Change search
ReferencesLink to record
Permanent link

Direct link
Differences in the distribution of synemin, paranemin, and plectin in skeletal muscles of wild-type and desmin knock-out mice
Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Anatomy.
Université Paris.
Université Paris.
Baylor College of Medicine.
Show others and affiliations
2000 (English)In: Histochemistry and Cell Biology, ISSN 0948-6143, E-ISSN 1432-119X, Vol. 114, no 1, 39-47 p.Article in journal (Refereed) Published
Abstract [en]

Mice lacking the gene encoding for the intermediate filament protein desmin have a surprisingly normal myofibrillar organization in skeletal muscle fibers, although myopathy develops in highly used muscles. In the present study we examined how synemin, paranemin, and plectin, three key cytoskeletal proteins related to desmin, are organized in normal and desmin knock-out (K/O) mice. We show that in wild-type mice, synemin, paranemin, and plectin were colocalized with desmin in Z-disc-associated striations and at the sarcolemma. All three proteins were also present at the myotendinous junctions and in the postsynaptic area of motor endplates. In the desmin K/O mice the distribution of plectin was unaffected, whereas synemin and paranemin were partly affected. The Z-disc-associated striations were in general no longer present in between the myofibrils. In contrast, at the myotendinous and neuromuscular junctions synemin and paranemin were still present. Our study shows that plectin differs from synemin and paranemin in its binding properties to the myofibrillar Z-discs and that the cytoskeleton in junctional areas is particularly complex in its organization.

Place, publisher, year, edition, pages
Springer, 2000. Vol. 114, no 1, 39-47 p.
Keyword [en]
Cytoskeleton, Desmin knock-out mice, Intermediate filament-associated proteins, Myotendinous junctions, Neuromuscular junctions
National Category
Other Basic Medicine Cell and Molecular Biology
URN: urn:nbn:se:umu:diva-81914PubMedID: 10959821OAI: diva2:658817
Available from: 2013-10-23 Created: 2013-10-23 Last updated: 2014-03-26Bibliographically approved
In thesis
1. The muscle cytoskeleton of mice and men: Structural remodelling in desmin myopathies
Open this publication in new window or tab >>The muscle cytoskeleton of mice and men: Structural remodelling in desmin myopathies
2001 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The muscle fibre cytoskeleton of skeletal and heart muscle cells is composed mainly of intermediate filaments (IFs), that surround the myofibrils and connect the peripheral myofibrils with the sarcolemma and the nuclear membrane. Desmin is the first muscle specific IF protein to be produced in developing muscles and is the main IF protein in mature muscles. In skeletal muscle, desmin is particularly abundant at myotendinous and neuromuscular junctions. In the heart an increased amount of desmin is found at intercalated discs and in Purkinje fibres of the conduction system. Interactions between the IFs themselves, and between IFs and other structures such as Z-discs and the sarcolemma, are mediated by intermediate filament associated proteins (IFAPs). A transgenic mice model, which lacks the desmin gene have been developed to study the function of desmin. In these mice, morphological abnormalities are observed in both heart and skeletal muscles. Similar defects have been observed in human myopathies, caused by different mutations in the desmin gene. In the present thesis, skeletal and heart muscles of both wild type and desmin knock-out (K/O) mice have been investigated. Furthermore the cytoskeletal organisation in skeletal muscles from human controls and from a patient with desmin myopathy was examined.

In the desmin K/O mice, no morphological alterations were observed during embryogenesis. These mice postnatally developed a cardiomyopathy and a muscle dystrophy in highly used skeletal muscles. Ruptures of the sarcolemma appear to be the primary event leading to muscle degeneration and fibrosis both in cardiac and affected skeletal muscles. In the heart the muscle degeneration gave rise to calcifications, whereas in skeletal muscles regeneration of affected muscle was seen.

In mature wild type mice, the IF proteins synemin and paranemin, and the IFAP plectin were present together with desmin at the myofibrillar Z-discs, the sarcolemma, the neuromuscular junctions and the myotendinous junctions. Nestin was only found in these junctional regions. In desmin K/O mice, all four proteins were detected at neuromuscular and myotendinous junctions. The normal network of synemin and paranemin were not observed, whereas the distribution of plectin was preserved.

In normal human muscles, synemin, paranemin, plectin and αB-crystallin were colocalised with desmin in between the myofibrils, at the sarcolemma and at myotendinous and neuromuscular junctions. In the human desmin myopathy, the distribution of desmin varied considerably. A normal pattern was seen in some fibres areas, whereas other regions either contained large subsarcolemmal and intermyofibrillar accumulations of desmin or totally lacked desmin. Nestin, synemin, paranemin, plectin and αB-crystallin also exhibited an abnormal distribution. They were often aggregated in the areas that contained accumulations of desmin.

In cultured satellite cells from the patient, a normal network of desmin was present in early passages, whereas aggragates of desmin occurred upon further culturing. In the latter, also the nestin network was disrupted, whereas vimentin showed a normal pattern. αB-crystallin was only present in cells with a disrupted desmin network. Plectin was present in a subset of cells, irrespective of whether desmin was aggregated or showed a normal network.

From the present study it can be concluded that an intact desmin network is needed to maintain the integrity of muscle fibres. Desmin may be an important component in the assembly of proteins, which connect the extrasarcomeric cytoskeleton with the extracellular matrix.

Place, publisher, year, edition, pages
Umeå: Umeå universitet, 2001. 45 p.
Umeå University medical dissertations, ISSN 0346-6612 ; 754
desmin, nestin, synemin, paranemin, plectin, αB-crystallin, skeletal muscle, heart muscle, myotendinous junction, motor endplate, costamere
National Category
Basic Medicine
Research subject
Human Anatomy
urn:nbn:se:umu:diva-83451 (URN)91-7305-122-5 (ISBN)
Public defence
2001-11-01, Stora föreläsningssalen, biologihuset, Umeå universitet, Umeå, 09:00 (Swedish)
Available from: 2014-03-26 Created: 2013-11-26 Last updated: 2014-03-26Bibliographically approved

Open Access in DiVA

No full text


Search in DiVA

By author/editor
Carlsson, LenaThornell, Lars-Eric
By organisation
In the same journal
Histochemistry and Cell Biology
Other Basic MedicineCell and Molecular Biology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 45 hits
ReferencesLink to record
Permanent link

Direct link