Expression of intermediate filament-associated proteins paranemin and synemin in chicken development.

The expression of two intermediate filament-associated proteins, paranemin (280,000 mol wt) and synemin (230,000 mol wt), was investigated with respect to the expression of two core intermediate filament proteins, desmin and vimentin, in various embryonic and adult chicken muscle and nonmuscle cells. All developing muscle cells, regardless of their type, simultaneously express desmin, vimentin, paranemin, and synemin. However, a difference is observed in the expression of paranemin in adult muscle. This protein is removed during differentiation of both fast and slow skeletal muscle, visceral smooth muscle, and the smooth muscle of muscular arteries, but remains in mature myocardial cells, cardiac conducting fibers, and the smooth muscle cells of elastic arteries. Some of these cells express vimentin, others desmin, and still others a mixture of the two. On the other hand, synemin is expressed in all the above types of adult muscle cells except myocardial cells. Adult myocardial cells also lack vimentin, and its presence is gradually reduced after hatching. Since in adult striated muscle all expressed intermediate filament proteins are found predominantly in association with the peripheries of myofibrillar Z discs, these results suggest that a change in the composition of skeletal and cardiac muscle Z discs occurs during chicken development and maturation. Erythrocytes that express synemin and vimentin do not express paranemin, while both embryonic and adult Schwann cells co-express paranemin and vimentin, but not synemin. Endothelial cells of muscular vessels express paranemin, while those of elastic vessels do not, and neither contains synemin. Paranemin and synemin are not expressed in neurons, epithelial, and most glial cells, suggesting that these two polypeptides are expressed only in conjunction with desmin or vimentin. These results suggest that the composition of intermediate filaments changes during chicken development, not only with respect to their core subunit proteins but also with respect to two associated polypeptides, particularly in muscle cells.

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Regulation of slow calcium channels of myocardial cells and vascular smooth muscle cells by cyclic nucleotides and phosphorylation

Molecular and Cellular Biochemistry ◽

10.1007/bf00926749 ◽

1994 ◽

Vol 140 (2) ◽

pp. 103-117 ◽

Cited By ~ 45

Author(s):

Nicholas Sperelakis ◽

Zhiling Xiong ◽

G. Haddad ◽

Hiroshi Masuda

Keyword(s):

Smooth Muscle ◽

Calcium Channels ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Cyclic Nucleotides ◽

Muscle Cells ◽

Myocardial Cells

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Aquaporin-1 Expression in Visceral Smooth Muscle Cells of Female Rat Reproductive Tract

Journal of Smooth Muscle Research ◽

10.1540/jsmr.36.155 ◽

2000 ◽

Vol 36 (5) ◽

pp. 155-167 ◽

Cited By ~ 40

Author(s):

B.J. GANNON ◽

G.M. WARNES ◽

C.J. CARATI ◽

C.J. VERCO

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Reproductive Tract ◽

Muscle Cells ◽

Female Rat ◽

Aquaporin 1 ◽

Visceral Smooth Muscle

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Paranemin and the organization of desmin filament networks

Journal of Cell Science ◽

10.1242/jcs.114.6.1079 ◽

2001 ◽

Vol 114 (6) ◽

pp. 1079-1089 ◽

Cited By ~ 1

Author(s):

S.C. Schweitzer ◽

M.W. Klymkowsky ◽

R.M. Bellin ◽

R.M. Robson ◽

Y. Capetanaki ◽

...

Keyword(s):

Cell Lines ◽

Intermediate Filament ◽

Transgene Expression ◽

De Novo ◽

Muscle Cells ◽

The Other ◽

Intermediate Filament Proteins ◽

Mouse Fibroblasts ◽

Filament Networks ◽

Filament Network

De novo expression of vimentin, GFAP or peripherin leads to the assembly of an extended intermediate filament network in intermediate filament-free SW13/cl.2 cells. Desmin, in contrast, does not form extended filament networks in either SW13/cl.2 or intermediate filament-free mouse fibroblasts. Rather, desmin formed short thickened filamentous structures and prominent spot-like cytoplasmic aggregates that were composed of densely packed 9–11 nm diameter filaments. Analysis of stably transfected cell lines indicates that the inability of desmin to form extended networks is not due to a difference in the level of transgene expression. Nestin, paranemin and synemin are large intermediate filament proteins that coassemble with desmin in muscle cells. Although each of these large intermediate filament proteins colocalized with desmin when coexpressed in SW-13 cells, expression of paranemin, but not synemin or nestin, led to the formation of an extended desmin network. A similar rescue of desmin network organization was observed when desmin was coexpressed with vimentin, which coassembles with desmin, or with keratins, which formed a distinct filament network. These studies demonstrate that desmin filaments differ in their organizational properties from the other vimentin-like intermediate filament proteins and appear to depend upon coassembly with paranemin, at least when they are expressed in non-muscle cells, in order to form an extended filament network.

