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Jonathan C. R. Jones - One of the best experts on this subject based on the ideXlab platform.
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Hemidesmosomes and focal contact proteins: Functions and cross-talk in keratinocytes, bullous diseases and wound healing
Journal of Dermatological Science, 2011Co-Authors: Daisuke Tsuruta, Takashi Hashimoto, Kevin J. Hamill, Jonathan C. R. JonesAbstract:The outer most layer of the skin, the epidermis, is attached to the dermis via a sheet of extracellular matrix proteins termed the basement membrane zone (BMZ). In the intact skin, adhesion of the keratinocytes in the basal layer of the epidermis to the BMZ is facilitated primarily by Hemidesmosomes which associate with the keratin cytoskeleton. Cultured keratinocytes do not assemble bona fide Hemidesmosomes although Hemidesmosome protein clusters (stable anchoring contacts) are found along the substrate-attached surface of the cells and towards the leading edge of keratinocytes repopulating scratch wounds. Actin cytoskeleton-associated matrix adhesion devices termed focal contacts are not thought to play an important role in the adhesion of keratinocytes to the BMZ in intact skin but are prominent in cultured keratinocytes where they are believed to regulate cell migration. We review the molecular components, functions, dynamics and cross-talk of Hemidesmosomes and focal contacts in keratinocytes. In addition, we briefly describe what is known about their role in autoimmune and genetic blistering diseases of the skin. We also discuss recent publications which indicate, contrary to expectation, that certain focal contact proteins retard keratinocyte migration while hemidesmosomal proteins regulate directed keratinocyte motility during wound healing.
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dynamic relationship of focal contacts and Hemidesmosome protein complexes in live cells
Journal of Investigative Dermatology, 2010Co-Authors: Toshiyuki Ozawa, Jonathan C. R. Jones, Daisuke Tsuruta, Masamitsu Ishii, Kazuo Ikeda, Teruichi Harada, Yumi Aoyama, Akira Kawada, Hiromi KobayashiAbstract:Epidermal cells adhere to the basement membrane zone through cell–matrix junctions termed Hemidesmosomes. During wound healing, Hemidesmosomes are disassembled to allow keratinocytes to move over wound sites. Such movement is mediated by both Hemidesmosome protein complexes (HPCs) and focal contacts (FCs). In this study, we analyzed the interaction between HPCs and FCs in live HaCat cells expressing yellow fluorescent protein (YFP)-tagged β4 integrin and cyan fluorescent protein (CFP)-tagged α-actinin as markers of HPCs and FCs, respectively. In HaCat cells migrating to repopulate wounds, FC proteins cluster rapidly in the direction of the wound. HPC assembly then follows and the newly formed HPCs occupy sites vacated by the disassembled FCs. HPC dynamics are dramatically reduced, and HaCat cells cease migration upon treatment with reagents that affect FC integrity/function. Upon treatment with reagents that destabilize HPCs, the dynamics of FCs in HaCat cells at the edges of wounds are enhanced, although FC assembly is irregular and the migration of the cells is aberrant. We also show that the complex interaction between Hemidesmosomes and FCs in keratinocytes is myosin dependent and requires energy. In summary, we suggest that HPCs and FCs dynamics are tightly co-regulated in keratinocytes undergoing migration during wound healing.
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Hemidesmosome protein dynamics in live epithelial cells
Cytoskeleton, 2003Co-Authors: Daisuke Tsuruta, Susan B Hopkinson, Jonathan C. R. JonesAbstract:Hemidesmosomes mediate stable anchorage of epithelial cells to laminin-5 in the basement membrane zone and have been likened to spot-welds. Indeed, it has been assumed that Hemidesmosomes are not dynamic, at least when compared to other matrix adhesion sites including focal contacts. We tested this notion by monitoring the fate of green fluorescent protein (GFP)-tagged human integrin β4 subunit (GFP-hβ4) and GFP-tagged 180-kD human bullous pemphigoid (BP) autoantigen (GFP-BP180) in live cultures of 804G cells that assemble numerous mature Hemidesmosomes. In subconfluent 804G cells, both GFP-hβ4 and GFP-BP180 protein clusters are not stable but assemble into and disassemble out of cat paw–like arrays at a relatively rapid rate. In confluent populations of 804G cells, although some cat paw–like clusters of both GFP-hβ4 and GFP-BP180 are stable over periods of >60 min, other GFP-hβ4 and GFP-BP180 protein arrays form and/or disappear during the same time period. Moreover, individual labeled particles show considerable motility in the plane of the membrane. Fluorescence recovery after photobleaching analyses provide a further indication of the dynamics of Hemidesmosome proteins. In particular, bleached GFP-hβ4 protein clusters in confluent cells recover signal within about 30 min, indicating that there is a relatively rapid turnover of Hemidesmosome components in protein arrays clustered along the substratum attached surface of a cell. The rate of recovery is dependent on an intact microfilament system. In sharp contrast, bleached GFP-BP180 protein clusters in confluent cells fail to recover signal even when observed for longer than 60 min. To evaluate Hemidesmosome protein dynamics in motile cells, we monitored GFP-hβ4 and GFP-BP180 in 804G cells populating scrape wound sites in vitro. In these migratory cells, which lack mature Hemidesmosomes, integrin β4 subunit and BP180 protein clusters progressively assemble and disassemble into linear and cat-paw arrays. In summary, Hemidesmosome protein clusters, like their counterparts in focal contacts, are dynamic. We discuss these results in relation to Hemidesmosome functions. Cell Motil. Cytoskeleton 54:122–134, 2003. © 2003 Wiley-Liss, Inc.
