@article{SchwahnBeleggiaOmranianetal.2017, author = {Schwahn, Kevin and Beleggia, Romina and Omranian, Nooshin and Nikoloski, Zoran}, title = {Stoichiometric Correlation Analysis: Principles of Metabolic Functionality from Metabolomics Data}, series = {Frontiers in plant science}, volume = {8}, journal = {Frontiers in plant science}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-462X}, doi = {10.3389/fpls.2017.02152}, pages = {12}, year = {2017}, abstract = {Recent advances in metabolomics technologies have resulted in high-quality (time-resolved) metabolic profiles with an increasing coverage of metabolic pathways. These data profiles represent read-outs from often non-linear dynamics of metabolic networks. Yet, metabolic profiles have largely been explored with regression-based approaches that only capture linear relationships, rendering it difficult to determine the extent to which the data reflect the underlying reaction rates and their couplings. Here we propose an approach termed Stoichiometric Correlation Analysis (SCA) based on correlation between positive linear combinations of log-transformed metabolic profiles. The log-transformation is due to the evidence that metabolic networks can be modeled by mass action law and kinetics derived from it. Unlike the existing approaches which establish a relation between pairs of metabolites, SCA facilitates the discovery of higherorder dependence between more than two metabolites. By using a paradigmatic model of the tricarboxylic acid cycle we show that the higher-order dependence reflects the coupling of concentration of reactant complexes, capturing the subtle difference between the employed enzyme kinetics. Using time-resolved metabolic profiles from Arabidopsis thaliana and Escherichia coli, we show that SCA can be used to quantify the difference in coupling of reactant complexes, and hence, reaction rates, underlying the stringent response in these model organisms. By using SCA with data from natural variation of wild and domesticated wheat and tomato accession, we demonstrate that the domestication is accompanied by loss of such couplings, in these species. Therefore, application of SCA to metabolomics data from natural variation in wild and domesticated populations provides a mechanistic way to understanding domestication and its relation to metabolic networks.}, language = {en} } @article{LudwigReissmannBeneckeetal.2015, author = {Ludwig, Arne and Reissmann, Monika and Benecke, Norbert and Bellone, Rebecca and Sandoval-Castellanos, Edson and Cieslak, Michael and Gonz{\´a}lez-Fortes, Gloria M. and Morales-Muniz, Arturo and Hofreiter, Michael and Pruvost, Melanie}, title = {Twenty-five thousand years of fluctuating selection on leopard complex spotting and congenital night blindness in horses}, series = {Philosophical transactions of the Royal Society of London : B, Biological sciences}, volume = {370}, journal = {Philosophical transactions of the Royal Society of London : B, Biological sciences}, number = {1660}, publisher = {Royal Society}, address = {London}, issn = {0962-8436}, doi = {10.1098/rstb.2013.0386}, pages = {7}, year = {2015}, abstract = {Leopard complex spotting is inherited by the incompletely dominant locus, LP, which also causes congenital stationary night blindness in homozygous horses. We investigated an associated single nucleotide polymorphism in the TRPM1 gene in 96 archaeological bones from 31 localities from Late Pleistocene (approx. 17 000 YBP) to medieval times. The first genetic evidence of LP spotting in Europe dates back to the Pleistocene. We tested for temporal changes in the LP associated allele frequency and estimated coefficients of selection by means of approximate Bayesian computation analyses. Our results show that at least some of the observed frequency changes are congruent with shifts in artificial selection pressure for the leopard complex spotting phenotype. In early domestic horses from Kirklareli-Kanligecit (Turkey) dating to 2700-2200 BC, a remarkably high number of leopard spotted horses (six of 10 individuals) was detected including one adult homozygote. However, LP seems to have largely disappeared during the late Bronze Age, suggesting selection against this phenotype in early domestic horses. During the Iron Age, LP reappeared, probably by reintroduction into the domestic gene pool from wild animals. This picture of alternating selective regimes might explain how genetic diversity was maintained in domestic animals despite selection for specific traits at different times.}, language = {en} } @article{Ogone2015, author = {Ogone, James Odhiambo}, title = {Remediating orality: the cultural domestication of video technology in Kenya}, series = {Critical arts : a journal for cultural studies}, volume = {29}, journal = {Critical arts : a journal for cultural studies}, number = {4}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {0256-0046}, doi = {10.1080/02560046.2015.1078541}, pages = {479 -- 495}, year = {2015}, abstract = {The influence of globalisation and its attendant modern technologies has reconfigured the manner in which orality functions in the contemporary African context. Confronted with the powerful presence of media technologies that threaten to supplant its central role in many African societies, orality has been compelled to reinvent itself by means of appropriating the same media for its survival. The result has been a process that seeks to recontextualise imported technologies in locally relevant ways. This article focuses on how video technology adapts to local Kenyan cultural contexts. Arguing that vernacular video films form part of contemporary cultural productions in Kenya, the article demonstrates how strategies of remediation, such as subtitling, re-oralisation, repurposing and immediacy, contribute to the reactivation of orality. It emerges from the analyses that local knowledge cultures actively engage modern technologies in a way that debunks any simple linear perceptions of the impact of mediatisation on African epistemologies. Through local agency, communities actualise their aspirations for a domesticated modernity that is simultaneously fresh and familiar, and therefore less culturally alienating.