Abstract
We report the cloning and functional characterization of myopodin, the second member of the synaptopodin gene family. Myopodin shows no significant homology to any known protein except synaptopodin. Northern blot analysis resulted in a 3.6-kb transcript for mouse skeletal and heart muscle. Western blots showed an 80-kD signal for skeletal and a 95-kD signal for heart muscle. Myopodin contains one PPXY motif and multiple PXXP motifs. Myopodin colocalizes with alpha-actinin and is found at the Z-disc as shown by immunogold electron microscopy. In myoblasts, myopodin shows preferential nuclear localization. During myotube differentiation, myopodin binds to stress fibers in a punctuated pattern before incorporation into the Z-disc. Myopodin can directly bind to actin and contains a novel actin binding site in the center of the protein. Myopodin has actin-bundling activity as shown by formation of latrunculin-A-sensitive cytosolic actin bundles and nuclear actin loops in transfected cells expressing green fluorescent protein-myopodin. Under stress conditions, myopodin accumulates in the nucleus and is depleted from the cytoplasm. Nuclear export of myopodin is sensitive to leptomycin B, despite the absence of a classical nuclear export sequence. We propose a dual role for myopodin as a structural protein also participating in signaling pathways between the Z-disc and the nucleus.
| Original language | English |
|---|---|
| Pages (from-to) | 393-404 |
| Number of pages | 12 |
| Journal | The Journal of cell biology |
| Volume | 155 |
| Issue number | 3 |
| State | Published - Oct 29 2001 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Medicine(all)
Cite this
Differentiation- and stress-dependent nuclear cytoplasmic redistribution of myopodin, a novel actin-bundling protein. / Weins, Astrid; Schwarz, Karin; Faul, Christian H; Barisoni-Thomas, Laura; Linke, Wolfgang A.; Mundel, Peter.
In: The Journal of cell biology, Vol. 155, No. 3, 29.10.2001, p. 393-404.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Differentiation- and stress-dependent nuclear cytoplasmic redistribution of myopodin, a novel actin-bundling protein
AU - Weins, Astrid
AU - Schwarz, Karin
AU - Faul, Christian H
AU - Barisoni-Thomas, Laura
AU - Linke, Wolfgang A.
AU - Mundel, Peter
PY - 2001/10/29
Y1 - 2001/10/29
N2 - We report the cloning and functional characterization of myopodin, the second member of the synaptopodin gene family. Myopodin shows no significant homology to any known protein except synaptopodin. Northern blot analysis resulted in a 3.6-kb transcript for mouse skeletal and heart muscle. Western blots showed an 80-kD signal for skeletal and a 95-kD signal for heart muscle. Myopodin contains one PPXY motif and multiple PXXP motifs. Myopodin colocalizes with alpha-actinin and is found at the Z-disc as shown by immunogold electron microscopy. In myoblasts, myopodin shows preferential nuclear localization. During myotube differentiation, myopodin binds to stress fibers in a punctuated pattern before incorporation into the Z-disc. Myopodin can directly bind to actin and contains a novel actin binding site in the center of the protein. Myopodin has actin-bundling activity as shown by formation of latrunculin-A-sensitive cytosolic actin bundles and nuclear actin loops in transfected cells expressing green fluorescent protein-myopodin. Under stress conditions, myopodin accumulates in the nucleus and is depleted from the cytoplasm. Nuclear export of myopodin is sensitive to leptomycin B, despite the absence of a classical nuclear export sequence. We propose a dual role for myopodin as a structural protein also participating in signaling pathways between the Z-disc and the nucleus.
AB - We report the cloning and functional characterization of myopodin, the second member of the synaptopodin gene family. Myopodin shows no significant homology to any known protein except synaptopodin. Northern blot analysis resulted in a 3.6-kb transcript for mouse skeletal and heart muscle. Western blots showed an 80-kD signal for skeletal and a 95-kD signal for heart muscle. Myopodin contains one PPXY motif and multiple PXXP motifs. Myopodin colocalizes with alpha-actinin and is found at the Z-disc as shown by immunogold electron microscopy. In myoblasts, myopodin shows preferential nuclear localization. During myotube differentiation, myopodin binds to stress fibers in a punctuated pattern before incorporation into the Z-disc. Myopodin can directly bind to actin and contains a novel actin binding site in the center of the protein. Myopodin has actin-bundling activity as shown by formation of latrunculin-A-sensitive cytosolic actin bundles and nuclear actin loops in transfected cells expressing green fluorescent protein-myopodin. Under stress conditions, myopodin accumulates in the nucleus and is depleted from the cytoplasm. Nuclear export of myopodin is sensitive to leptomycin B, despite the absence of a classical nuclear export sequence. We propose a dual role for myopodin as a structural protein also participating in signaling pathways between the Z-disc and the nucleus.
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UR - http://www.scopus.com/inward/citedby.url?scp=84924091885&partnerID=8YFLogxK
M3 - Article
C2 - 11673475
AN - SCOPUS:0035851920
VL - 155
SP - 393
EP - 404
JO - Journal of Cell Biology
JF - Journal of Cell Biology
SN - 0021-9525
IS - 3
ER -