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the n terminus of the transmembrane protein bp180 interacts with the n terminal domain of bp230 thereby mediating keratin cytoskeleton anchorage to the cell surface at the site of the Hemidesmosome
Molecular Biology of the Cell, 2000Co-Authors: Susan B Hopkinson, Jonathan C. R. JonesAbstract:In epidermal cells, the keratin cytoskeleton interacts with the elements in the basement membrane via a multimolecular junction called the Hemidesmosome. A major component of the Hemidesmosome plaque is the 230-kDa bullous pemphigoid autoantigen (BP230/BPAG1), which connects directly to the keratin-containing intermediate filaments of the cytoskeleton via its C terminus. A second bullous pemphigoid antigen of 180 kDa (BP180/BPAG2) is a type II transmembrane component of the Hemidesmosome. Using yeast two-hybrid technology and recombinant proteins, we show that an N-terminal fragment of BP230 can bind directly to an N-terminal fragment of BP180. We have also explored the consequences of expression of the BP230 N terminus in 804G cells that assemble Hemidesmosomes in vitro. Unexpectedly, this fragment disrupts the distribution of BP180 in transfected cells but has no apparent impact on the organization of endogenous BP230 and α6β4 integrin. We propose that the BP230 N terminus competes with endogenous BP230 protein for BP180 binding and inhibits incorporation of BP180 into the cell surface at the site of the Hemidesmosome. These data provide new insight into those interactions of the molecules of the Hemidesmosome that are necessary for its function in integrating epithelial and connective tissue types.
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Original ArticleInteraction of BP180 (Type XVII Collagen) and α6 Integrin is Necessary for Stabilization of Hemidesmosome Structure
Journal of Investigative Dermatology, 1998Co-Authors: Susan B Hopkinson, Kirk Findlay, Gregory W Dehart, Jonathan C. R. JonesAbstract:The Hemidesmosome is a multimolecular complex that integrates the extracellular matrix with the keratin cytoskeleton and that stabilizes epithelial attachment to connective tissue. A 180 kDa protein (BP180, type XVII collagen), first identified by its reactivity with autoantibodies in the serum of patients with a blistering skin disease called bullous pemphigoid (BP), is a transmembrane component of the Hemidesmosome with a collagen-like extracellular domain. Here, using recombinantly expressed molecules and the yeast two-hybrid assay, we have identified α6 integrin as a BP180-binding partner. The association between specific domains of the BP180 and α6 integrin molecules is inhibited by a 14 mer peptide, whose sequence is identical to amino acid residues 506–519 in the noncollagenous region of the ectodomain of the BP180 molecule, as well as by antibodies raised against this peptide. The 14 mer peptide sequence is part of an epitope recognized by autoantibodies that are pathogenic in BP.In vivo, when 804G cells are plated into medium containing the same peptide, they fail to assemble Hemidesmosomes. Furthermore, although BP180 and certain cytoplasmic components of the Hemidesmosome colocalize in the peptide-treated cells, they are aberrantly distributed and fail to show extensive association with α6β4 integrin. Taken together, our results indicate that BP180 is a novel transmembrane ligand of the α6β4 integrin heterodimer. In addition, our data provide support for the possibility that BP180 and α6 integrin interaction is not only mediated by the BP epitope but is necessary for Hemidesmosome formation.
Huimin Zhang - One of the best experts on this subject based on the ideXlab platform.
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CCAR-1 affects Hemidesmosome biogenesis by regulating unc-52/perlecan alternative splicing in the C. elegans epidermis.
