinas/metabolismo , Cinesinas/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas del Citoesqueleto/metabolismo , Proteínas del Citoesqueleto/genética , Miosina Tipo II/metabolismo , Talina/metabolismo , Talina/genética , Animales
5.
Cell ; 187(12): 2990-3005.e17, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38772370

RESUMEN

Integrins link the extracellular environment to the actin cytoskeleton in cell migration and adhesiveness. Rapid coordination between events outside and inside the cell is essential. Single-molecule fluorescence dynamics show that ligand binding to the bent-closed integrin conformation, which predominates on cell surfaces, is followed within milliseconds by two concerted changes, leg extension and headpiece opening, to give the high-affinity integrin conformation. The extended-closed integrin conformation is not an intermediate but can be directly accessed from the extended-open conformation and provides a pathway for ligand dissociation. In contrast to ligand, talin, which links the integrin ß-subunit cytoplasmic domain to the actin cytoskeleton, modestly stabilizes but does not induce extension or opening. Integrin activation is thus initiated by outside-in signaling and followed by inside-out signaling. Our results further imply that talin binding is insufficient for inside-out integrin activation and that tensile force transmission through the ligand-integrin-talin-actin cytoskeleton complex is required.


Asunto(s)
Integrinas , Talina , Animales , Humanos , Ratones , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/química , Adhesión Celular , Células CHO , Cricetulus , Integrinas/metabolismo , Integrinas/química , Ligandos , Unión Proteica , Conformación Proteica , Transducción de Señal , Imagen Individual de Molécula , Talina/metabolismo , Talina/química
6.
J Cell Sci ; 137(9)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38587458

RESUMEN

Talin (herein referring collectively to talin 1 and 2) couples the actomyosin cytoskeleton to integrins and transmits tension to the extracellular matrix. Talin also interacts with numerous additional proteins capable of modulating the actin-integrin linkage and thus downstream mechanosignaling cascades. Here, we demonstrate that the scaffold protein Caskin2 interacts directly with the R8 domain of talin through its C-terminal LD motif. Caskin2 also associates with the WAVE regulatory complex to promote cell migration in an Abi1-dependent manner. Furthermore, we demonstrate that the Caskin2-Abi1 interaction is regulated by growth factor-induced phosphorylation of Caskin2 on serine 878. In MCF7 and UACC893 cells, which contain an amplification of CASKIN2, Caskin2 localizes in plasma membrane-associated plaques and around focal adhesions in cortical microtubule stabilization complexes. Taken together, our results identify Caskin2 as a novel talin-binding protein that might not only connect integrin-mediated adhesion to actin polymerization but could also play a role in crosstalk between integrins and microtubules.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Movimiento Celular , Proteínas del Citoesqueleto , Unión Proteica , Talina , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas del Citoesqueleto/metabolismo , Proteínas del Citoesqueleto/genética , Adhesiones Focales/metabolismo , Integrinas/metabolismo , Células MCF-7 , Microtúbulos/metabolismo , Fosforilación , Talina/metabolismo
7.
PLoS Genet ; 20(4): e1011224, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38662776

RESUMEN

Cell adhesion requires linkage of transmembrane receptors to the cytoskeleton through intermediary linker proteins. Integrin-based adhesion to the extracellular matrix (ECM) involves large adhesion complexes that contain multiple cytoskeletal adapters that connect to the actin cytoskeleton. Many of these adapters, including the essential cytoskeletal linker Talin, have been shown to contain multiple actin-binding sites (ABSs) within a single protein. To investigate the possible role of having such a variety of ways of linking integrins to the cytoskeleton, we generated mutations in multiple actin binding sites in Drosophila talin. Using this approach, we have been able to show that different actin-binding sites in talin have both unique and complementary roles in integrin-mediated adhesion. Specifically, mutations in either the C-terminal ABS3 or the centrally located ABS2 result in lethality showing that they have unique and non-redundant function in some contexts. On the other hand, flies simultaneously expressing both the ABS2 and ABS3 mutants exhibit a milder phenotype than either mutant by itself, suggesting overlap in function in other contexts. Detailed phenotypic analysis of ABS mutants elucidated the unique roles of the talin ABSs during embryonic development as well as provided support for the hypothesis that talin acts as a dimer in in vivo contexts. Overall, our work highlights how the ability of adhesion complexes to link to the cytoskeleton in multiple ways provides redundancy, and consequently robustness, but also allows a capacity for functional specialization.


