The compass to follow: Focal adhesion turnover

Current Opinion in Cell Biology, Год журнала: 2023, Номер 80, С. 102152 - 102152

Опубликована: Фев. 1, 2023

How cells move is a fundamental biological question. The directionality of adherent migrating depends on the assembly and disassembly (turnover) focal adhesions (FAs). FAs are micron-sized actin-based structures that link to extracellular matrix. Traditionally, microtubules have been considered key triggering FA turnover. Through years, advancements in biochemistry, biophysics, bioimaging tools invaluable for many research groups unravel variety mechanisms molecular players contribute turnover, beyond microtubules. Here, we discuss recent discoveries affect dynamics organization actin cytoskeleton enable timely turnover consequently proper directed cell migration.

Язык: Английский

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Human septins organize as octamer-based filaments and mediate actin-membrane anchoring in cells

The Journal of Cell Biology, Год журнала: 2022, Номер 222(3)

Опубликована: Дек. 23, 2022

Septins are cytoskeletal proteins conserved from algae and protists to mammals. A unique feature of septins is their presence as heteromeric complexes that polymerize into filaments in solution on lipid membranes. Although animal associate extensively with actin-based structures cells, whether organize cells if septin organization impacts function not known. Customizing a tripartite split-GFP complementation assay, we show all decorating actin stress fibers octamer-containing filaments. Depleting octamers or preventing polymerizing leads loss reduced cell stiffness. Super-resolution microscopy revealed widths compatible paired Nanometer-resolved distance measurements single-protein tracking further showed membrane bound largely immobilized. Finally, reconstitution assays mediate actin-membrane anchoring. We propose octamer-based essential for anchoring stabilizing at the plasma membrane.

Язык: Английский

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Septins as membrane influencers: direct play or in association with other cytoskeleton partners

Frontiers in Cell and Developmental Biology, Год журнала: 2023, Номер 11

Опубликована: Фев. 17, 2023

The cytoskeleton comprises three polymerizing structures that have been studied for a long time, actin microfilaments, microtubules and intermediate filaments, plus more recently investigated dynamic assemblies like septins or the endocytic-sorting complex required transport (ESCRT) complex. These filament-forming proteins control several cell functions through crosstalks with each other membranes. In this review, we report recent works address how bind to membranes, influence their shaping, organization, properties functions, either by binding them directly indirectly elements.

Язык: Английский

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The evolutionary origins and ancestral features of septins

Frontiers in Cell and Developmental Biology, Год журнала: 2024, Номер 12

Опубликована: Июнь 26, 2024

Septins are a family of membrane-associated cytoskeletal guanine-nucleotide binding proteins that play crucial roles in various cellular processes, such as cell division, phagocytosis, and organelle fission. Despite their importance, the evolutionary origins ancestral function septins remain unclear. In opisthokonts, form five distinct groups orthologs, with subunits from multiple assembling into heteropolymers, thus supporting diverse molecular functions. Recent studies have revealed also conserved algae protists, indicating an ancient origin last eukaryotic common ancestor. However, phylogenetic relationships among across eukaryotes remained Here, we expanded list non-opisthokont septins, including previously unrecognized glaucophyte algae. Constructing rooted tree 254 total observed bifurcation between major opisthokont septin clades. Within identified three subclades: Group 6 representing chlorophyte green (6A mostly for species single 6B septins), 7 chlorophytes, heterokonts, haptophytes, chrysophytes, rhodophytes, 8 ciliates. Glaucophyte some ciliate formed orphan lineages in-between all other outgroup. Combining ancestral-sequence reconstruction AlphaFold predictions, tracked structural evolution eukaryotes. GTPase domain, GAP-like arginine finger within G-interface at least one most algal species. This residue is required homodimerization Chlamydomonas septin, its loss coincided duplication events lineages. The often accompanied by emergence α0 helix, known NC-interface interaction motif, potentially signifying diversification septin-septin mechanisms homo-dimerization to hetero-oligomerization. Lastly, found amphipathic helices groups, suggesting membrane trait. Coiled-coil domains were broadly distributed, while transmembrane 6A 7. summary, this study advances our understanding distribution groupings, shedding light on features, potential function, early evolution.

Язык: Английский

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Lysyl hydroxylase LH1 promotes confined migration and metastasis of cancer cells by stabilizing Septin2 to enhance actin network

Molecular Cancer, Год журнала: 2023, Номер 22(1)

Опубликована: Янв. 31, 2023

Abstract Background Excessive extracellular matrix deposition and increased stiffness are typical features of solid tumors such as hepatocellular carcinoma (HCC) pancreatic ductal adenocarcinoma (PDAC). These conditions create confined spaces for tumor cell migration metastasis. The regulatory mechanism remains unclear. Methods LC–MS was applied to determine the differentially expressed proteins between HCC tissues corresponding adjacent tissue. Collective single microfluidic devices with 6 μm-high channels were designed fabricated mimic in vivo space. 3D invasion assay created by Matrigel Collagen I mixture treat adherent cells. spheroid formation under various environment developed different substitution percentage GelMA. Immunoprecipitation performed pull down LH1-binding proteins, which identified LC–MS. Immunofluorescent staining, FRET, RT-PCR, Western blotting, FRAP, CCK-8, transwell migration, wound healing, orthotopic liver injection mouse model imaging used evaluate target expression cellular phenotype. Results Lysyl hydroxylase 1 (LH1) promoted cancer cells at both collective levels. In addition, LH1 enhanced a biomimetic stiffer environments. High correlated poor prognosis PDAC patients, while it also Mechanistically, bound stabilized Septin2 (SEPT2) enhance actin polymerization, depending on domain. Finally, subpopulation high SEPT2 had poorest prognosis. Conclusions promotes metastasis stabilizing thus facilitating polymerization.