Journal of Cell Science, 2018Co-Authors: Rong Fu, Michel Labouesse, Xiaowan Jiang, Yuanbao Li, Mengqiu Dong, Zhaohui Huang, Chunxia Wang, Huimin ZhangAbstract:ABSTRACT Hemidesmosomes are epithelial-specific attachment structures that maintain tissue integrity and resist tension. Despite their importance, how Hemidesmosomes are regulated at the post-transcriptional level is poorly understood. Caenorhabditis elegans Hemidesmosomes (CeHDs) have a similar structure and composition to their mammalian counterparts, making C. elegans an ideal model for studying Hemidesmosomes. Here, we focus on the transcription regulator CCAR-1, identified in a previous genetic screen searching for enhancers of mutations in the conserved Hemidesmosome component VAB-10A (known as plectin in mammals). Loss of CCAR-1 function in a vab-10(e698) background results in CeHD disruption and muscle detachment from the epidermis. CCAR-1 regulates CeHD biogenesis, not by controlling the transcription of CeHD-related genes, but by affecting the alternative splicing of unc-52 (known as perlecan or HSPG2 in mammals), the predicted basement extracellular matrix (ECM) ligand of CeHDs. CCAR-1 physically interacts with HRP-2 (hnRNPR in mammals), a splicing factor known to mediate unc-52 alternative splicing to control the proportions of different UNC-52 isoforms and stabilize CeHDs. Our discovery underlines the importance of post-transcriptional regulation in Hemidesmosome reorganization. It also uncovers previously unappreciated roles of CCAR-1 in alternative splicing and Hemidesmosome biogenesis, shedding new light on the mechanisms through which mammalian CCAR1 functions in tumorigenesis.
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ccar 1 affects Hemidesmosome biogenesis by regulating unc 52 perlecan alternative splicing in the c elegans epidermis
Journal of Cell Science, 2018Co-Authors: Rong Fu, Michel Labouesse, Xiaowan Jiang, Yuanbao Li, Mengqiu Dong, Zhaohui Huang, Chunxia Wang, Huimin ZhangAbstract:ABSTRACT Hemidesmosomes are epithelial-specific attachment structures that maintain tissue integrity and resist tension. Despite their importance, how Hemidesmosomes are regulated at the post-transcriptional level is poorly understood. Caenorhabditis elegans Hemidesmosomes (CeHDs) have a similar structure and composition to their mammalian counterparts, making C. elegans an ideal model for studying Hemidesmosomes. Here, we focus on the transcription regulator CCAR-1, identified in a previous genetic screen searching for enhancers of mutations in the conserved Hemidesmosome component VAB-10A (known as plectin in mammals). Loss of CCAR-1 function in a vab-10(e698) background results in CeHD disruption and muscle detachment from the epidermis. CCAR-1 regulates CeHD biogenesis, not by controlling the transcription of CeHD-related genes, but by affecting the alternative splicing of unc-52 (known as perlecan or HSPG2 in mammals), the predicted basement extracellular matrix (ECM) ligand of CeHDs. CCAR-1 physically interacts with HRP-2 (hnRNPR in mammals), a splicing factor known to mediate unc-52 alternative splicing to control the proportions of different UNC-52 isoforms and stabilize CeHDs. Our discovery underlines the importance of post-transcriptional regulation in Hemidesmosome reorganization. It also uncovers previously unappreciated roles of CCAR-1 in alternative splicing and Hemidesmosome biogenesis, shedding new light on the mechanisms through which mammalian CCAR1 functions in tumorigenesis.
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a tension induced mechanotransduction pathway promotes epithelial morphogenesis
Nature, 2011Co-Authors: Huimin Zhang, Hala Zahreddine, Marc Koch, Frédéric Landmann, David Rodriguez, Michel LabouesseAbstract:The development and function of many organs depend not only on biochemical signals, but also on the ability of cells and tissues to respond biochemically to mechanical forces — mechanotransduction. Here, Michel Labouesse and colleagues describe a mechanotransduction pathway that links the body wall with the epidermis in the roundworm Caenorhabditis elegans. The pathway involves the p21-activated kinase PAK-1, an adaptor GIT-1 and its partner PIX-1. Tension exerted by muscles or external pressure keeps GIT-1 on station at Hemidesmosomes — the small rivet-like bodies that attach epidermal cells to the underlying musculature — and stimulates PAK-1 through PIX-1 and Rac GTPase. The C. elegans Hemidesmosome is therefore more than a passive attachment structure — it is a sensor that responds to tension by triggering signalling processes. This study describes a mechanotransduction pathway that links the body wall with the epidermis in Caenorhabditis elegans. The pathway involves the p21 activated kinase PAK 1, an adaptor GIT 1 and its partner PIX 1. Tension exerted by muscles or external pressure keeps GIT 1 on station at Hemidesmosomes — the small rivet like bodies that attach epidermal cells to the underlying musculature — and stimulates PAK 1 through PIX 1 and Rac GTPase. The C. elegans Hemidesmosome is more than a passive attachment structure, therefore, but a sensor that responds to tension by triggering signalling processes. Mechanotransduction refers to the transformation of physical forces into chemical signals. It generally involves stretch-sensitive channels or conformational change of cytoskeleton-associated proteins1. Mechanotransduction is crucial for the physiology of several organs and for cell migration2,3. The extent to which mechanical inputs contribute to development, and how they do this, remains poorly defined. Here we show that a mechanotransduction pathway operates between the body-wall muscles of Caenorhabditis elegans and the epidermis. This pathway involves, in addition to a Rac GTPase, three signalling proteins found at the Hemidesmosome: p21-activated kinase (PAK-1), the adaptor GIT-1 and its partner PIX-1. The phosphorylation of intermediate filaments is one output of this pathway. Tension exerted by adjacent muscles or externally exerted mechanical pressure maintains GIT-1 at Hemidesmosomes and stimulates PAK-1 activity through PIX-1 and Rac. This pathway promotes the maturation of a Hemidesmosome into a junction that can resist mechanical stress and contributes to coordinating the morphogenesis of epidermal and muscle tissues. Our findings suggest that the C. elegans Hemidesmosome is not only an attachment structure, but also a mechanosensor that responds to tension by triggering signalling processes. We suggest that similar pathways could promote epithelial morphogenesis or wound healing in other organisms in which epithelial cells adhere to tension-generating contractile cells.
