Large-scale chromatin decondensation has been observed after the targeting of certain acidic activators to heterochromatic chromatin domains. Acidic activators are often modular, with two or more separable transcriptional activation domains. Whether these smaller regions are sufficient for all functions of the activators has not been demonstrated. We adapted an inducible heterodimerization syst...

The rate of the ATP:glucose transphosphorylase reaction catalyzed by yeast hexokinase, isozyme PII, is inhibited by lowering the pH of the reaction below 7.0, especially at suboptimal concentrations of ATP. This effect of acidity is largely overcome by activators such as orthophosphate, citrate, malate, 3-phosphoglycerate, and riboside triphosphates. Thus, in the acid range, ATP appears to serv...

Calorie restriction (CR) is a non-genetic manipulation that reliably results in extended lifespan of several species ranging from yeast to dogs. The lifespan extension effect of CR has been strongly associated with an increased level and activation of the silent information regulator 2 (Sir2) histone deacetylase and its mammalian ortholog Sirt1. This association led to the search for potential ...