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Visceral Myopathy: Clinical syndromes, genetics, pathophysiology, and Fall of the Cytoskeleton

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00066.2021 ◽

2021 ◽

Author(s):

Sohaib Khalid Hashmi ◽

Rachel Helen Ceron ◽

Robert O Heuckeroth

Keyword(s):

Smooth Muscle ◽

Tissue Level ◽

Cytoskeletal Proteins ◽

Bladder Emptying ◽

Visceral Myopathy ◽

Crucial Component ◽

Associated Proteins ◽

Intestinal Pseudo Obstruction ◽

Visceral Smooth Muscle ◽

Contraction And Relaxation

Visceral smooth muscle is a crucial component of the walls of hollow organs like the gut, bladder, and uterus. This specialized smooth muscle has unique properties that distinguish it from other muscle types and that facilitate robust dilation and contraction. Visceral myopathies are diseases where severe visceral smooth muscle dysfunction prevents efficient movement of air and nutrients though the bowel, impairs bladder emptying, and affects normal uterine contraction and relaxation, particularly during pregnancy. Disease severity exists along a spectrum. The most debilitating defects cause highly dysfunctional bowel, reduced intrauterine colon growth (microcolon), and bladder emptying defects requiring catheterization, a condition called Megacystis Microcolon Intestinal Hypoperistalsis Syndrome (MMIHS). People with MMIHS often die early in childhood. When the bowel is the main organ affected and microcolon is absent, the condition is known as myopathic chronic intestinal pseudo-obstruction (CIPO). Visceral myopathies like MMIHS and myopathic CIPO are most commonly caused by mutations in contractile apparatus cytoskeletal proteins. Here, we review visceral myopathy-causing mutations and normal functions of these disease-associated proteins. We propose molecular, cellular, and tissue-level models that may explain clinical and histopathological features of visceral myopathy and hope these observations prompt new mechanistic studies.

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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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P-C1-31 Na+-Ca+2 exchange in the visceral smooth muscle cells

Progress in Biophysics and Molecular Biology ◽

10.1016/s0079-6107(97)80321-5 ◽

1996 ◽

Vol 65 ◽

pp. 94

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Visceral Smooth Muscle

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Analysis of cyclic AMP‐coupled signature molecules in human micro vascular smooth muscle cells shows link to stress‐associated proteins

The FASEB Journal ◽

10.1096/fasebj.24.1_supplement.870.1 ◽

2010 ◽

Vol 24 (S1) ◽

Author(s):

Selvi C Jeyaraj ◽

Nicholas T Unger ◽

N. Paul El‐Dahdah ◽

Richard J Sessler ◽

Matthew Zirwas ◽

...

Keyword(s):

Smooth Muscle ◽

Cyclic Amp ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Associated Proteins

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Identification of the intermediate filament protein synemin/SYNM as a target of myocardin family coactivators

AJP Cell Physiology ◽

10.1152/ajpcell.00047.2019 ◽

2019 ◽

Vol 317 (6) ◽

pp. C1128-C1142 ◽

Cited By ~ 4

Author(s):

Karl Swärd ◽

Katarzyna K. Krawczyk ◽

Björn Morén ◽

Baoyi Zhu ◽

Ljubica Matic ◽

...

Keyword(s):

Smooth Muscle ◽

Intermediate Filament ◽

Protein Level ◽

Time Course ◽

Target Genes ◽

Serum Response Factor ◽

Proximal Promoter ◽

Intermediate Filament Protein ◽

Intermediate Filament Proteins ◽

Filament Protein

Myocardin (MYOCD) is a critical regulator of smooth muscle cell (SMC) differentiation, but its transcriptional targets remain to be exhaustively characterized, especially at the protein level. Here we leveraged human RNA and protein expression data to identify novel potential MYOCD targets. Using correlation analyses we found several targets that we could confirm at the protein level, including SORBS1, SLMAP, SYNM, and MCAM. We focused on SYNM, which encodes the intermediate filament protein synemin. SYNM rivalled smooth muscle myosin ( MYH11) for SMC specificity and was controlled at the mRNA and protein levels by all myocardin-related transcription factors (MRTFs: MYOCD, MRTF-A/MKL1, and MRTF-B/MKL2). MRTF activity is regulated by the ratio of filamentous to globular actin, and SYNM was accordingly reduced by interventions that depolymerize actin, such as latrunculin treatment and overexpression of constitutively active cofilin. Many MRTF target genes depend on serum response factor (SRF), but SYNM lacked SRF-binding motifs in its proximal promoter, which was not directly regulated by MYOCD. Furthermore, SYNM resisted SRF silencing, yet the time course of induction closely paralleled that of the SRF-dependent target gene ACTA2. SYNM was repressed by the ternary complex factor (TCF) FLI1 and was increased in mouse embryonic fibroblasts lacking three classical TCFs (ELK1, ELK3, and ELK4). Imaging showed colocalization of SYNM with the intermediate filament proteins desmin and vimentin, and MRTF-A/MKL1 increased SYNM-containing intermediate filaments in SMCs. These studies identify SYNM as a novel SRF-independent target of myocardin that is abundantly expressed in all SMCs.

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