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the making of Hemidesmosome structures in vivo
Developmental Dynamics, 2010Co-Authors: Huimin Zhang, Michel LabouesseAbstract:Hemidesmosomes are evolutionarily conserved attachment complexes linked to intermediate filaments that connect epithelial cells to the extracellular matrix. They provide tissue integrity and resistance to mechanical forces. Alterations in Hemidesmosome structures are responsible for skin blistering, carcinoma invasion, and wound-healing defects. Valuable information about Hemidesmosome assembly and disassembly has been obtained from in vitro cell culture studies. However, how these processes take place in vivo still remains elusive. Here, we discuss recent data about the formation and reorganization of Hemidesmosomes in several in vivo model systems, particularly zebrafish and Caenorhabditis elegans, focusing on various factors affecting their dynamics. Mechanisms found in different organisms reveal that Hemidesmosome formation and maintenance in vivo are carefully controlled by ECM protein folding, ECM-receptor expression and trafficking, and by post-translational modification of Hemidesmosome components. These findings validate and extend the in vitro studies, and shed light on our understanding about Hemidesmosomes across species. Developmental Dynamics 239:1465–1476, 2010. © 2010 Wiley-Liss, Inc.
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crt 1 calreticulin and the e3 ligase eel 1 huwe1 control Hemidesmosome maturation in c elegans development
Current Biology, 2010Co-Authors: Hala Zahreddine, Huimin Zhang, Marie Diogon, Yasuko Nagamatsu, Michel LabouesseAbstract:Summary Hemidesmosomes connect the extracellular matrix (ECM) to intermediate filaments through ECM receptors and plakins (plectin and BPAG1e). They affect tissue integrity, wound healing, and carcinoma invasion [1]. Although biochemical and time-lapse studies indicate that α6β4-integrin (ECM receptor) and plectin play a central role in modulating Hemidesmosome disassembly [2–5], the mechanisms controlling Hemidesmosome biogenesis in vivo remain poorly understood. The nematode C. elegans provides a powerful genetic model to address this issue. We performed a genome-wide RNA interference screen in C. elegans , searching for genes that decrease the viability of a weak VAB-10A/plakin mutant. We identified 14 genes that have human homologs with predicted roles in different cellular processes. We further characterized two genes encoding the chaperone CRT-1/calreticulin and the HECT domain E3 ubiquitin ligase EEL-1/HUWE1. CRT-1 controls by as little as 2-fold the abundance of UNC-52/perlecan, an essential Hemidesmosome ECM ligand. Likewise, EEL-1 fine tunes by 2-fold the abundance of myotactin, the putative Hemidesmosome ECM receptor. CRT-1 and EEL-1 activities, and by extension other genes identified in our screen, are essential during embryonic development to enable Hemidesmosomes exposed to mechanical tension to mature into a tension-resistant form. Our findings should help understand how Hemidesmosome dynamics are regulated in vertebrate systems.
Michel Labouesse - One of the best experts on this subject based on the ideXlab platform.
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CCAR-1 affects Hemidesmosome biogenesis by regulating unc-52/perlecan alternative splicing in the C. elegans epidermis.
