Project description:The origins, prevalence and nature of dairying have been long debated by archaeologists. Within the last decade, new advances in high-resolution mass spectrometry have allowed for the direct detection of milk proteins from archaeological remains, including ceramics, dental calculus, and preserved dairy products. Proteins recovered from archaeological remains are susceptible to post-excavation and laboratory contamination, a particular concern for ancient dairying studies as milk proteins are potential laboratory contaminants. Here, we examine how site-specific rates of deamidation can be used to elucidate patterns of peptide degradation, and authenticate ancient milk proteins. First, we characterize site-specific deamidation patterns in modern milk products and experimental samples, confirming that deamidation occurs primarily at low half-time sites. We then compare this to previously published ancient proteomic data from six studies reporting ancient milk peptides. We confirm that site-specific deamidation rates, on average, are more advanced in beta-lactoglobulin recovered from ancient dental calculus and pottery residues. Nevertheless, deamidation rates displayed a high degree of variability, making it challenging to authenticate samples with relatively few milk peptides. We demonstrate that site-specific deamidation is a useful tool for identifying modern contamination but highlight the need for multiple lines of evidence to authenticate ancient protein data.
Project description:How and when the Americas were populated remains contentious. Using ancient and modern genome-wide data, we find that the ancestors of all present-day Native Americans, including Athabascans and Amerindians, entered the Americas as a single migration wave from Siberia no earlier than 23 thousand years ago (KYA), and after no more than 8,000-year isolation period in Beringia. Native Americans diversified into two basal genetic branches around 13 KYA, one in North and South America and the other restricted to North America. Subsequent gene flow resulted in some Native Americans sharing ancestry with present-day East Asians and Australo-Melanesians, the latter possibly through the ancestors of Aleutian Islanders. Putative relict populations in South America, including the historical Pericúes and Fuego-Patagonians, are not directly related to modern Australo-Melanesians.
Project description:This research examines animal teeth from Early Dynastic (2900-2350 BC) Mesopotamia (Southern Iraq) to assess animal management practices and identify consumption patterns in animal diets. The objective to answer larger questions about food management and environmental resilience in ancient early complex societies in the Near East was achieved by the use of mass spectrometry-based proteomics for dietary reconstruction. Dietary MS, a revolutionary new methodology applying proteomics techniques to archaeological sample sets to reconstruct ancient animal diet. A developed protein extraction technique followed by liquid chromatography tandem mass spectrometry allowed the identification of the specific plant species consumed in order to highlight variable herd management strategies, resource optimization, for each taxon over time. It also provided information on overall health and indications of disease. This is the first study to apply a full suite of analyses to the region and provides the foundations of a necessary long-term view of human interaction within an environment through both time and space.
Project description:The Amish and Hutterites are U.S. farming populations with remarkably similar lifestyles. However, the Amish follow traditional farming practices, while the Hutterites employ modern farming techniques, and also show striking differences in asthma prevalence. Little is known about immune responses underlying these differences. To address this, we obtained genome-wide gene expression data in peripheral blood leukocytes from Amish and Hutterite schoolchildren.
Project description:Domestication caused significant differences in morphology and behavior between wild and domestic animals, and gene expression changes played an important role in this event. circRNA is a class of non-coding RNA that exerts a wide range of functions in biological processes through the regulation of gene expression. However, the regulatory role of circRNA in the process of domestication is still unclear. Here, we analyzed circRNA expression patterns in the prefrontal cortices of wild boar and domestic pig to determine the potential role of circRNAs in domestication. We identified a total of 11,375 circRNAs and found that 349 and 354 circRNAs were up-regulated in wild boar and Rongchang pig, respectively. This study lays the groundwork for exploring the regulatory role of circRNA in the process of domestication and provides new insights that contribute to further investigation of the molecular mechanism of pig domestication.
Project description:Transposable elements (TEs) are genomic parasites that constitute the most abundant portions of higher plant genomes. However, whether TE selection occurred during crop domestication remains unknown. HUO is active under normal growth conditions, present at low copy numbers, inserts preferentially into regions capable of transcription, but absent in almost all modern varieties, indicating its removal during rice domestication and modern rice breeding. HUO triggers genomic immunity and dramatically alters genome-wide methylation levels and small RNA biogenesis, as well as global gene expression. Its presence specifically affects agronomic traits by decreasing yield performance and disease resistance but enhancing salt tolerance, which mechanistically explains its domestication removal. Thus, our study reveals a unique retrotransposon as a negative target for maintaining genetic and epigenetic stability during crop domestication and selection.
Project description:Transposable elements (TEs) are genomic parasites that constitute the most abundant portions of higher plant genomes. However, whether TE selection occurred during crop domestication remains unknown. HUO is active under normal growth conditions, present at low copy numbers, inserts preferentially into regions capable of transcription, but absent in almost all modern varieties, indicating its removal during rice domestication and modern rice breeding. HUO triggers genomic immunity and dramatically alters genome-wide methylation levels and small RNA biogenesis, as well as global gene expression. Its presence specifically affects agronomic traits by decreasing yield performance and disease resistance but enhancing salt tolerance, which mechanistically explains its domestication removal. Thus, our study reveals a unique retrotransposon as a negative target for maintaining genetic and epigenetic stability during crop domestication and selection.
Project description:Transposable elements (TEs) are genomic parasites that constitute the most abundant portions of higher plant genomes. However, whether TE selection occurred during crop domestication remains unknown. HUO is active under normal growth conditions, present at low copy numbers, inserts preferentially into regions capable of transcription, but absent in almost all modern varieties, indicating its removal during rice domestication and modern rice breeding. HUO triggers genomic immunity and dramatically alters genome-wide methylation levels and small RNA biogenesis, as well as global gene expression. Its presence specifically affects agronomic traits by decreasing yield performance and disease resistance but enhancing salt tolerance, which mechanistically explains its domestication removal. Thus, our study reveals a unique retrotransposon as a negative target for maintaining genetic and epigenetic stability during crop domestication and selection.
Project description:Transposable elements (TEs) are genomic parasites that constitute the most abundant portions of higher plant genomes. However, whether TE selection occurred during crop domestication remains unknown. HUO is active under normal growth conditions, present at low copy numbers, inserts preferentially into regions capable of transcription, but absent in almost all modern varieties, indicating its removal during rice domestication and modern rice breeding. HUO triggers genomic immunity and dramatically alters genome-wide methylation levels and small RNA biogenesis, as well as global gene expression. Its presence specifically affects agronomic traits by decreasing yield performance and disease resistance but enhancing salt tolerance, which mechanistically explains its domestication removal. Thus, our study reveals a unique retrotransposon as a negative target for maintaining genetic and epigenetic stability during crop domestication and selection.