Project description:Creatine pyruvate (CrPyr) is a new multifunctional nutrient that can provide both pyruvate and creatine. It has been shown to relieve the heat stress of beef cattle by improving antioxidant activity and rumen microbial protein synthesis, but the mechanism of CrPyr influencing rumen fermentation remains unclear. This study aimed to use metaproteomics technologies to investigate the bacterial protein function in rumen fluid samples taken from heat-stressed beef cattle treated with or without 60 g/d CrPyr.
Project description:As the unique organ, rumen plays vital roles in providing products for humans, however, the underlying cell composition and interactions with epithelium-attached microbes remain largely unknown. Herein, we performed an integrated analysis in single-cell transcriptome, epithelial microbiome, and metabolome of rumen tissues to explore the differences of microbiota-host crosstalk between newborn and adult cattle models. We found that fewer epithelial cell subtypes and more abundant immune cells (e.g., Th17 cells) in the rumen tissue of adult cattle. Metabolism-related functions and oxidation-reduction process were significantly upregulated in the adult rumen epithelial cell subtypes. The epithelial Desulfovibrio was significantly enriched in the adult cattle. To further clarify the role of Desulfovibrio in host’s oxidation-reduction process, we performed metabolomics analysis of rumen tissues and found that Desulfovibrio showed a high co-occurrence probability with the pyridoxal in the adult cattle compared with newborn ones. The adult rumen epithelial cell subtypes also showed stronger ability of pyridoxal binding. These indicates that Desulfovibrio and pyridoxal likely play important roles in maintaining redox balance in adult rumen. The integrated analysis provides novel insights into the understanding of rumen function and facilitate the future precision improvement of rumen function and milk/meat production in cattle.
Project description:The transcriptome of Escherichia coli K-12 has been widely studied over a variety of conditions for the past decade while such studies involving E. coli O157:H7, its pathogenic cousin, are just now being conducted. To better understand the impact of rumen fluid on E. coli O157:H7, global transcript levels of strain EDL933 cells resuspended in heat clarified rumen fluid for 15 min were compared to cells resuspended in fresh LB using microarrays. Seven independent RNA samples from rumen fluid treated cultures were paired with seven independent RNA samples from control cultures for hybridization to seven two-color microarrays. For three arrays, the control RNA sample was labeled with Cy3 dye and the experimental RNA sample was labeled with Cy5 dye, the dyes were reversed for the other four arrays to overcome dye bias.
Project description:Investigation of whole genome gene expression level changes in rumen epithelium of dairy cattle at different stages of rumen development and on different diets.
Project description:In this study, we generated genome-wide data sets for four histone modifications, including H3K9ac, H3K27ac, RNA pol II, H3K9me3,, which were collected from rumen tissues before and after Butyrate treatment. By combining other types of data sets collected in Rumen Epithelial Primary Cells (REPC) , inclduing four histone codes, CTCF, DNA accessibility, DNA methylation, and RNA-seq, we established and validated the first global map of regulatory elements (15 chromatin states) and defined their coordinated activities in cattle. We, for the first time, were able to establish the correlation among nutritional elements, chromatin states, gene activities, and phenotypic outcomes.