Journal of Cell Science, 2018Co-Authors: Rong Fu, Michel Labouesse, Xiaowan Jiang, Yuanbao Li, Mengqiu Dong, Zhaohui Huang, Chunxia Wang, Huimin ZhangAbstract:ABSTRACT Hemidesmosomes are epithelial-specific attachment structures that maintain tissue integrity and resist tension. Despite their importance, how Hemidesmosomes are regulated at the post-transcriptional level is poorly understood. Caenorhabditis elegans Hemidesmosomes (CeHDs) have a similar structure and composition to their mammalian counterparts, making C. elegans an ideal model for studying Hemidesmosomes. Here, we focus on the transcription regulator CCAR-1, identified in a previous genetic screen searching for enhancers of mutations in the conserved Hemidesmosome component VAB-10A (known as plectin in mammals). Loss of CCAR-1 function in a vab-10(e698) background results in CeHD disruption and muscle detachment from the epidermis. CCAR-1 regulates CeHD biogenesis, not by controlling the transcription of CeHD-related genes, but by affecting the alternative splicing of unc-52 (known as perlecan or HSPG2 in mammals), the predicted basement extracellular matrix (ECM) ligand of CeHDs. CCAR-1 physically interacts with HRP-2 (hnRNPR in mammals), a splicing factor known to mediate unc-52 alternative splicing to control the proportions of different UNC-52 isoforms and stabilize CeHDs. Our discovery underlines the importance of post-transcriptional regulation in Hemidesmosome reorganization. It also uncovers previously unappreciated roles of CCAR-1 in alternative splicing and Hemidesmosome biogenesis, shedding new light on the mechanisms through which mammalian CCAR1 functions in tumorigenesis.
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ccar 1 affects Hemidesmosome biogenesis by regulating unc 52 perlecan alternative splicing in the c elegans epidermis
Journal of Cell Science, 2018Co-Authors: Rong Fu, Michel Labouesse, Xiaowan Jiang, Yuanbao Li, Mengqiu Dong, Zhaohui Huang, Chunxia Wang, Huimin ZhangAbstract:ABSTRACT Hemidesmosomes are epithelial-specific attachment structures that maintain tissue integrity and resist tension. Despite their importance, how Hemidesmosomes are regulated at the post-transcriptional level is poorly understood. Caenorhabditis elegans Hemidesmosomes (CeHDs) have a similar structure and composition to their mammalian counterparts, making C. elegans an ideal model for studying Hemidesmosomes. Here, we focus on the transcription regulator CCAR-1, identified in a previous genetic screen searching for enhancers of mutations in the conserved Hemidesmosome component VAB-10A (known as plectin in mammals). Loss of CCAR-1 function in a vab-10(e698) background results in CeHD disruption and muscle detachment from the epidermis. CCAR-1 regulates CeHD biogenesis, not by controlling the transcription of CeHD-related genes, but by affecting the alternative splicing of unc-52 (known as perlecan or HSPG2 in mammals), the predicted basement extracellular matrix (ECM) ligand of CeHDs. CCAR-1 physically interacts with HRP-2 (hnRNPR in mammals), a splicing factor known to mediate unc-52 alternative splicing to control the proportions of different UNC-52 isoforms and stabilize CeHDs. Our discovery underlines the importance of post-transcriptional regulation in Hemidesmosome reorganization. It also uncovers previously unappreciated roles of CCAR-1 in alternative splicing and Hemidesmosome biogenesis, shedding new light on the mechanisms through which mammalian CCAR1 functions in tumorigenesis.
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a tension induced mechanotransduction pathway promotes epithelial morphogenesis
Nature, 2011Co-Authors: Huimin Zhang, Hala Zahreddine, Marc Koch, Frédéric Landmann, David Rodriguez, Michel LabouesseAbstract:The development and function of many organs depend not only on biochemical signals, but also on the ability of cells and tissues to respond biochemically to mechanical forces — mechanotransduction. Here, Michel Labouesse and colleagues describe a mechanotransduction pathway that links the body wall with the epidermis in the roundworm Caenorhabditis elegans. The pathway involves the p21-activated kinase PAK-1, an adaptor GIT-1 and its partner PIX-1. Tension exerted by muscles or external pressure keeps GIT-1 on station at Hemidesmosomes — the small rivet-like bodies that attach epidermal cells to the underlying musculature — and stimulates PAK-1 through PIX-1 and Rac GTPase. The C. elegans Hemidesmosome is therefore more than a passive attachment structure — it is a sensor that responds to tension by triggering signalling processes. This study describes a mechanotransduction pathway that links the body wall with the epidermis in Caenorhabditis elegans. The pathway involves the p21 activated kinase PAK 1, an adaptor GIT 1 and its partner PIX 1. Tension exerted by muscles or external pressure keeps GIT 1 on station at Hemidesmosomes — the small rivet like bodies that attach epidermal cells to the underlying musculature — and stimulates PAK 1 through PIX 1 and Rac GTPase. The C. elegans Hemidesmosome is more than a passive attachment structure, therefore, but a sensor that responds to tension by triggering signalling processes. Mechanotransduction refers to the transformation of physical forces into chemical signals. It generally involves stretch-sensitive channels or conformational change of cytoskeleton-associated proteins1. Mechanotransduction is crucial for the physiology of several organs and for cell migration2,3. The extent to which mechanical inputs contribute to development, and how they do this, remains poorly defined. Here we show that a mechanotransduction pathway operates between the body-wall muscles of Caenorhabditis elegans and the epidermis. This pathway involves, in addition to a Rac GTPase, three signalling proteins found at the Hemidesmosome: p21-activated kinase (PAK-1), the adaptor GIT-1 and its partner PIX-1. The phosphorylation of intermediate filaments is one output of this pathway. Tension exerted by adjacent muscles or externally exerted mechanical pressure maintains GIT-1 at Hemidesmosomes and stimulates PAK-1 activity through PIX-1 and Rac. This pathway promotes the maturation of a Hemidesmosome into a junction that can resist mechanical stress and contributes to coordinating the morphogenesis of epidermal and muscle tissues. Our findings suggest that the C. elegans Hemidesmosome is not only an attachment structure, but also a mechanosensor that responds to tension by triggering signalling processes. We suggest that similar pathways could promote epithelial morphogenesis or wound healing in other organisms in which epithelial cells adhere to tension-generating contractile cells.