Asunto(s)
Actinas , Adhesión Celular , Matriz Extracelular , Talina , Animales , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/genética , Actinas/metabolismo , Actinas/genética , Sitios de Unión , Adhesión Celular/genética , Citoesqueleto/metabolismo , Citoesqueleto/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Matriz Extracelular/metabolismo , Integrinas/metabolismo , Integrinas/genética , Mutación , Unión Proteica , Talina/metabolismo , Talina/genética
8.
Biomaterials ; 308: 122542, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38547833

RESUMEN

Focal adhesions (FAs) are nanoscale complexes containing clustered integrin receptors and intracellular structural and signaling proteins that function as principal sites of mechanotransduction in part via promoting the nuclear translocation and activation of the transcriptional coactivator yes-associated protein (YAP). Knockdown of FA proteins such as focal adhesion kinase (FAK), talin, and vinculin can prevent YAP nuclear localization. However, the mechanism(s) of action remain poorly understood. Herein, we investigated the role of different functional domains in vinculin, talin, and FAK in regulating YAP nuclear localization. Using genetic or pharmacological inhibition of fibroblasts and human mesenchymal stem cells (hMSCs) adhering to deformable substrates, we find that disruption of vinculin-talin binding versus talin-FAK binding reduces YAP nuclear localization and transcriptional activity via different mechanisms. Disruption of vinculin-talin binding or knockdown of talin-1 reduces nuclear size, traction forces, and YAP nuclear localization. In contrast, disruption of the talin binding site on FAK or elimination of FAK catalytic activity did not alter nuclear size yet still prevented YAP nuclear localization and activity. These data support both nuclear tension-dependent and independent models for matrix stiffness-regulated YAP nuclear localization. Our results highlight the importance of vinculin-talin-FAK interactions at FAs of adherent cells, controlling YAP nuclear localization and activity.


Asunto(s)
Núcleo Celular , Mecanotransducción Celular , Talina , Vinculina , Proteínas Señalizadoras YAP , Talina/metabolismo , Vinculina/metabolismo , Humanos , Núcleo Celular/metabolismo , Proteínas Señalizadoras YAP/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Factores de Transcripción/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Animales , Adhesiones Focales/metabolismo , Ratones , Fibroblastos/metabolismo , Quinasa 1 de Adhesión Focal/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Unión Proteica
9.
Proc Natl Acad Sci U S A ; 121(13): e2314947121, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38513099

RESUMEN

Protein kinase A (PKA) is a ubiquitous, promiscuous kinase whose activity is specified through subcellular localization mediated by A-kinase anchoring proteins (AKAPs). PKA has complex roles as both an effector and a regulator of integrin-mediated cell adhesion to extracellular matrix (ECM). Recent observations demonstrate that PKA is an active component of focal adhesions (FA), suggesting the existence of one or more FA AKAPs. Using a promiscuous biotin ligase fused to PKA type-IIα regulatory (RIIα) subunits and subcellular fractionation, we identify the archetypal FA protein talin1 as an AKAP. Talin is a large, mechanosensitive scaffold that directly links integrins to actin filaments and promotes FA assembly by recruiting additional components in a force-dependent manner. The rod region of talin1 consists of 62 α-helices bundled into 13 rod domains, R1 to R13. Direct binding assays and NMR spectroscopy identify helix41 in the R9 subdomain of talin as the PKA binding site. PKA binding to helix41 requires unfolding of the R9 domain, which requires the linker region between R9 and R10. Experiments with single molecules and in cells manipulated to alter actomyosin contractility demonstrate that the PKA-talin interaction is regulated by mechanical force across the talin molecule. Finally, talin mutations that disrupt PKA binding also decrease levels of total and phosphorylated PKA RII subunits as well as phosphorylation of VASP, a known PKA substrate, within FA. These observations identify a mechanically gated anchoring protein for PKA, a force-dependent binding partner for talin1, and a potential pathway for adhesion-associated mechanotransduction.