Язык: Английский

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Thy-1 (CD90)-regulated cell adhesion and migration of mesenchymal cells: insights into adhesomes, mechanical forces, and signaling pathways

Frontiers in Cell and Developmental Biology, Год журнала: 2023, Номер 11

Опубликована: Ноя. 30, 2023

Cell adhesion and migration depend on the assembly disassembly of adhesive structures known as focal adhesions. Cells adhere to extracellular matrix (ECM) form these via receptors, such integrins syndecans, which initiate signal transduction pathways that bridge ECM cytoskeleton, thus governing processes. Integrins bind soluble or cell surface ligands integrin complexes (IAC), whose composition depends cellular context type. Proteomic analyses IACs led curation term adhesome, is a complex molecular network containing hundreds proteins involved in signaling, adhesion, movement. One hallmarks sense mechanical cues arise due rigidity, well tension exerted by cell-cell interactions, transduce this force modifying actin cytoskeleton regulate migration. Among integrin/syndecan ligands, we have described Thy-1 (CD90), GPI-anchored protein possesses binding domains for each receptors and, upon engaging them, stimulates In review, examine what currently about adhesomes, revise how forces changed our view regulation migration, context, discuss contributed understanding signaling mechanisms control

Язык: Английский

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Chemical Proteomics Reveals Nε-Fatty-Acylation of Septins by Rho Inactivation Domain (RID) of the Vibrio MARTX Toxin to Alter Septin Localization and Organization

Molecular & Cellular Proteomics, Год журнала: 2024, Номер 23(3), С. 100730 - 100730

Опубликована: Фев. 2, 2024

Vibrio species, the Gram-negative bacterial pathogens causing cholera and sepsis, produce multiple secreted virulence factors for infection pathogenesis. Among these is multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin that releases several critical effector domains with distinct functions inside eukaryotic host cells. One such domain, Rho inactivation domain (RID), has been discovered to catalyze long-chain N

Язык: Английский

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Septin-3 autoimmunity in patients with paraneoplastic cerebellar ataxia

Journal of Neuroinflammation, Год журнала: 2023, Номер 20(1)

Опубликована: Март 30, 2023

Septins are cytoskeletal proteins with filament forming capabilities, which have multiple roles during cell division, cellular polarization, morphogenesis, and membrane trafficking. Autoantibodies against septin-5 associated non-paraneoplastic cerebellar ataxia, autoantibodies septin-7 encephalopathy prominent neuropsychiatric features. Here, we report on newly identified septin-3 in patients paraneoplastic ataxia. We also propose a strategy for anti-septin autoantibody determination.Sera from three producing similar immunofluorescence staining patterns hippocampal sections were subjected to immunoprecipitation followed by mass spectrometry. The candidate antigens, all of septins, expressed recombinantly HEK293 cells either individually, as complexes, or combinations missing individual use recombinant cell-based indirect assays (RC-IIFA). Specificity was further confirmed tissue IIFA neutralization experiments. Finally, tumor analyzed immunohistochemically expression.Immunoprecipitation rat cerebellum lysate revealed septin-3, -5, -6, -7, -11 target antigens. Sera reacted co-expressing septin-3/5/6/7/11, while none 149 healthy control sera similarly reactive. In RC-IIFAs the patient recognized only expressing individually complexes. Incubation five different septin combinations, each one autoantibodies' specificity septin-3. reactivity serum abolished pre-incubation lysates overexpressing septin-3/5/6/7/11 complex alone, but not control. All had cancers (2 × melanoma, 1 small lung cancer), presented progressive syndromes, responded poorly immunotherapy. Expression demonstrated resected available patient.Septin-3 is novel syndromes. Based our findings, RC-IIFA may serve screening tool investigate serological samples characteristic pattern neuronal sections. septins can then be single septins.

Язык: Английский

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The structure of a tetrameric septin complex reveals a hydrophobic element essential for NC-interface integrity

Communications Biology, Год журнала: 2024, Номер 7(1)

Опубликована: Янв. 6, 2024

Abstract The septins of the yeast Saccharomyces cerevisiae assemble into hetero-octameric rods by alternating interactions between neighboring G-domains or N- and C-termini, respectively. These polymerize end to apolar filaments, forming a ring beneath prospective new bud that expands during cell cycle an hourglass structure. finally splits cytokinesis double ring. Understanding these transitions as well plasticity higher order assemblies requires detailed knowledge underlying structures. Here we present first X-ray crystal structure tetrameric Shs1-Cdc12-Cdc3-Cdc10 complex at resolution 3.2 Å. Close inspection NC-interfaces this other septin structures reveals conserved contact motif is essential for NC-interface integrity human in vivo vitro. Using combination with AlphaFold-Multimer allowed us propose model octameric rod.

Язык: Английский

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Two Septin complexes mediate actin dynamics during cell wound repair

Cell Reports, Год журнала: 2024, Номер 43(5), С. 114215 - 114215

Опубликована: Май 1, 2024

Cells have robust wound repair systems to prevent further damage or infection and quickly restore cell cortex integrity when exposed mechanical chemical stress. Actomyosin ring formation contraction at the edge are major events during closure of plasma membrane underlying cytoskeleton repair. Here, we show that all five Drosophila Septins required for efficient Based on their different recruitment patterns knockdown/mutant phenotypes, two distinct Septin complexes, Sep1/Sep2/Pnut Sep4/Sep5/Pnut, assembled regulate actin assembly, contraction, remodeling process. Intriguingly, find these complexes F-actin bending activities. In addition, Anillin regulates only one upon wounding. Our results demonstrate functionally work side by discretely actomyosin dynamics

Язык: Английский

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