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pat 12 a potential anti nematode target is a new spectraplakin partner essential for caenorhabditis elegans Hemidesmosome integrity and embryonic morphogenesis
Developmental Biology, 2011Co-Authors: Hala Zahreddine, Suzannah Hetherington, Christelle Gally, Julieanne Fritz, Jolanta Polanowska, Jerome Reboul, Yannick Schwab, Carolyn A Behm, Michel LabouesseAbstract:Abstract Caenorhabditis elegans embryonic elongation depends on both epidermal and muscle cells. The Hemidesmosome-like junctions, commonly called fibrous organelles (FOs), that attach the epidermis to the extracellular matrix ensure muscle anchoring to the cuticular exoskeleton and play an essential role during elongation. To further define how Hemidesmosomes might control elongation, we searched for factors interacting with the core Hemidesmosome component, the spectraplakin homolog VAB-10. Using the VAB-10 plakin domain as bait in a yeast two-hybrid screen, we identified the novel protein T17H7.4. We also identified T17H7.4 in an independent bioinformatic search for essential nematode-specific proteins that could define novel anti-nematode drug or vaccine targets. Interestingly, T17H7.4 corresponds to the C. elegans equivalent of the parasitic OvB20 antigen, and has a characteristic Hemidesmosome distribution. We identified two mutations in T17H7.4, one of which defines the uncharacterized gene pat-12, previously identified in screens for genes required for muscle assembly. Using isoform-specific GFP constructs, we showed that one pat-12 isoform with a Hemidesmosome distribution can rescue a pat-12 null allele. We further found that lack of pat-12 affects Hemidesmosome integrity, with marked defects at the apical membrane. PAT-12 defines a novel component of C. elegans Hemidesmosomes, which is required for maintaining their integrity. We suggest that PAT-12 helps maintaining VAB-10 attachment with matrix receptors.
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the making of Hemidesmosome structures in vivo
Developmental Dynamics, 2010Co-Authors: Huimin Zhang, Michel LabouesseAbstract:Hemidesmosomes are evolutionarily conserved attachment complexes linked to intermediate filaments that connect epithelial cells to the extracellular matrix. They provide tissue integrity and resistance to mechanical forces. Alterations in Hemidesmosome structures are responsible for skin blistering, carcinoma invasion, and wound-healing defects. Valuable information about Hemidesmosome assembly and disassembly has been obtained from in vitro cell culture studies. However, how these processes take place in vivo still remains elusive. Here, we discuss recent data about the formation and reorganization of Hemidesmosomes in several in vivo model systems, particularly zebrafish and Caenorhabditis elegans, focusing on various factors affecting their dynamics. Mechanisms found in different organisms reveal that Hemidesmosome formation and maintenance in vivo are carefully controlled by ECM protein folding, ECM-receptor expression and trafficking, and by post-translational modification of Hemidesmosome components. These findings validate and extend the in vitro studies, and shed light on our understanding about Hemidesmosomes across species. Developmental Dynamics 239:1465–1476, 2010. © 2010 Wiley-Liss, Inc.
Arnoud Sonnenberg - One of the best experts on this subject based on the ideXlab platform.
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Hemidesmosomes modulate force generation via focal adhesions.
