20:T416,The adipocyte-derived hormone adiponectin has been proposed to play important roles in the regulation of energy homeostasis and insulin sensitivity, and it has been reported to exhibit putative antiatherogenic properties in vitro. In this study we generated adiponectin-deficient mice to directly investigate whether adiponectin has a physiological protective role against diabetes and atherosclerosis in vivo. Heterozygous adiponectin-deficient (adipo ^+/−) mice showed mild insulin resistance, while homozygous adiponectin-deficient (adipo ^−/−) mice showed moderate insulin resistance with glucose intolerance despite body weight gain similar to that of wild-type mice. Moreover, adipo ^−/−mice showed 2-fold more neointimal formation in response to external vascular cuff injury than wild-type mice (p = 0.01). This study provides the first direct evidence that adiponectin plays a protective role against insulin resistance and atherosclerosis in vivo.21:T509,Adiponectin is a plasma protein expressed exclusively in adipose tissue. Adiponectin levels are linked to insulin sensitivity, but a direct effect of chronically elevated adiponectin on improved insulin sensitivity has not yet been demonstrated. We identified a dominant mutation in the collagenous domain of adiponectin that elevated circulating adiponectin values in mice by 3-fold. Adiponectinemia raised lipid clearance and lipoprotein lipase activity, and suppressed insulin-mediated endogenous glucose production. The induction of adiponectin during puberty and the sexual dimorphism in adult adiponectin values were preserved in these transgenic animals. As a result of elevated adiponectin, serum PRL values and brown adipose mass both increased. The effects on carbohydrate and lipid metabolism were associated with elevated phosphorylation of 5'-AMP-activated protein kinase in liver and elevated expression of peroxisomal proliferator-activated receptor gamma2, caveolin-1, and mitochondrial markers in white adipose tissue. These studies strongly suggest that increasing endogenous adiponectin levels has direct effects on insulin sensitivity and may induce similar physiological responses as prolonged treatment with peroxisomal proliferator-activated receptor gamma agonists.22:T550,Recent bioinformatics-aided searches have identified many new small RNAs (sRNAs) in the intergenic regions of the bacterium Escherichia coli. Here, a shot-gun cloning approach (RNomics) was used to generate cDNA libraries of small sized RNAs. Besides many of the known sRNAs, we found new species that were not predicted previously. The present work brings the number of sRNAs in E.coli to 62. Experimental transcription start site mapping showed that some sRNAs were encoded from independent genes, while others were processed from mRNA leaders or trailers, indicative of a parallel transcriptional output generating sRNAs co-expressed with mRNAs. Two of these RNAs (SroA and SroG) consist of known (THI and RFN) riboswitch elements. We also show that two recently identified sRNAs (RyeB and SraC/RyeA) interact, resulting in RNase III-dependent cleavage. To the best of our knowledge, this represents the first case of two non-coding RNAs interacting by a putative antisense mechanism. In addition, intracellular metabolic stabilities of sRNAs were determined, including ones from previous screens. The wide range of half-lives (<2 to >32 min) indicates that sRNAs cannot generally be assumed to be metabolically stable. The experimental characterization of sRNAs analyzed here suggests that the definition of an sRNA is more complex than previously assumed.23:T7b9,

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