Desmoplakin interacts with the coil 1 of different types of intermediate filament proteins and displays high affinity for assembled intermediate filaments

We report here on the in vivo assembly of alpha-internexin, a type IV neuronal intermediate filament protein, in transfected cultured cells, comparing its assembly properties with those of the neurofilament triplet proteins (NF-L, NF-M, and NF-H). Like the neurofilament triplet proteins, alpha-internexin coassembles with vimentin into filaments. To study the assembly characteristics of these proteins in the absence of a preexisting filament network, transient transfection experiments were performed with a non-neuronal cell line lacking cytoplasmic intermediate filaments. The results showed that only alpha-internexin was able to self-assemble into extensive filamentous networks. In contrast, the neurofilament triplet proteins were incapable of homopolymeric assembly into filamentous arrays in vivo. NF-L coassembled with either NF-M or NF-H into filamentous structures in the transfected cells, but NF-M could not form filaments with NF-H. alpha-internexin could coassemble with each of the neurofilament triplet proteins in the transfected cells to form filaments. When all but 2 and 10 amino acid residues were removed from the tail domains of NF-L and NF-M, respectively, the resulting NF-L and NF-M deletion mutants retained the ability to coassemble with alpha-internexin into filamentous networks. These mutants were also capable of forming filaments with other wild-type neurofilament triplet protein subunits. These results suggest that the tail domains of NF-L and NF-M are dispensable for normal coassembly of each of these proteins with other type IV intermediate filament proteins to form filaments.

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Molecular analysis of intermediate filament cytoskeleton--a putative load-bearing structure

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1984.246.4.h566 ◽

1984 ◽

Vol 246 (4) ◽

pp. H566-H572 ◽

Cited By ~ 2

Author(s):

M. G. Price

Keyword(s):

Skeletal Muscle ◽

Molecular Analysis ◽

Intermediate Filaments ◽

Intermediate Filament ◽

Direct Evidence ◽

Two Dimensional ◽

Myocardial Cells ◽

Intermediate Filament Proteins ◽

Bovine Myocardium ◽

Bearing Structure

Myocardial cells contain a cytoskeleton of intermediate filaments connecting the myofibrils. The present molecular analysis of the myocardial cytoskeleton was designed to identify the intermediate filament proteins and examine their assembly properties. The intermediate filament proteins desmin and vimentin were isolated from adult bovine myocardium by sequential extraction, urea solubilization, and chromatography on hydroxylapatite and DEAE columns. Desmin was obtained virtually pure in one peak and in a mixture of desmin and vimentin in the trailing fractions. Intermediate filaments of different morphologies polymerized in the desmin and the desmin-vimentin fractions. Isolated myocardial desmin occurs as three isozymes and isolated myocardial vimentin as two isozymes, which co-migrate on two-dimensional gels with corresponding isozymes from bovine skeletal and smooth muscle. Polypeptides of 200,000 and 220,000 daltons that fractionate with myocardial desmin and vimentin are also present in cytoskeletons of smooth and skeletal muscle. The results provide direct evidence that myocardial desmin can assemble to form intermediate filaments, suggesting that desmin is the major component of the cytoskeletal filaments in cardiomyocytes.

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Differential effect of arginine modification with 1,2-cyclohexanedione on the capacity of vimentin and desmin to assemble into intermediate filaments and to bind to nucleic acids

Journal of Cell Science ◽

10.1242/jcs.65.1.1 ◽

1984 ◽

Vol 65 (1) ◽

pp. 1-20

Author(s):

P. Traub ◽

C.E. Vorgias

Keyword(s):