Journal of Cell Biology, 2020Co-Authors: Wei Wang, Leila Nahidiazar, Alba Zuidema, Lisa Te Molder, Liesbeth Hoekman, Thomas Schmidt, Stefano Coppola, Arnoud SonnenbergAbstract:: Hemidesmosomes are specialized cell-matrix adhesion structures that are associated with the keratin cytoskeleton. Although the adhesion function of Hemidesmosomes has been extensively studied, their role in mechanosignaling and transduction remains largely unexplored. Here, we show that keratinocytes lacking hemidesmosomal integrin α6β4 exhibit increased focal adhesion formation, cell spreading, and traction-force generation. Moreover, disruption of the interaction between α6β4 and intermediate filaments or laminin-332 results in similar phenotypical changes. We further demonstrate that integrin α6β4 regulates the activity of the mechanosensitive transcriptional regulator YAP through inhibition of Rho-ROCK-MLC- and FAK-PI3K-dependent signaling pathways. Additionally, increased tension caused by impaired Hemidesmosome assembly leads to a redistribution of integrin αVβ5 from clathrin lattices to focal adhesions. Our results reveal a novel role for Hemidesmosomes as regulators of cellular mechanical forces and establish the existence of a mechanical coupling between adhesion complexes.
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Integrin α6β4 Recognition of a Linear Motif of Bullous Pemphigoid Antigen BP230 Controls Its Recruitment to Hemidesmosomes.
Structure, 2019Co-Authors: José A. Manso, Arnoud Sonnenberg, Maaike Kreft, María Teresa Gómez-hernández, Arturo Carabias, Noelia Alonso-garcía, Inés García-rubio, José M. De PeredaAbstract:Summary Mechanical stability of epithelia requires firm attachment to the basement membrane via Hemidesmosomes. Dysfunction of hemidesmosomal proteins causes severe skin-blistering diseases. Two plakins, plectin and BP230 (BPAG1e), link the integrin α6β4 to intermediate filaments in epidermal Hemidesmosomes. Here, we show that a linear sequence within the isoform-specific N-terminal region of BP230 binds to the third and fourth FnIII domains of β4. The crystal structure of the complex and mutagenesis analysis revealed that BP230 binds between the two domains of β4. BP230 induces closing of the two FnIII domains that are locked in place by an interdomain ionic clasp required for binding. Disruption of BP230-β4 binding prevents recruitment of BP230 to Hemidesmosomes in human keratinocytes, revealing a key role of this interaction for Hemidesmosome assembly. Phosphomimetic substitutions in β4 and BP230 destabilize the complex. Thus, our study provides insights into the architecture of Hemidesmosomes and potential mechanisms of regulation.
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Structural basis of integrin {alpha}6{beta}4 interaction with the bullous pemphigoid antigen BP230 in Hemidesmosomes
bioRxiv, 2018Co-Authors: José A. Manso, Arnoud Sonnenberg, Maaike Kreft, María Teresa Gómez-hernández, Arturo Carabias, Noelia Alonso-garcía, Inés García-rubio, J.m. De PeredaAbstract:Mechanical stability of epithelia requires firm attachment of the cells to the basement membrane via complexes named Hemidesmosomes. Disorders that target hemidesmosomal proteins cause severe skin blistering diseases. In type I Hemidesmosomes, present in the epidermis, integrin 6{beta}4 is connected to intermediate filaments via plectin and BP230 (BPAG1e). To unravel the molecular basis of the BP230-{beta}4 interaction, we first mapped their mutual binding sites and subsequently solved the crystal structure of a human BP230-{beta}4 complex. BP230 binds to the fourth FnIII domain and in between the third and fourth FnIII domains of {beta}4, which in turn form an inter-domain ionic clasp required for binding. Using DEER, we show that BP230-binding induces closure of the two FnIII domains. Disruption of the BP230-{beta}4 interface prevents the recruitment of BP230 to Hemidesmosomes in keratinocytes in culture, revealing a key role of the BP230-{beta}4 interaction for the assembly of Hemidesmosomes. Phosphomimetic substitutions of T1663 of {beta}4, and T39 and S46 of BP230, disrupt binding, suggesting that the BP230-{beta}4 interaction might be regulated by phosphorylation during Hemidesmosome disassembly.
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The molecular architecture of Hemidesmosomes, as revealed with super-resolution microscopy.
Journal of Cell Science, 2015Co-Authors: Leila Nahidiazar, Arnoud Sonnenberg, Maaike Kreft, Bram Van Den Broek, Pablo Secades, Erik M. M. Manders, Kees JalinkAbstract:Hemidesmosomes have been extensively studied with immunofluorescence microscopy, but owing to its limited resolution, the precise organization of Hemidesmosomes remains poorly understood. We studied Hemidesmosome organization in cultured keratinocytes with two- and three-color super-resolution microscopy. We observed that, in the cell periphery, nascent Hemidesmosomes are associated with individual keratin filaments and that β4 integrin (also known as ITGB4) is distributed along, rather than under, keratin filaments. By applying innovative methods to quantify molecular distances, we demonstrate that the hemidesmosomal plaque protein plectin interacts simultaneously and asymmetrically with β4 integrin and keratin. Furthermore, we show that BP180 (BPAG2, also known as collagen XVII) and BP230 (BPAG1e, an epithelial splice variant of dystonin) are characteristically arranged within Hemidesmosomes with BP180 surrounding a central core of BP230 molecules. In skin cross-sections, Hemidesmosomes of variable sizes could be distinguished with BP230 and plectin occupying a position in between β4 integrin and BP180, and the intermediate filament system. In conclusion, our data provide a detailed view of the molecular architecture of Hemidesmosomes in cultured keratinocytes and skin.
