Background and Purpose—Niacin is the most effective medication in current clinical use for increasing high-density lipoprotein cholesterol. We tested the hypothesis that niacin treatment of stroke promotes synaptic plasticity and axon growth in the ischemic brain. Methods—Male Wistar rats were subjected to 2 hours of middle cerebral artery occlusion and treated with or without Niaspan (a prolon...

The interaction of myosin subfragment 1 (S1) with actin-tropomyosin-troponin (regulated actin) is highly nucleotide dependent. The binding of S1 or S1-ADP (but not S1-ATP nor N,N'-rho-phenylenedimaleimide-modified S1-ATP) to regulated actin activates ATP hydrolysis even in the absence of Ca(2+). Investigations with S1 and S1-ADP have led to the idea that some actin sites are directly blocked to...

A rapid method for the direct conjugation of affinity-purified antibodies with fluorescein (termed DCAPA) is described. This procedure involves the immobilization of antibodies as antigen-antibody complexes on nitrocellulose blots, and subsequently the bound antibodies are reacted with fluorescein isothiocyanate. An enriched sample of smooth muscle tropomysin transferred to nitrocellulose paper...

The dynamics of four regions of tropomyosin was assessed using saturation transfer electron paramagnetic resonance in the muscle fiber. In order to fully immobilize the spin probe on the surface of tropomyosin, a bi-functional spin label was attached to i,i+4 positions via cysteine mutagenesis. The dynamics of bi-functionally labeled tropomyosin mutants decreased by three orders of magnitude wh...

To study how contractile proteins become organized into sarcomeric units in striated muscle, we have exposed glycerinated myofibrils to fluorescently labeled actin, alpha-actinin, and tropomyosin. In this in vitro system, alpha-actinin bound to the Z-bands and the binding could not be saturated by prior addition of excess unlabeled alpha-actinin. Conditions known to prevent self-association of ...

BACKGROUND Seawater and freshwater shrimp are some of the most common causes of food allergy among children in Thailand. Tropomyosin has been reported as a major allergen for shrimp allergic populations around the world. Despite a high number of shrimp-allergic Thai children, however, it is unknown whether shrimp tropomyosin is a major cause of allergic reactions. OBJECTIVES To clone and char...

Myosin-binding protein C (MyBP-C) is an accessory protein of striated muscle thick filaments and a modulator of cardiac muscle contraction. Defects in the cardiac isoform, cMyBP-C, cause heart disease. cMyBP-C includes 11 Ig- and fibronectin-like domains and a cMyBP-C-specific motif. In vitro studies show that in addition to binding to the thick filament via its C-terminal region, cMyBP-C can a...

The human erythrocyte membrane skeleton consists of a network of short actin filaments cross-linked into a hexagonal network by long, flexible spectrin molecules. The lengths of the short actin filaments (33 +/- 5 nm) at the central junctions are proposed to be stabilized and limited by association with tropomyosin and the tropomyosin-binding protein, tropomodulin. Here, we use immunogold label...

Oxidative stress induces in endothelial cells a quick and transient coactivation of both stress-activated protein kinase-2/p38 and extracellular signal-regulated kinase (ERK) mitogen-activated protein kinases. We found that inhibiting the ERK pathway resulted, within 5 min of oxidative stress, in a misassembly of focal adhesions characterized by mislocalization of key proteins such as paxillin....

BACKGROUND Tropomyosin is a prototypical coiled coil along its length with subtle variations in structure that allow interactions with actin and other proteins. Actin binding globally stabilizes tropomyosin. Tropomyosin-actin interaction occurs periodically along the length of tropomyosin. However, it is not well understood how tropomyosin binds actin. PRINCIPAL FINDINGS Tropomyosin's periodi...