The Bcl6-SMRT/NCoR cistrome represses inflammation to attenuate atherosclerosis

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Highlights? Bcl6 is a critical antiatherogenic regulator ? Inhibition of Bcl6-SMRT/NCoR interactions induces atherogenic gene expression ? SMRT and NCoR cistromes each exceed 30,000 sites, with a nearly 50% overlap ? Bcl6 recruits SMRT and NCoR to NF-κB-driven inflammatory and tissue remodeling genes     

Hair type,intake, and detection method influence Rhodamine B detectability

Rhodamine B (RB) is a popular bait-marking tool in wildlife research, although its use has required many assumptions about marking reliability. These assumptions have limited dosage ranges and detection methods in research applications. Identification of alternate detection methods, hair types, and dosage rates could create new opportunities for RB use and potentially reduce adverse effects on target animals. We examined the relationship between hair types, dosage rate, and detection method for RB applications using black rats (Rattus rattus) in laboratory settings. We gave study animals varying doses of RB, and examined vibrissae and guard hairs for the detection of RB bands using ambient light, ultraviolet (UV) light, and fluorescence microscopy techniques. Fluorescence microscopy detected more RB marked hairs than UV light or ambient light. Fluorescence microscopy was more sensitive to RB dose rate detection; with receiver operating characteristic curves suggesting that the minimum dose rates at which RB intake can be correctly detected are 3.9 and 33 mg/kg for vibrissae and guard hairs, respectively. Guard hair RB detection was less reliable under ambient light and UV lamps, but equally detectable as vibrissae under fluorescence microscopy. Our results confirmed the interrelationship between dosage and detection methods in the efficacy of bait markers. We demonstrated that guard hairs can be a reliable hair type for the detection of RB. This application is less invasive than sampling animal tissues to detect bait uptake. © 2012 The Wildlife Society.     

Insights into Negative Regulation by the Glucocorticoid Receptor from Genome-wide Profiling of Inflammatory Cistromes

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Highlights? TLR4 activation dramatically remodels the GR cistrome in macrophages ? Both negative and positive GR enhancers include GREs, NF-κB, and AP-1 sites ? Classical models fail to predict positive or negative polarity of GR regulation ? Hormone treatment marks negative enhancers by histone deacetylation     

Exercise and PGC-1α-independent synchronization of type I muscle metabolism and vasculature by ERRγ

How type I skeletal muscle inherently maintains high oxidative and vascular capacity in the absence of exercise is unclear. We show that nuclear receptor ERRγ is highly expressed in type I muscle and, when transgenically expressed in anaerobic type II muscles (ERRGO mice), dually induces metabolic and vascular transformation in the absence of exercise. ERRGO mice show increased expression of genes promoting fat metabolism, mitochondrial respiration, and type I fiber specification. Muscles in ERRGO mice also display an activated angiogenic program marked by myofibrillar induction and secretion of proangiogenic factors, neovascularization, and a 100% increase in running endurance. Surprisingly, the induction of type I muscle properties by ERRγ does not involve PGC-1α. Instead, ERRγ genetically activates the energy sensor AMPK in mediating the metabovascular changes in ERRGO mice. Therefore, ERRγ represents a previously unrecognized determinant that specifies intrinsic vascular and oxidative metabolic features that distinguish type I from type II muscle.