A transcription factor links growth rate and metabolism in the hypersaline adapted archaeon Halobacterium salinarum.

Co-ordinating metabolism and growth is a key challenge for all organisms. Despite fluctuating environments, cells must produce the same metabolic outputs to thrive. The mechanisms underlying this 'growth homeostasis' are known in bacteria and eukaryotes, but remain unexplored in archaea.

The RosR transcription factor is required for gene expression dynamics in response to extreme oxidative stress in a hypersaline-adapted archaeon.

Background: Previous work has shown that the hypersaline-adapted archaeon, Halobacterium salinarum NRC-1, is highly resistant to oxidative stress caused by exposure to hydrogen peroxide, UV, and gamma radiation. Dynamic alteration of the gene regulatory network (GRN) has been implicated in such resistance. However, the molecular functions of transcription regulatory proteins involved in this response remain unknown.

Effects of N-cadherin overexpression on the adhesion properties of embryonic stem cells.

Constitutive overexpression of N-cadherin in mouse embryonic stem cells led to marked changes in the phenotype and adhesion properties of these cells. The changes included the formation of smaller embryonic bodies, elevated mRNA and total protein levels of N-cadherin, and increased amounts of p120 catenin and connexin-43. N-cadherin cells exhibited decreased attachment to non-cell surfaces, while their adhesiveness to each other and to rat neonatal cardiomyocytes was significantly elevated.

Clinically relevant concentrations of di (2-ethylhexyl) phthalate (DEHP) uncouple cardiac syncytium.

Di(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer found in a variety of polyvinyl chloride (PVC) medical products. The results of studies in experimental animals suggest that DEHP leached from flexible PVC tubing may cause health problems in some patient populations. While the cancerogenic and reproductive effects of DEHP are well recognized, little is known about the potential adverse impact of phthalates on the heart.

Formation of cardiac fibers in Matrigel matrix.

We report a simple in vitro model of cardiac tissue that mimics three-dimensional (3-D) environment and mechanical load conditions and, as such, may serve as a convenient method to study stem cell engraftment or address developmental questions such as cytoskeleton or intercalated disk maturation. To create in vitro cardiac fibers we used Matrigel, a commercially available basement membrane preparation. A semisolid pillow from concentrated Matrigel was overlaid with a suspension of rat neonatal cardiomyocytes in a diluted Matrigel solution.