Polarized total internal reflection fluorescence microscopy (polTIRFM) can be used to detect the spatial orientation and rotational dynamics of single molecules. polTIRFM determines the three-dimensional angular orientation and the extent of wobble of a fluorescent probe bound to the macromolecule of interest. This protocol describes how to label chicken calmodulin (CaM) with bifunctional rhoda...

The activity of calmodulin (CaM) is modulated not only by oscillations in the cytosolic concentration of free Ca(2+), but also by its phosphorylation status. In the present study, the role of tyrosine-phosphorylated CaM [P-(Tyr)-CaM] on the regulation of the epidermal growth factor receptor (EGFR) has been examined using in vitro assay systems. We show that phosphorylation of CaM by rat liver s...

Fibroblast growth factor-2 (FGF2) and vascular endothelial growth factor (VEGF) exert their angiogenic activity by interacting with endothelial cells in a distinct manner. In this study, we investigated the morphological features of endothelial cells of the chick embryo chorioallantoic membrane (CAM) microvasculature after stimulation with FGF2 or VEGF. In order to provide a continuous delivery...

To determine whether densities of calmodulin (CaM) and CaM-binding proteins are related to phasic and tonic behavior of smooth muscles, we quantified these proteins in the opossum esophageal body (EB) and lower esophageal sphincter (LES), which represent phasic and tonic smooth muscles, respectively. Gel electrophoresis, immunoprecipitation, Western blot, and hemagglutinin epitope-tagged CaM (H...

Background: Nanotechnology symbolizes a broad discipline with enormous potential in cancer treatment bridging one of the bottlenecks traditional approaches therapy which is an inability to deliver adequate quantities anti-cancer drugs tumor area. Studies on nanoparticles indicate their importance angiogenesis and metastasis. Aim: The present study assessed anti-angiogenesis anti-metastatic effe...

The HET-CAM (Hen's Egg Test-Chorioallantoic Membrane) assay is an in vitro alternative to the in vivo Draize Rabbit Eye test that mimics vascular changes in the chorioallantoic membrane. This qualitative method assesses the irritancy potential of chemicals. The CAM responds to injury with an inflammatory process similar to that in the rabbit eye's conjunctival tissue. Regarding topical toxicity...

Background: Bioactive compounds such as terpenoids, chondroitin sulfate, and polysaccharides with added value can be found in prestine marine creatures. These compounds often do have highly valuable therapeutic applications such as being antioxidant, antitumorogenic, anti-infl ammatory and anti-angiogenic. For the latter, varieties of angiogenesis factors can suppress this issu...

BACKGROUND Human endothelial nitric oxide synthase (eNOS) requires calcium-bound calmodulin (CaM) for electron transfer but the detailed mechanism remains unclear. METHODOLOGY/PRINCIPAL FINDINGS Using a series of CaM mutants with E to Q substitution at the four calcium-binding sites, we found that single mutation at any calcium-binding site (B1Q, B2Q, B3Q and B4Q) resulted in ∼2-3 fold increa...

Calmodulins (CaMs) are calcium-binding proteins playing vital roles in signal transduction regulating many aspects of plant development as well as responses to environmental stimuli by interacting with various classes of their binding partners including transcription factors (TFs). An increasing number of CaM-binding TFs have been identifi ed and characterized in Arabidopsis. However, a limited...

Protein-protein interactions are responsible for many biological processes, and the study of how proteins undergo a conformational change induced by other proteins in the immobilized state can help us to understand a protein's function and behavior, empower the current knowledge on molecular etiology of disease, as well as the discovery of putative protein targets of therapeutic interest. In th...