Project description:Hanwoo cattle are a Korean breed renowned for their cultural significance and high-quality beef, characterized by low cholesterol and high unsaturated fat ratio. Growth is divided into a growing phase focused on development and a fattening phase for marbling. Proper feed management, considering genetic and environmental factors, is vital for maximizing growth potential. The rumen plays a crucial role in digestion and gene expression regulation, with rumen fermentation being central to nutrient absorption and cattle health. In this study, we conduct transcriptome analysis of the rumen at eight timepoints. Our goal is to identify genetic factors that influence the growth of Hanwoo steers to enhance our understanding of the rumen’s functions and roles during their growth. In this RNA-sequencing analysis of Hanwoo steer rumen, differential gene expression was examined over eight timepoints, highlighting significant genetic changes, particularly between 12 and 26 months. Weighted gene co-expression network analysis identified and organized as three modules: turquoise, blue, and yellow. The turquoise module, linked to immune response, showed down-regulation in genes at 30 months. The blue module, associated with steroid metabolism, was notably up-regulated at 26 months. The yellow module’s genes showed a consistent increase in expression with growth. These modules and their functional annotations provide a deeper understanding of the biological processes during Hanwoo growth, highlighting the intricate relationship between gene expression and cattle development. The growth stages of Hanwoo steers were explored in our investigation utilizing rumen transcriptome data. The rumen plays critical role in their development, particularly during the growing and fattening phases. Proper feed management, considering the rumen’s function, is essential for optimal growth. Transcriptome analysis helps identify genes associated with growth and provides insights for cattle breeding and management practices. Understanding the complex connection between gene expression and Hanwoo development is essential for maximizing productivity and health.
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:While genetic markers related to meat production traits have been identified in many other breeds of cattle, research on weight in Hanwoo cattle (Korean native cattle) has been relatively limited. In this study, we performed expression quantitative trait loci (eQTL) analysis and differential gene expression analysis to detect candidate genes influencing the weight characteristics of 32 castrated Hanwoo cattle across 22 tissues and identify variants that affect gene expression levels. In total, we identified a total of 2,465 differentially expressed genes, among which we discovered key genes such as UBD, RGS2, FASN, and SCD that have functions related to adipogenesis, body weight, obesity, and lipid metabolism. Gene-set enrichment analysis revealed that candidate genes in adipose tissue are involved in metabolic pathways related to Obesity-related traits, adipose metabolism, and lipid metabolism. Additionally, we found that decreased expression of TRIM31 contributes to weight gain which can be explained by the associated candidate cis-eQTL genotypes for TRIM31 and their effect on differential gene expression between the lower and higher weight groups. Our findings revealed candidate genes associated with the weight of Hanwoo cattle and perhaps can provide comprehensive insights into the association of weight with various tissues beyond adipose tissue and muscle, indicating the potential for expanding the focus of livestock trait research.
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.