Thoracic aortic aneurysm (TAAD)-causing mutation in actin affects formin regulation of polymerization.

More than 30 mutations in ACTA2, which encodes α-smooth muscle actin, have been identified to cause autosomal dominant thoracic aortic aneurysm and dissection. The mutation R256H is of particular interest because it also causes patent ductus arteriosus and moyamoya disease. R256H is one of the more prevalent mutations and, based on its molecular location near the strand-strand interface in the actin filament, may affect F-actin stability.

Allele-specific effects of thoracic aortic aneurysm and dissection alpha-smooth muscle actin mutations on actin function.

Twenty-two missense mutations in ACTA2, which encodes α-smooth muscle actin, have been identified to cause thoracic aortic aneurysm and dissection. Limited access to diseased tissue, the presence of multiple unresolvable actin isoforms in the cell, and lack of an animal model have prevented analysis of the biochemical mechanisms underlying this pathology. We have utilized actin from the yeast Saccharomyces cerevisiae, 86% identical to human α-smooth muscle actin, as a model.

Echocardiographic assessment of cardiac morphology and function in Xenopus.

Advances using Xenopus as a model permit valuable inquiries into cardiac development from embryo to adult. Noninvasive methods are needed to study cardiac function longitudinally. The objective of this study was to evaluate the feasibility of echocardiographic studies in Xenopus and establish normative data of adult cardiac structure and function.

Cardiomyopathy in offspring of diabetic rats is associated with activation of the MAPK and apoptotic pathways.

Background: Maternal diabetes affects the developing fetal cardiovascular system. Newborn offspring of diabetic mothers can have a transient cardiomyopathy. We hypothesized that cardiomyopathic remodeling is associated with activation of the mitogen activated protein kinase (MAPK) signaling and apoptotic pathways.