The endoplasmic reticulum (ER) transmembrane proteins, ATF6alpha and ATF6beta, are cleaved in response to ER stress, which can be induced by tunicamycin. The resulting N-terminal fragments of both ATF6 isoforms, which have conserved basic …
Overexpression studies have shown that the small heat shock proteins (sHSP) protect the myocardium from ischemia-reperfusion (I/R)-induced damage. However, gene deletion studies are necessary to demonstrate whether sHSPs are required for protection. …
OBJECTIVE: Our goal was to determine if the MKK6-p38 MAPK pathway regulates cardiac intracellular calcium ([Ca(2+)](i)). We also tested if MKK6 might influence expression of SERCA2, a calcium regulatory molecule involved in relaxation, and the …
Generation of proapoptotic sphingolipids by neutral sphingomyelinase activation is an early response to hypoxia/reoxygenation (HR) in cardiomyocytes. Factor associated with neutral sphingomyelinase activation (FAN) mediates activation of …
Cyclooxygenase-2 (COX-2) catalyzes the rate-limiting step in delayed prostaglandin biosynthesis. The purpose of this study was to evaluate the role of the MAP kinase kinase 6 (MKK6)-p38 MAPK signaling cascade in the regulation of myocardial COX-2 …
Calcium channels are important in a variety of cellular events including muscle contraction, signaling, proliferation, and apoptosis. Sphingolipids have been recognized as mediators of intracellular calcium release through their actions on a calcium …
AlphaB-crystallin (alphaBC), a small heat shock protein expressed in high levels in the heart, is phosphorylated on Ser-19, 45, and 59 after stress. However, it is not known whether alphaBC phosphorylation directly affects cell survival. In the …
ATF6 is a 670-amino acid endoplasmic reticulum (ER) transmembrane protein that is cleaved in response to ER stress. The resulting N-terminal fragment of approximately 400 amino acids translocates to the nucleus and activates selected ER …
Expression of constitutively active Ras (V12Ras) in cultured neonatal rat ventricular myocytes or targeted cardiac expression of V12Ras in transgenic mice induces myocardial cell growth and expression of genes that are markers of cardiac hypertrophy …
The recently described transcription factor, ATF6, mediates the expression of proteins that compensate for potentially stressful changes in the endoplasmic reticulum (ER), such as reduced ER calcium. In cardiac myocytes the maintenance of optimal …