Asunto(s)
Proteínas de Anclaje a la Quinasa A , Adhesiones Focales , Adhesiones Focales/metabolismo , Proteínas de Anclaje a la Quinasa A/genética , Proteínas de Anclaje a la Quinasa A/metabolismo , Talina/metabolismo , Mecanotransducción Celular , Adhesión Celular/fisiología , Integrinas/metabolismo , Unión Proteica , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo
10.
Reprod Biomed Online ; 48(3): 103646, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38290387

RESUMEN

RESEARCH QUESTION: What is the relationship between ATG8 and integrin α4ß1, Talin-1, and Treg cell differentiation, and the effects on endometriosis (EMS)? DESIGN: First, the correlation between the ATG8, Talin-1, integrin α4ß1, and differentiation of Treg cells and EMS was examined in clinical samples. Human peripheral blood mononuclear cells (PBMC) and endometrial stromal cells were extracted and identified, oe-ATG8 and oe-integrin α4ß1 were transfected to overexpress ATG8 and integrin α4ß1, and Tregs cell differentiation and endometrial stromal cells (ESC) function were detected. In addition, the molecular mechanism by which ATG8 inhibited EMS disease progression at the molecular and animal levels was investigated. RESULTS: ATG8 expression was negatively correlated with positive proportion of Tregs cells (P = 0.0463). The expression of Talin-1 and integrin-α4ß1 (both P < 0.0001) in PBMC decreased significantly after oe-ATG8 transfection, whereas the Treg cells' positive rate significantly increased (P = 0.0003). The ESC proliferation, adhesion, migration, and invasion (all P < 0.0001) declined after co-culture with Treg cells that underwent oe-ATG8 transfection. The expression of Talin-1 (P = 0.0025) and integrin-α4ß1 (P = 0.0002) in PBMC increased significantly after oe-integrin α4ß1 and oe-ATG8 transfection. In addition, this transfection reversed the corresponding regulation of oe-ATG8 transfection. Finally, animal experiments in vivo confirmed that ATG8 inhibited EMS disease progression. CONCLUSION: The ATG8 regulated Treg cell differentiation and inhibited EMS formation by influencing the interaction between integrin α4ß1 and Talin-1.


Asunto(s)
Endometriosis , Integrina alfa4beta1 , Animales , Femenino , Humanos , Integrina alfa4beta1/metabolismo , Linfocitos T Reguladores , Talina/genética , Talina/metabolismo , Leucocitos Mononucleares/metabolismo , Diferenciación Celular , Progresión de la Enfermedad , Adhesión Celular
11.
J Exp Clin Cancer Res ; 43(1): 27, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38254102

