Angiotensin II (Ang II) plays an important role in cardiac remodeling through stimulation of proliferation and extracellular matrix (ECM) production in cardiac fibroblasts. Integrins are a family of transmembrane receptors that mediate the attachment of cells to ECM. We hypothesized that Ang II regulation of integrins further contributes to its role in cardiac remodeling. We cultured adult rat ...

Indirect immunofluorescence microscopy was used to localize microfilament-associated proteins in the brush border of mouse intestinal epithelial cells. As expected, antibodies to actin decorated the microfilaments of the microvilli, giving rise to a very intense fluorescence. By contrast, antibodies to myosin, tropomyosin, filamin, and alpha-actinin did not decorate the microvilli. All these an...

Proper positioning of the cleavage furrow is essential for successful cell division. The mitotic spindle, which consists of dynamic astral microtubules and stable equatorial microtubules is responsible for this process. However, little is known about how microtubules are regulated in a time- and region-dependent manner. Here, we show that α-actinin-regulated cortical actin filament integrity is...

In HER2 (ErbB2)-overexpressing cells, transforming growth factor beta (TGF-beta), via activation of phosphoinositide-3 kinase (PI3K), recruits actin and actinin to HER2, which then colocalizes with Vav2, activated Rac1, and Pak1 at cell protrusions. This results in prolonged Rac1 activation, enhanced motility and invasiveness, Bad phosphorylation, uncoupling of Bad/Bcl-2, and enhanced cell surv...

Chick heart development was studied using transmission electron microscopy and SDS-polyacrylamide gel electrophoresis in combination with densitometry. Myosin heavy chain, alpha-actinin, actin and tropomyosin accumulations were analysed in developing hearts from preheartbeat stage 9 (Hamburger-Hamilton staging series) through 2 days after hatching. At the preheartbeat stage, electron microscopy...

Reaction Symbol Value [for simulation] Reference Actin diffusion kactin, diff 20 μm 2 · s−1 [80 s−1] a α-actinin diffusion kα,diff kactin, diff/10 s −1 a NMIIA mini-filament diffusion kNMIIA, diff kactin, diff/100 s −1 a Actin polymerization at plus end kactin,poly,+ 11.6 μM −1s−1 [0.151 s−1] b [1] Actin polymerization at minus end kactin,poly,− 1.3 μM −1s−1 [0.017 s−1] b [1] Actin depolymeriza...

It was recently shown by combined immunofluorescence and interference reflection microscopy that a protein named vinculin, along with alpha-actinin, is concentrated at focal adhesion plaques inside cultured normal fibroblasts [Geiger, B. (1979) Cell 18, 193-205]. These plaques are the discrete, isolated sites of strong adhesions formed between the ventral surfaces of the cells and the substrata...

The ultrastructural localization of alpha-actinin and vinculin in chicken cardiac muscle was studied by double indirect immunoelectron microscopy, using ferritin and iron-dextran (Imposil) as the electron-dense markers conjugated to the secondary antibodies, on ultrathin frozen sections of fixed tissue. Fixation and immunolabeling procedures were developed that permitted maximal retention of th...