}, language = {en} } @article{XiangGaoYuetal.2014, author = {Xiang, Hai and Gao, Jianqiang and Yu, Baoquan and Zhou, Hui and Cai, Dawei and Zhang, Youwen and Chen, Xiaoyong and Wang, Xi and Hofreiter, Michael and Zhao, Xingbo}, title = {Early Holocene chicken domestication in northern China}, series = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {111}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, number = {49}, publisher = {National Acad. of Sciences}, address = {Washington}, issn = {0027-8424}, doi = {10.1073/pnas.1411882111}, pages = {17564 -- 17569}, year = {2014}, abstract = {Chickens represent by far the most important poultry species, yet the number, locations, and timings of their domestication have remained controversial for more than a century. Here we report ancient mitochondrial DNA sequences from the earliest archaeological chicken bones from China, dating back to similar to 10,000 B.P. The results clearly show that all investigated bones, including the oldest from the Nanzhuangtou site, are derived from the genus Gallus, rather than any other related genus, such as Phasianus. Our analyses also suggest that northern China represents one region of the earliest chicken domestication, possibly dating as early as 10,000 y B.P. Similar to the evidence from pig domestication, our results suggest that these early domesticated chickens contributed to the gene pool of modern chicken populations. Moreover, our results support the idea that multiple members of the genus Gallus, specifically Gallus gallus and Gallus sonneratii contributed to the gene pool of the modern domestic chicken. Our results provide further support for the growing evidence of an early mixed agricultural complex in northern China.}, language = {en} } @phdthesis{Wutke2016, author = {Wutke, Saskia}, title = {Tracing Changes in Space and Time}, school = {Universit{\"a}t Potsdam}, pages = {x, 84}, year = {2016}, abstract = {The horse is a fascinating animal symbolizing power, beauty, strength and grace. Among all the animal species domesticated the horse had the largest impact on the course of human history due to its importance for warfare and transportation. Studying the process of horse domestication contributes to the knowledge about the history of horses and even of our own species. Research based on molecular methods has increasingly focused on the genetic basis of horse domestication. Mitochondrial DNA (mtDNA) analyses of modern and ancient horses detected immense maternal diversity, probably due to many mares that contributed to the domestic population. However, mtDNA does not provide an informative phylogeographic structure. In contrast, Y chromosome analyses displayed almost complete uniformity in modern stallions but relatively high diversity in a few ancient horses. Further molecular markers that seem to be well suited to infer the domestication history of horses or genetic and phenotypic changes during this process are loci associated with phenotypic traits. This doctoral thesis consists of three different parts for which I analyzed various single nucleotide polymorphisms (SNPs) associated with coat color, locomotion or Y chromosomal variation of horses. These SNPs were genotyped in 350 ancient horses from the Chalcolithic (5,000 BC) to the Middle Ages (11th century). The distribution of the samples ranges from China to the Iberian Peninsula and Iceland. By applying multiplexed next-generation sequencing (NGS) I sequenced short amplicons covering the relevant positions: i) eight coat-color-associated mutations in six genes to deduce the coat color phenotype; ii) the so-called 'Gait-keeper' SNP in the DMRT3 gene to screen for the ability to amble; iii) 16 SNPs previously detected in ancient horses to infer the corresponding haplotype. Based on these data I investigated the occurrence and frequencies of alleles underlying the respective phenotypes as well as Y chromosome haplotypes at different times and regions. Also, selection coefficients for several Y chromosome lineages or phenotypes were estimated. Concerning coat color differences in ancient horses my work constitutes the most comprehensive study to date. I detected an increase of chestnut horses in the Middle Ages as well as differential selection for spotted and solid phenotypes over time which reflects changing human preferences. With regard to ambling horses, the corresponding allele was present in medieval English and Icelandic horses. Based on these results I argue that Norse settlers, who frequently invaded parts of Britain, brought ambling individuals to Iceland from the British Isles which can be regarded the origin of this trait. Moreover, these settlers appear to have selected for ambling in Icelandic horses. Relating to the third trait, the paternal diversity, these findings represent the largest ancient dataset of Y chromosome variation in non-humans. I proved the existence of several Y chromosome haplotypes in early domestic horses. The decline of Y chromosome variation coincides with the movement of nomadic peoples from the Eurasian steppes and later with different breeding practices in the Roman period. In conclusion, positive selection was estimated for several phenotypes/lineages in different regions or times which indicates that these were preferred by humans. Furthermore, I could successfully infer the distribution and dispersal of horses in association with human movements and actions. Thereby, a better understanding of the influence of people on the changing appearance and genetic diversity of domestic horses could be gained. My results also emphasize the close relationship of ancient genetics and archeology or history and that only in combination well-founded conclusions can be reached.}, language = {en} }