RESUMEN

BACKGROUND: Peritoneal metastasis, which accounts for 85% of all epithelial ovarian carcinoma (EOC) metastases, is a multistep process that requires the establishment of adhesive interactions between cancer cells and the peritoneal membrane. Interrelations between EOC and the mesothelial stroma are critical to facilitate the metastatic process. No data is available so far on the impact of histone acetylation/deacetylation, a potentially relevant mechanism governing EOC metastasis, on mesothelial cells (MCs)-mediated adhesion. METHODS: Static adhesion and peritoneal clearance experiments were performed pretreating mesenchymal-like MCs and platinum-sensitive/resistant EOC cell lines with MS-275-a Histone deacetylase (HDAC)1-3 pharmacological inhibitor currently used in combination trials. Results were acquired by confocal microscopy and were analyzed with an automated Opera software. The role of HDAC1/2 was validated by genetic silencing. The role of α4-, α5-α1 Integrins and Fibronectin-1 was validated using specific monoclonal antibodies. Quantitative proteomic analysis was performed on primary MCs pretreated with MS-275. Decellularized matrices were generated from either MS-275-exposed or untreated cells to study Fibronectin-1 extracellular secretion. The effect of MS-275 on ß1 integrin activity was assessed using specific monoclonal antibodies. The role of Talin-1 in MCs/EOC adhesion was analyzed by genetic silencing. Talin-1 ectopic expression was validated as a rescue tool from MS-275-induced phenotype. The in vivo effect of MS-275-induced MC remodeling was validated in a mouse model of peritoneal EOC dissemination. RESULTS: Treatment of MCs with non-cytotoxic concentrations of MS-275 caused a consistent reduction of EOC adhesion. Proteomic analysis revealed several pathways altered upon MC treatment with MS-275, including ECM deposition/remodeling, adhesion receptors and actin cytoskeleton regulators. HDAC1/2 inhibition hampered actin cytoskeleton polymerization by downregulating actin regulators including Talin-1, impairing ß1 integrin activation, and leading to abnormal extracellular secretion and distribution of Fibronectin-1. Talin-1 ectopic expression rescued EOC adhesion to MS-275-treated MCs. In an experimental mouse model of metastatic EOC, MS-275 limited tumor invasion, Fibronectin-1 secretion and the sub-mesothelial accumulation of MC-derived carcinoma-associated fibroblasts. CONCLUSION: Our study unveils a direct impact of HDAC-1/2 in the regulation of MC/EOC adhesion and highlights the regulation of MC plasticity by epigenetic inhibition as a potential target for therapeutic intervention in EOC peritoneal metastasis.


Asunto(s)
Benzamidas , Carcinoma Epitelial de Ovario , Adhesión Celular , Histona Desacetilasa 1 , Histona Desacetilasa 2 , Neoplasias Ováricas , Neoplasias Peritoneales , Animales , Femenino , Humanos , Ratones , Citoesqueleto de Actina/metabolismo , Anticuerpos Monoclonales , Carcinoma Epitelial de Ovario/metabolismo , Epitelio , Proteínas de la Matriz Extracelular/metabolismo , Fibronectinas , Histona Desacetilasa 1/metabolismo , Integrina alfa5 , Integrina beta1/genética , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Peritoneales/genética , Neoplasias Peritoneales/metabolismo , Proteómica , Piridinas , Talina/genética , Talina/metabolismo , Histona Desacetilasa 2/metabolismo , Adhesión Celular/genética
12.
Physiol Rep ; 12(1): e15897, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38163671

RESUMEN

SLK controls the cytoskeleton, cell adhesion, and migration. Podocyte-specific deletion of SLK in mice leads to podocyte injury as mice age and exacerbates injury in experimental focal segment glomerulosclerosis (FSGS; adriamycin nephrosis). We hypothesized that adhesion proteins may be substrates of SLK. In adriamycin nephrosis, podocyte ultrastructural injury was exaggerated by SLK deletion. Analysis of a protein kinase phosphorylation site dataset showed that podocyte adhesion proteins-paxillin, vinculin, and talin-1 may be potential SLK substrates. In cultured podocytes, deletion of SLK increased adhesion to collagen. Analysis of paxillin, vinculin, and talin-1 showed that SLK deletion reduced focal adhesion complexes (FACs) containing these proteins mainly in adriamycin-induced injury; there was no change in FAC turnover (focal adhesion kinase Y397 phosphorylation). In podocytes, paxillin S250 showed basal phosphorylation that was slightly enhanced by SLK; however, SLK did not phosphorylate talin-1. In adriamycin nephrosis, SLK deletion did not alter glomerular expression/localization of talin-1 and vinculin, but increased focal adhesion kinase phosphorylation modestly. Therefore, SLK decreases podocyte adhesion, but FAC proteins in podocytes are not major substrates of SLK in health and disease.


