A common polymorphism (R577X) in the ACTN3 gene results in complete deficiency of -actinin-3 protein in 16% of humans worldwide. The presence of -actinin-3 protein is associated with improved sprint/power performance in athletes and the general population. Despite this, there is evidence that the null genotype XX has been acted on by recent positive selection, likely due to its emerging role in...

Nebulin is a high molecular weight polypeptide (mass 0.6-0.8 million) which accounts for 3% of the myofibrillar mass in skeletal muscle. Due to its resistance to extraction under native conditions, relatively little is known about the biochemistry of the molecule. Here we report in vitro binding of alpha-actinin (a major Z-line protein) to nebulin. After solubilization with sodium dodecylsulfat...

We have examined the possibility that epidermal growth factor (EGF)-induced morphological changes in human epidermoid carcinoma (A-431) cells are related to a reorganization of specific cytoskeletal elements affected by the hormone. It was found that EGF induced striking changes in the distribution of actin and a-actinin within these cells. After 30-45 min of exposure to EGF there was a marked ...

In HER2 (ErbB2)-overexpressing cells, transforming growth factor B (TGF-B), 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 survival. ...

A clone coding for the F-actin cross-linking protein ct-actinin was obtained by screening a genomic library of Dictyostelium discoideum DNA in ~,gtll with monoclonal antibodies specific for Dictyostelium ¢t-actinin. The 1.2-kilobase (kb) genomic clone was confirmed as containing part of the ¢t-actinin gene by comparing its nudeotide sequencev cith the amino acid sequence of tryptic peptides fro...

In this paper, a new type of spot desmosome-like junction (type II plaque) is described that is scattered along the entire lateral plasma membrane of rat and human intestinal epithelium. Ultrastructurally type II plaques differed from the classical type of epithelial spot desmosome ("macula adherens", further denoted as type I desmosome) by weak electron density of the membrane-associated plaqu...

Cultured cardiac myocytes were stained with antibodies to sarcomeric alpha-actinin, troponin-I, alpha-actin, myosin heavy chain (MHC), titin, myomesin, C-protein, and vinculin. Attention was focused on the distribution of these proteins with respect to nonstriated myofibrils (NSMFs) and striated myofibrils (SMFs). In NSMFs, alpha-actinin is found as longitudinally aligned, irregular approximate...

To investigate the mechanisms by which adhesions form and disperse in migrating cells, we expressed alpha 5 integrin, alpha-actinin, and paxillin as green fluorescent protein (GFP) fusions. All localized with their endogenous counterparts and did not perturb migration when expressed at moderate levels. alpha 5-GFP also rescued the adhesive defects in CHO B2 cells, which are alpha 5 integrin def...

The goal of the research was to identify the structural and functional characteristics of the rat's left ventricle under antiorthostatic suspension within 1, 3, 7 and 14 days, and subsequent 3 and 7-day reloading after a 14-day suspension. The transversal stiffness of the cardiomyocyte has been determined by the atomic force microscopy, cell respiration--by polarography and proteins content--by...