Nucleic Acids ◽

Intermediate Filaments ◽

Intermediate Filament ◽

Specific Interaction ◽

Inhibitory Effect ◽

Affinity Column ◽

Intermediate Filament Proteins ◽

Amino Terminal ◽

Short Period ◽

Arginine Residues

When the intermediate filament proteins vimentin and desmin were reacted for a short period of time with the arginine-specific reagent 1,2-cyclohexanedione, the modification had a severe, inhibitory effect on the assembly of intermediate filaments and on the susceptibility of the basic, amino-terminal polypeptide of both proteins to degradation by the intermediate filament-specific, Ca2+-activated proteinase. However, it had only a slightly inhibitory effect on the binding of vimentin and desmin to ribosomal RNA from Ehrlich ascites tumour cells. Since the Ca2+-activated proteinase is very likely to be a trypsin-like enzyme, with a preference for arginyl and lysyl peptide bonds, the results indicate that the arginine residues of the amino-terminal polypeptide of vimentin and desmin are highly essential for filament assembly but largely dispensable for the binding of both proteins to nucleic acids. This was supported by the observation that two breakdown products of vimentin lacking a 5 X 10(3) Mr and an 8 X 10(3) Mr polypeptide from the amino terminus, respectively, did not assemble into intermediate filaments but were still capable of binding to rRNA. Both polypeptides also bound to single-stranded DNA-cellulose under non-denaturing conditions, but passed the affinity column in the presence of 6 M-urea. Thus, the binding of vimentin to nucleic acids appears to be based on two components: a non-specific electrostatic interaction mediated by the positively charged arginine residues of the amino-terminal polypeptide that is insensitive to denaturation by urea, and a specific interaction that is sensitive to denaturation by urea.

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SUMOylation of periplakin is critical for efficient reorganization of keratin filament network

Molecular Biology of the Cell ◽

10.1091/mbc.e18-04-0244 ◽

2019 ◽

Vol 30 (3) ◽

pp. 357-369 ◽

Cited By ~ 5

Author(s):

Mansi Gujrati ◽

Rohit Mittal ◽

Lakhan Ekal ◽

Ram Kumar Mishra

Keyword(s):

Intermediate Filaments ◽

Okadaic Acid ◽

Intermediate Filament ◽

Time Lapse ◽

Intermediate Filament Proteins ◽

Enhanced Sensitivity ◽

Response To Stress ◽

Keratin Filament ◽

Time Lapse Imaging ◽

Linker Domain

The architecture of the cytoskeleton and its remodeling are tightly regulated by dynamic reorganization of keratin-rich intermediate filaments. Plakin family proteins associate with the network of intermediate filaments (IFs) and affect its reorganization during migration, differentiation, and response to stress. The smallest plakin, periplakin (PPL), interacts specifically with intermediate filament proteins K8, K18, and vimentin via its C-terminal linker domain. Here, we show that periplakin is SUMOylated at a conserved lysine in its linker domain (K1646) preferentially by small ubiquitin-like modifier 1 (SUMO1). Our data indicate that PPL SUMOylation is essential for the proper reorganization of the keratin IF network. Stresses perturbing intermediate-filament and cytoskeletal architecture induce hyper-SUMOylation of periplakin. Okadaic acid induced hyperphosphorylation-dependent collapse of the keratin IF network results in a similar hyper-SUMOylation of PPL. Strikingly, exogenous overexpression of a non-SUMOylatable periplakin mutant (K1646R) induced aberrant bundling and loose network interconnections of the keratin filaments. Time-lapse imaging of cells expressing the K1646R mutant showed the enhanced sensitivity of keratin filament collapse upon okadaic acid treatment. Our data identify an important regulatory role for periplakin SUMOylation in dynamic reorganization and stability of keratin IFs.