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Current insights into the formation and breakdown of Hemidesmosomes
Trends in Cell Biology, 2006Co-Authors: Sandy H.m. Litjens, José M. De Pereda, Arnoud SonnenbergAbstract:Hemidesmosomes are multiprotein adhesion complexes that promote epithelial stromal attachment in stratified and complex epithelia. Modulation of their function is of crucial importance in a variety of biological processes, such as differentiation and migration of keratinocytes during wound healing and carcinoma invasion, in which cells become detached from the substrate and acquire a motile phenotype. Although much is known about the signaling potential of the α6β4 integrin in carcinoma cells, the events that coordinate the disassembly of Hemidesmosomes during differentiation and wound healing remain unclear. The binding of α6β4 to plectin has a central role in Hemidesmosome assembly and it is becoming clear that disrupting this interaction is a crucial event in Hemidesmosome disassembly. In addition, further insight into the functional interplay between α3β1 and α6β4 has contributed to our understanding of Hemidesmosome disassembly and cell migration.
Shashi Kumar Suman - One of the best experts on this subject based on the ideXlab platform.
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the plakin domain of c elegans vab 10 plectin acts as a hub in a mechanotransduction pathway to promote morphogenesis
bioRxiv, 2019Co-Authors: Shashi Kumar Suman, Csaba Daday, Teresa Ferraro, Thanh Thi Kim Vuongbrender, Sophie Quintin, Francois Robin, Frauke GraterAbstract:Mechanical forces control many cellular processes by eliciting a mechanotransduction response in target cells. The initial steps of mechanotransduction at Hemidesmosomes remain undefined in contrast to focal adhesions and adherens junctions. Here, we focus on the C. elegans plectin homolog VAB-10A, the only evolutionary conserved Hemidesmosome component. In C. elegans, muscle contractions induce a mechanotransduction pathway in the epidermis through Hemidesmosomes. We used CRISPR to precisely remove spectrin repeats (SR) or a partially hidden Src-homology-3 (SH3) domain within the VAB-10 plakin domain. Deleting the SH3 or SR8 domains in combination with mutations affecting mechanotransduction, or just part of SR5 shielding the SH3 domain induced embryonic elongation arrest because Hemidesmosomes collapse. Notably, recruitment of GIT-1, the first mechanotransduction player, requires the SR5 domain and the Hemidesmosome transmembrane receptor LET-805. Furthermore, Molecular Dynamics simulations confirmed that forces acting on VAB-10 can render the central SH3 domain, otherwise in contact with SR4, available for interaction. Collectively, our data strongly argue that the plakin domain plays a central role in mechanotransduction and raise the possibility that VAB-10/plectin might act as a mechanosensor.
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the plakin domain of c elegans vab 10 plectin acts as a hub in a mechanotransduction pathway to promote morphogenesis
Development, 2019Co-Authors: Shashi Kumar Suman, Csaba Daday, Teresa Ferraro, Thanh Thi Kim Vuongbrender, Sophie Quintin, Francois Robin, Frauke GraterAbstract:Mechanical forces can elicit a mechanotransduction response through junction-associated proteins. In contrast to the wealth of knowledge available for focal adhesions and adherens junctions, much less is known about mechanotransduction at Hemidesmosomes. Here, we focus on the C. elegans plectin homolog VAB-10A, the only evolutionary conserved Hemidesmosome component. In C. elegans, muscle contractions induce a mechanotransduction pathway in the epidermis through Hemidesmosomes. We used CRISPR to precisely remove spectrin repeats (SRs) or a partially hidden Src homology 3 (SH3) domain within the VAB-10 plakin domain. Deleting the SH3 or SR8 domains in combination with mutations affecting mechanotransduction, or just the part of SR5 shielding the SH3 domain, induced embryonic elongation arrest because Hemidesmosomes collapse. Notably, recruitment of GIT-1, the first mechanotransduction player, requires the SR5 domain and the Hemidesmosome transmembrane receptor LET-805. Furthermore, molecular dynamics simulations confirmed that forces acting on VAB-10 could make the central SH3 domain, otherwise in contact with SR4, available for interaction. Collectively, our data strongly indicate that the plakin domain plays a central role in mechanotransduction and raise the possibility that VAB-10/plectin might act as a mechanosensor.