Myocyte remodeling in response to hypertrophic stimuli requires nucleocytoplasmic shuttling of muscle LIM protein

Effects of deletion of muscle LIM protein on myocyte function.

Muscle LIM protein (MLP) may serve as a scaffold protein on the actin-based cytoskeleton, and mice deficient in this protein (MLPKO) have been recently reported to develop dilated cardiomyopathy. To determine the causes of depressed contractility in this model, we measured intracellular Ca2+ concentration ([Ca2+]i) transients (fluo 3), cell shortening, L-type Ca2+ channel current (I(Ca,L)), Na/...

Nucleocytoplasmic Shuttling of Endocytic Proteins

Many cellular processes rely on the ordered assembly of macromolecular structures. Here, we uncover an unexpected link between two such processes, endocytosis and transcription. Many endocytic proteins, including eps15, epsin1, the clathrin assembly lymphoid myeloid leukemia (CALM), and alpha-adaptin, accumulate in the nucleus when nuclear export is inhibited. Endocytosis and nucleocytoplasmic ...

Remodeling of myocyte dimensions in hypertrophic and atrophic rat hearts.

Changes in hemodynamic load cause alterations in cardiac myocyte size, with regional variations in myocyte size distribution possible within the ventricular wall. We studied regional changes in cellular dimensions and their distribution in two models of cardiac hypertrophy and in cardiac atrophy in the rat. Combined volume-pressure overload was produced by 3,3',5-triiodo-L-thyronine (T3) treatm...

The POU protein Oct-6 is a nucleocytoplasmic shuttling protein

Like many POU domain proteins, Oct-6 plays important roles during vertebrate development. In accord with its function as a transcriptional regulator during neurogenesis and myelination, Oct-6 is predominantly found in the nucleus. Nuclear import is mediated by a nuclear localization signal at the N-terminal end of the POU homeodomain. Here we show, that Oct-6 in addition contains a nuclear expo...

Nucleocytoplasmic Shuttling of HMGB1 Is