Invariance and plasticity in the Drosophila melanogaster metabolomic network in response to temperature

BACKGROUND: Metabolomic responses to extreme thermal stress have recently been investigated in Drosophila melanogaster. However, a network level understanding of metabolomic responses to longer and less drastic temperature changes, which more closely reflect variation in natural ambient temperatures experienced during development and adulthood, is currently lacking. Here we use high-resolution, non-targeted metabolomics to dissect metabolomic changes in D. melanogaster elicited by moderately cool (18°C) or warm (27°C) developmental and adult temperature exposures. RESULTS: We find that temperature at which larvae are reared has a dramatic effect on metabolomic network structure measured in adults. Using network analysis, we are able to identify modules that are highly differentially expressed in response to changing developmental temperature, as well as modules whose correlation structure is strongly preserved across temperature. CONCLUSIONS: Our results suggest that the effect of temperature on the metabolome provides an easily studied and powerful model for understanding the forces that influence invariance and plasticity in biological networks. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12918-014-0139-6) contains supplementary material, which is available to authorized users

Metabolic Characterization of the Common Marmoset (Callithrix jacchus)

High-resolution metabolomics has created opportunity to integrate nutrition and metabolism into genetic studies to improve understanding of the diverse radiation of primate species. At present, however, there is very little information to help guide experimental design for study of wild populations. In a previous non-targeted metabolomics study of common marmosets (Callithrix jacchus), Rhesus macaques, humans, and four non-primate mammalian species, we found that essential amino acids (AA) and other central metabolites had interspecies variation similar to intraspecies variation while non-essential AA, environmental chemicals and catabolic waste products had greater interspecies variation. The present study was designed to test whether 55 plasma metabolites, including both nutritionally essential and non-essential metabolites and catabolic products, differ in concentration in common marmosets and humans. Significant differences were present for more than half of the metabolites analyzed and included AA, vitamins and central lipid metabolites, as well as for catabolic products of AA, nucleotides, energy metabolism and heme. Three environmental chemicals were present at low nanomolar concentrations but did not differ between species. Sex and age differences in marmosets were present for AA and nucleotide metabolism and warrant additional study. Overall, the results suggest that quantitative, targeted metabolomics can provide a useful complement to non-targeted metabolomics for studies of diet and environment interactions in primate evolution.National Institutes of Health (U.S.) (grant AG038746

Redistribution with Sloth—Britain's problem?

SUMMARY Many if not most analyses of Britain's economic difficulties suggest that slow growth is at the heart of the problem—and an acceleration of growth the obvious cure. Past experience in Britain and in the Third World casts doubts on this. The eradication of unemployment poverty and other social problems depends as much on structural change as on growth. Economic policy, therefore, needs to be directed much more explicitly towards what is needed to restructure the British economy in the short and over the longer run. It is not even clear that aggregate growth has more than a minor part to play in the process. RESUME La redistribution paresseuse—le problème britannique? Plusieurs, sinon la plupart, des analyses des difficultés économiques britanniques placent la lenteur du développement au coeur du problème—et proposent l'accélération du développement comme remède évident. Cette théorie est mise en question par l'expérience vécue en Grande?Bretagne ainsi que dans le Tiers Monde. L'élimination du chômage, de la pauvreté et d'autres problèmes sociaux dépend autant de l'évolution structurale que de la croissance. La politique économique devrait, par conséquent, s'orienter beaucoup plus explicitement vers ce qui est nécessaire à la restructuration de l'économie britannique à courte et à longue échéance. Il n'est même pas évident que la croissance globale ait autre qu'un rôle mineur dans le processus. RESUMEN La lentitud en la redistribución, uno de los problemas principales de la Gran Bretaña de hoy Muchos, si no la mayoría de los análisis de las dificultades económicas de la Gran Bretaña, sugieren que el problema fundamental es su desarrollo demasiado lento y que la solución se halla en una aceleración del crecimiento. Esta afirmación parece ser ociosa a la vista de la experiencia pasada de la Gran Bretaña y del Tercer Mundo. La supresión del paro, la pobreza y otros problemas sociales depende tanto de los cambios estructurales como del crecimiento. La política económica, así pues, debería orientarse hacia una reestructuración de la economía británica, tanto a corto como a largo plazo. El crecimiento de conjunto no parece tener más que escasa importancia en este proceso