Asunto(s)
Nefrosis , Podocitos , Ratones , Animales , Podocitos/metabolismo , Paxillin/metabolismo , Vinculina/metabolismo , Talina/genética , Talina/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Doxorrubicina/toxicidad , Proteínas Serina-Treonina Quinasas/metabolismo
13.
Folia Morphol (Warsz) ; 83(1): 92-101, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37144848

RESUMEN

BACKGROUND: The complex process of atherosclerosis is thought to begin with endothelial cell dysfunction, and advanced atherosclerosis is the underlying cause of coronary artery disease (CAD). Uncovering the underlying mechanisms of CAD-related endothelial cell injury may contribute to the treatment. MATERIALS AND METHODS: Cardiac microvascular endothelial cells (CMVECs) were treated with oxidised low-density lipoprotein (ox-LDL) to mimic an injury model. The involvement of Talin-1 (TLN1) and integrin alpha 5 (ITGA5) in the proliferation, apoptosis, angiogenesis, inflammatory response, and oxidative stress in CMVECs were assessed. RESULTS: TLN1 overexpression assisted CMVECs in resistance to ox-LDL stimulation, with alleviated cell proliferation and angiogenesis, reduced apoptosis, inflammatory response, and oxidative stress. TLN1 overexpression triggered increased ITGA5, and ITGA5 knockdown reversed the effects of TLN1 overexpression on the abovementioned aspects. Together, TLN1 synergized with ITGA5 to ameliorate the dysfunction in CMVECs. CONCLUSIONS: This finding suggests their probable involvement in CAD, and increasing their levels is beneficial to disease relief.


Asunto(s)
Aterosclerosis , Células Endoteliales , Humanos , Corazón , Integrinas , Estrés Oxidativo , Talina
14.
Int J Biochem Cell Biol ; 166: 106490, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37914021

RESUMEN

Talin protein (Talin 1/2) is a mechanosensitive cytoskeleton protein. The unique structure of the Talin plays a vital role in transmitting mechanical forces. Talin proteins connect the extracellular matrix to the cytoskeleton by linking to integrins and actin, thereby mediating the conversion of mechanical signals into biochemical signals and influencing disease progression as potential diagnostic indicators, therapeutic targets, and prognostic indicators of various diseases. Most studies in recent years have confirmed that mechanical forces also have a crucial role in the development of disease, and Talin has been found to play a role in several diseases. Still, more studies need to be done on how Talin is involved in mechanical signaling in disease. This review focuses on the mechanical signaling of Talin in disease, aiming to summarize the mechanisms by which Talin plays a role in disease and to provide references for further studies.


Asunto(s)
Mecanotransducción Celular , Talina , Talina/química , Talina/metabolismo , Integrinas/metabolismo , Citoesqueleto/metabolismo , Actinas/metabolismo , Adhesión Celular/fisiología
15.
Nat Struct Mol Biol ; 30(12): 1913-1924, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38087085

RESUMEN

Integrin affinity regulation, also termed integrin activation, is essential for metazoan life. Although talin and kindlin binding to the ß-integrin cytoplasmic tail is indispensable for integrin activation, it is unknown how they achieve this function. By combining NMR, biochemistry and cell biology techniques, we found that talin and kindlin binding to the ß-tail can induce a conformational change that increases talin affinity and decreases kindlin affinity toward it. We also discovered that this asymmetric affinity regulation is accompanied by a direct interaction between talin and kindlin, which promotes simultaneous binding of talin and kindlin to ß-tails. Disrupting allosteric communication between the ß-tail-binding sites of talin and kindlin or their direct interaction in cells severely compromised integrin functions. These data show how talin and kindlin cooperate to generate a small but critical population of ternary talin-ß-integrin-kindlin complexes with high talin-integrin affinity and high dynamics.


