University of Hohenheim

About: University of Hohenheim is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Population & Soil water. The organization has 8585 authors who have published 16406 publications receiving 567377 citations.

The genomes of two key bumblebee species with primitive eusocial organization

Abstract: The shift from solitary to social behavior is one of the major evolutionary transitions Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Endogenous Arabidopsis messenger RNAs transported to distant tissues

Abstract: The concept that proteins and small RNAs can move to and function in distant body parts is well established. However, non-cell-autonomy of small RNA molecules raises the question: To what extent are protein-coding messenger RNAs (mRNAs) exchanged between tissues in plants? Here we report the comprehensive identification of 2,006 genes producing mobile RNAs in Arabidopsis thaliana. The analysis of variant ecotype transcripts that were present in heterografted plants allowed the identification of mRNAs moving between various organs under normal or nutrient-limiting conditions. Most of these mobile transcripts seem to follow the phloem-dependent allocation pathway transporting sugars from photosynthetic tissues to roots via the vasculature. Notably, a high number of transcripts also move in the opposite, root-to-shoot direction and are transported to specific tissues including flowers. Proteomic data on grafted plants indicate the presence of proteins from mobile RNAs, allowing the possibility that they may be translated at their destination site. The mobility of a high number of mRNAs suggests that a postulated tissue-specific gene expression profile might not be predictive for the actual plant body part in which a transcript exerts its function.

Potential nutritional and physiological functions of betaine in livestock

Abstract: The present review summarises the potential nutritional and physiological functions of betaine as a feed additive in relation to performance criteria in livestock production. Betaine, the trimethyl derivative of the amino acid glycine, is a metabolite of plant and animal tissues. In plants, betaine is particularly synthesised and accumulated as an osmoprotectant against salt and temperature stress. In animals, betaine is the product of choline oxidation or it originates from nutritional sources. Over the past decades, numerous studies have been carried out to investigate the potential effects of betaine supplementation on animal performance. Due to its chemical structure, betaine shows the characteristics of a dipolar zwitterion resulting in osmoprotective properties. Promoting effects on the intestinal tract against osmotic stress occurring during diarrhoea or coccidiosis have been reported following betaine supplementation in pigs and poultry. There is also some evidence that dietary betaine may improve the digestibility of specific nutrients. As a product of choline oxidation, betaine is involved in transmethylation reactions of the organism. Betaine as a methyl donor provides its labile methyl groups for the synthesis of several metabolically active substances such as creatine and carnitine. Supplementation with betaine may decrease the requirement for other methyl donors such as methionine and choline. There is also some evidence for enhanced methionine availability after dietary supplementation of betaine resulting in improved animal performance. Alterations in the distribution pattern of protein and fat in the body have been reported following betaine supplementation. A more efficient use of dietary protein may result from a methionine-sparing effect of betaine, but also direct interactions of betaine with metabolism-regulating factors have to be considered. Though the mode of action of betaine as a carcass modifier remains open, there is, however, growing evidence that betaine could have a positive impact both on animal performance and carcass quality.

Meta-Analysis of the Relationship Between the Big Five and Academic Success at University

Abstract: . Interest in the prediction of academic success in higher education has grown considerably in recent years in German-speaking countries. While the validity of school grades and admission tests has been investigated by meta-analyses and large-scale studies at least in the United States, less is known about noncognitive predictors of academic success. The present meta-analysis investigates the impact of the Big Five personality factors on academic success at university. A total of 258 correlation coefficients from 58 studies published since 1980 were included. Grades, retention, and satisfaction served as success criteria. Correlations were corrected for attenuation caused by measurement error. Results show that the influence of personality traits on academic achievement depends on the success criterion. While Neuroticism is related to academic satisfaction (? = -.369, k = 8), Conscientiousness correlates with grades (? = .269, k = 41). Extraversion, Openness to Experience, and Agreeableness have n...

Similar estimates of temperature impacts on global wheat yield by three independent methods

Abstract: The potential impact of global temperature change on global crop yield has recently been assessed with different methods. Here we show that grid-based and point-based simulations and statistical regressions (from historic records), without deliberate adaptation or CO 2 fertilization effects, produce similar estimates of temperature impact on wheat yields at global and national scales. With a 1 °C global temperature increase, global wheat yield is projected to decline between 4.1% and 6.4%. Projected relative temperature impacts from different methods were similar for major wheat-producing countries China, India, USA and France, but less so for Russia. Point-based and grid-based simulations, and to some extent the statistical regressions, were consistent in projecting that warmer regions are likely to suffer more yield loss with increasing temperature than cooler regions. By forming a multi-method ensemble, it was possible to quantify 'method uncertainty' in addition to model uncertainty. This significantly improves confidence in estimates of climate impacts on global food security.