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Alterations of intermediate filaments in various histopathological conditions

Biochemistry and Cell Biology ◽

10.1139/o95-069 ◽

1995 ◽

Vol 73 (9-10) ◽

pp. 627-634 ◽

Cited By ~ 5

Author(s):

Monique Cadrin ◽

Maria-Grazia Martinoli

Keyword(s):

Intermediate Filaments ◽

Intermediate Filament ◽

Lewy Bodies ◽

Degenerative Diseases ◽

Intermediate Filament Proteins ◽

Mallory Bodies ◽

Filament Structure ◽

Cytoskeletal Component ◽

Filament Networks ◽

Precise Role

Intermediate filament proteins belong to a multigene family and constitute an important cytoskeletal component of most vertebrate cells. Their pattern of expression is tissue specific and is highly controlled during embryonic development. Numerous pathologies are known to be associated with modifications of intermediate filament organisation, although their precise role has not yet been elucidated. The present review focuses on the most recent data concerning the possible causes of intermediate filaments disorganization in specific pathologic conditions affecting the epidermis, the liver, and the nervous system. We discuss the formation of abnormal intermediate filament networks that arise as a consequence of mutations that directly affect intermediate filament structure or are induced by multifactorial causes such as modifications of post-translational processes and changes in the levels of expression.Key words: intermediate filaments, phosphorylation, Mallory bodies, Lewy bodies, degenerative diseases.

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Reactivity of monoclonal antibodies against intermediate filament proteins during embryonic development

Development ◽

10.1242/dev.64.1.45 ◽

1981 ◽

Vol 64 (1) ◽

pp. 45-60

Author(s):

Rolf Kemler ◽

Philippe Brûlet ◽

Marie-Thérèse Schnebelen ◽

Jean Gaillard ◽

François Jacob

Keyword(s):

Monoclonal Antibodies ◽

Epithelial Cells ◽

Embryonic Development ◽

Tissue Distribution ◽

Intermediate Filaments ◽

Intermediate Filament ◽

Adult Tissue ◽

Reactivity Pattern ◽

Germ Layers ◽

Intermediate Filament Proteins

Monoclonal antibodies (mAbs) against a preparation of intermediate filaments from trophoblastoma cells were studied for their reactivity pattern during embryonic development and on adult tissue cells. Up to day 12 of embryonic development, epithelial cells of the three germ layers reacted with these mAbs. Later during development and in adult tissues, positive reactions could be observed only with epithelial cells derived from mesoderm and endoderm. Because of their tissue distribution, the proteins reacting with these mAbs might belong to the keratin family of intermediate filaments or they might represent a new group of intermediate filaments.

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Immunological characterization of lamins in the nuclear matrix of onion cells

Journal of Cell Science ◽

10.1242/jcs.106.1.431 ◽

1993 ◽

Vol 106 (1) ◽

pp. 431-439 ◽

Cited By ~ 5

Author(s):

A. Minguez ◽

S. Moreno Diaz de la Espina

Keyword(s):

Intermediate Filaments ◽

Nuclear Matrix ◽

Intermediate Filament ◽

Higher Plants ◽

Nuclear Periphery ◽

Immunogold Labelling ◽

Root Cells ◽

Intermediate Filament Proteins ◽

Lamin B

We have used polyclonal and monoclonal antibodies against different lamins from vertebrates, and the IFA antibody recognizing all kinds of intermediate filament proteins, to investigate the lamins of the nuclear matrix of Allium cepa meristematic root cells. All the antibodies react in the onion nuclear matrix with bands in the range of 60–65 kDa, which are enriched in the nuclear matrix after urea extraction, and do not crossreact with other antibodies recognizing intermediate filaments in plants (AFB, anti-vimentin and MAC 322), ruling out crossreaction with contaminating intermediate filaments of cytoplasmic bundles. In 2-D blots the chicken anti-lamin serum reacts with one spot at 65 kDa and pI 6.8 and the anti B-type lamin antibodies with another one at 64 kDa and pI 5.75. Both crossreact with IFA. The lamin is localized at the nuclear periphery and the lamina by indirect immunofluorescence. Immunogold labelling of nuclear matrix sections reveals that the protein is not only associated with the lamina, but also with the internal matrix. Taken together these results reveal that higher plants, which do not possess an organized network of cytoplasmic intermediate filaments, nevertheless present a well-organized lamina containing lamins in which at least one of them is immunologically related to vertebrate lamin B. Our data confirm that lamins are very old members of the intermediate filament proteins that have been better conserved in plants during evolution than their cytoplasmic counterparts.