Asunto(s)
Integrinas , Talina , Animales , Talina/química , Talina/metabolismo , Integrinas/metabolismo , Sitios de Unión , Unión Proteica
16.
Nat Commun ; 14(1): 8468, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38123541

RESUMEN

Force transmission at integrin-based adhesions is important for cell migration and mechanosensing. Talin is an essential focal adhesion (FA) protein that links F-actin to integrins. F-actin constantly moves on FAs, yet how Talin simultaneously maintains the connection to F-actin and transmits forces to integrins remains unclear. Here we show a critical role of dynamic Talin unfolding in force transmission. Using single-molecule speckle microscopy, we found that the majority of Talin are bound only to either F-actin or the substrate, whereas 4.1% of Talin is linked to both structures via elastic transient clutch. By reconstituting Talin knockdown cells with Talin chimeric mutants, in which the Talin rod subdomains are replaced with the stretchable ß-spectrin repeats, we show that the stretchable property is critical for force transmission. Simulations suggest that unfolding of the Talin rod subdomains increases in the linkage duration and work at FAs. This study elucidates a force transmission mechanism, in which stochastic molecular stretching bridges two cellular structures moving at different speeds.


Asunto(s)
Actinas , Talina , Actinas/metabolismo , Talina/metabolismo , Citoesqueleto de Actina/metabolismo , Integrinas/metabolismo , Adhesiones Focales/metabolismo
17.
PLoS Genet ; 19(12): e1011089, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38150455

RESUMEN

Axon regeneration requires actomyosin interaction, which generates contractile force and pulls the regenerating axon forward. In Caenorhabditis elegans, TLN-1/talin promotes axon regeneration through multiple down-stream events. One is the activation of the PAT-3/integrin-RHO-1/RhoA GTPase-LET-502/ROCK (Rho-associated coiled-coil kinase)-regulatory non-muscle myosin light-chain (MLC) phosphorylation signaling pathway, which is dependent on the MLC scaffolding protein ALP-1/ALP-Enigma. The other is mediated by the F-actin-binding protein DEB-1/vinculin and is independent of the MLC phosphorylation pathway. In this study, we identified the svh-7/rtkn-1 gene, encoding a homolog of the RhoA-binding protein Rhotekin, as a regulator of axon regeneration in motor neurons. However, we found that RTKN-1 does not function in the RhoA-ROCK-MLC phosphorylation pathway in the regulation of axon regeneration. We show that RTKN-1 interacts with ALP-1 and the vinculin-binding protein SORB-1/vinexin, and that SORB-1 acts with DEB-1 to promote axon regeneration. Thus, RTKN-1 links the DEB-1-SORB-1 complex to ALP-1 and physically connects phosphorylated MLC on ALP-1 to the actin cytoskeleton. These results suggest that TLN-1 signaling pathways coordinate MLC phosphorylation and recruitment of phosphorylated MLC to the actin cytoskeleton during axon regeneration.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Talina/metabolismo , Axones/metabolismo , Vinculina , Regeneración Nerviosa/genética , Fosforilación , Quinasas Asociadas a rho/metabolismo , Proteínas de Unión al GTP rho/genética , Proteínas de Unión al GTP rho/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo
18.
Sci Rep ; 13(1): 22368, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102166