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Intermediate filament proteins: many unanswered questions, few unquestioned answers

Biochemistry and Cell Biology ◽

10.1139/o92-132 ◽

1992 ◽

Vol 70 (10-11) ◽

pp. 842-848 ◽

Cited By ~ 4

Author(s):

Micheline Paulin-Levasseur

Keyword(s):

Intermediate Filaments ◽

Nuclear Matrix ◽

Intermediate Filament ◽

Expression Patterns ◽

Supramolecular Assembly ◽

Cellular Mechanisms ◽

Specific Expression ◽

Intermediate Filament Proteins ◽

Nuclear Lamins ◽

New Concepts

Major constituents of the cytoskeleton and the nuclear matrix, cytoplasmic intermediate filament subunits and nuclear lamins belong to a multigene family of proteins whose function is poorly understood. It has now become a general contention that important clues to the physiological roles of these proteins may reside in their developmental and tissue-specific expression patterns, as well as their cellular organization. The present review brings into focus experimental strategies that have been developed, over the past few years, to gain insights into the cellular mechanisms regulating the molecular polymorphism and supramolecular assembly of intermediate filaments. In this context new concepts are discussed that may be pivotal for the orientation of future studies on intermediate filament proteins.Key words: intermediate filaments, nuclear lamins, cytoskeleton, nuclear matrix.

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Intermediate filaments EXC-2 and IFA-4 Maintain Luminal Structure of the Tubular Excretory Canals in Caenorhabditis elegans

10.1101/277111 ◽

2018 ◽

Author(s):

Hikmat I. Al-Hashimi ◽

David H. Hall ◽

Brian D. Ackley ◽

Erik A. Lundquist ◽

Matthew Buechner

Keyword(s):

Caenorhabditis Elegans ◽

Intermediate Filaments ◽

Intermediate Filament ◽

Light And Electron Microscopy ◽

Intermediate Filament Protein ◽

Apical Surface ◽

Intermediate Filament Proteins ◽

Canal Diameter ◽

Excretory Canals ◽

Filament Protein

ABSTRACTThe excretory canals of Caenorhabditis elegans are a model for understanding the maintenance of apical morphology in narrow single-celled tubes. Light and electron microscopy shows that mutants in exc-2 start to form canals normally, but these swell to develop large fluid-filled cysts that lack a complete terminal web at the apical surface, and accumulate filamentous material in the canal lumen. Here, whole-genome sequencing and gene rescue show that exc-2 encodes intermediate filament protein IFC-2. EXC-2/IFC-2 protein, fluorescently tagged via CRISPR/Cas9, is located at the apical surface of the canals independently of other intermediate filament proteins. EXC-2 is also located in several other tissues, though the tagged isoforms are not seen in the larger intestinal tube. Tagged EXC-2 binds via pulldown to intermediate filament protein IFA-4, which is also shown to line the canal apical surface. Overexpression of either protein results in narrow but shortened canals. These results are consistent with a model whereby three intermediate filaments in the canals, EXC-2, IFA-4, and IFB-1, restrain swelling of narrow tubules in concert with actin filaments that guide the extension and direction of tubule outgrowth, while allowing the tube to bend as the animal moves.Article SummaryThe C. elegans excretory canals form a useful model for understanding formation of narrow tubes. exc-2 mutants start to form normal canals that then swell into fluid-filled cysts. We show that exc-2 encodes a large intermediate filament (IF) protein previously not thought to be located in the canals. EXC-2 is located at the apical (luminal) membrane, binds to another IF protein, and appears to be one of three IF proteins that form a flexible meshwork to maintain the thin canal diameter. This work provides a genetically useful model for understanding the interactions of IF proteins with other cytoskeletal elements to regulate tube size and growth.

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