RESUMEN

The intestinal immune response is crucial in maintaining a healthy gut, but the enhanced migration of macrophages in response to pathogens is a major contributor to disease pathogenesis. Integrins are ubiquitously expressed cellular receptors that are highly involved in immune cell adhesion to endothelial cells while in the circulation and help facilitate extravasation into tissues. Here we show that specific deletion of the Tln1 gene encoding the protein talin-1, an integrin-activating scaffold protein, from cells of the myeloid lineage using the Lyz2-cre driver mouse reduces epithelial damage, attenuates colitis, downregulates the expression of macrophage markers, decreases the number of differentiated colonic mucosal macrophages, and diminishes the presence of CD68-positive cells in the colonic mucosa of mice infected with the enteric pathogen Citrobacter rodentium. Bone marrow-derived macrophages lacking expression of Tln1 did not exhibit a cell-autonomous phenotype; there was no impaired proinflammatory gene expression, nitric oxide production, phagocytic ability, or surface expression of CD11b, CD86, or major histocompatibility complex II in response to C. rodentium. Thus, we demonstrate that talin-1 plays a role in the manifestation of infectious colitis by increasing mucosal macrophages, with an effect that is independent of macrophage activation.


Asunto(s)
Colitis , Infecciones por Enterobacteriaceae , Animales , Ratones , Citrobacter rodentium , Colitis/genética , Colitis/prevención & control , Colon/patología , Células Endoteliales/metabolismo , Infecciones por Enterobacteriaceae/metabolismo , Inflamación/patología , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Talina/genética , Talina/metabolismo
19.
J Am Chem Soc ; 145(45): 24459-24465, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-38104267

RESUMEN

Light is well-established for control of bond breakage but not for control of specific bond formation in complex environments. We previously engineered the diffusion-limited reactivity of the SpyTag003 peptide with its protein partner SpyCatcher003 through spontaneous isopeptide bond formation. This system enables precise and irreversible assembly of biological building blocks with applications from biomaterials to vaccines. Here we establish a system for the rapid control of this amide bond formation with visible light. We have generated a caged SpyCatcher003, which allows light triggering of covalent bond formation to SpyTag003 in mammalian cells. Photocaging is achieved through site-specific incorporation of an unnatural coumarin-lysine at the reactive site of SpyCatcher003. We showed a uniform specific reaction in cell lysate upon light activation. We then used the spatiotemporal precision of a 405 nm confocal laser for uncaging in seconds, probing the earliest events in mechanotransduction by talin, the key force sensor between the cytoskeleton and the extracellular matrix. Reconstituting talin induced rapid biphasic extension of lamellipodia, revealing the kinetics of talin-regulated cell spreading and polarization. Thereafter we determined the hierarchy of the recruitment of key components for cell adhesion. Precise control over site-specific protein reaction with visible light creates diverse opportunities for cell biology and nanoassembly.


Asunto(s)
Mecanotransducción Celular , Talina , Animales , Adhesión Celular , Talina/metabolismo , Mecanotransducción Celular/fisiología , Citoesqueleto/metabolismo , Microtúbulos/metabolismo , Mamíferos/metabolismo
20.
Cell Rep ; 42(11): 113321, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37874676

RESUMEN

Focal adhesions (FAs) are dynamic protein assemblies that connect cytoskeletons to the extracellular matrix and are crucial for cell adhesion and migration. KANKs are scaffold proteins that encircle FAs and act as key regulators of FA dynamics, but the molecular mechanism underlying their specified localization and functions remains poorly understood. Here, we determine the KANK1 structures in complex with talin and liprin-ß, respectively. These structures, combined with our biochemical and cellular analyses, demonstrate how KANK1 scaffolds the FA core and associated proteins to modulate the FA shape in response to mechanical force. Additionally, we find that KANK1 undergoes liquid-liquid phase separation (LLPS), which is important for its localization at the FA edge and cytoskeleton connections to FAs. Our findings not only indicate the molecular basis of KANKs in bridging the core and periphery of FAs but also provide insights into the LLPS-mediated dynamic regulation of FA morphology.


Asunto(s)
Citoesqueleto , Adhesiones Focales , Adhesiones Focales/metabolismo , Unión Proteica , Adhesión Celular/fisiología , Citoesqueleto/metabolismo , Talina/metabolismo
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