Project description:Transcriptome analysis of ruminal epithelia revealed that potential regulatory mechanisms involved in host adaptation to rapid high fermentable dietary transition in beef cattle
Project description:Cattle shedding > 10e4 CFU of Escherichia coli O157 per g of feces are defined as super-shedders. RNA-sequencing was performed to identify the transcriptome of tissues, including duodenum, proximal jejunum, distal jejunum, distal jejunum, cecum, spiral colon and descending colon of super-shedder cattle in comparison with non-shedders. The total number of genes detected in gut tissues ranged from 16,846 ± 639 (cecum) to 18,137 ± 696 (distal jejunum), and immune functions were enriched for the transcriptomes of small intestinal tissues, reflecting their greater immune activity than large intestine. Totally 351 differentially expression genes were identified between super-shedders and non-shedders, including 101 up-regulated and 250 down-regulated in super-shedders. Differential gene expression analysis suggested increased T-cell responses and cholesterol absorption in distal jejunum and descending colon, and inhibited B-cell maturation in intestines of super-shedders. distal jejunum of super-shedders. Our findings suggested that host genetics and E. coli O157 activities are involved in super-shedding phenomenon.
Project description:The liver of dairy cows naturally displays a series of metabolic adaptation during the periparturient period in response to the increasing nutrient requirement of lactation. The hepatic adaptation is partly regulated by insulin resistance and it is affected by the prepartal energy intake level of cows. We aimed to investigate the metabolic changes in the liver of dairy cows during the periparturient at gene expression level and to study the effect of prepartal energy level on the metabolic adaptation at gene expression level.B13:N13
Project description:Tropical theileriosis in a cattle disease of global economic importance, caused by the tick-borne protozoan parasite Theileria annulata. Conventional control strategies are failing to contain the disease and an attractive alternative is the use of pre-existing genetic resistance or tolerance. However, tropical theileriosis tolerant cattle are less productive than some susceptible breeds. To combine resistance and production traits requires an understanding of the mechanisms involved in resistance. Therefore, we have compared the response of monocytes derived from tolerant (Sahiwals, Bos indicus) and susceptible (Holstein-Friesians, B. taurus) cattle to in vitro infection with T. annulata. Over 150 genes exhibited breed-specific differential expression during the course of infection and nearly one third were differentially expressed in resting cells, implying that there are inherent differences between monocytes from the breeds. Fifty sequences currently only match ESTs or are unique to the library used to generate the microarray. The differential expression of a selection of genes was validated by quantitative RT-PCR, e.g. CD9, prion protein and signal-regulatory protein alpha. A large proportion of the differentially expressed genes encode proteins expressed on the plasma membrane or in the extracellular space and cell adhesion was one of the major Gene Ontology biological processes identified. We therefore hypothesise that the breed-specific tolerance of Sahiwal cattle compared to Holstein-Friesians is due to the interaction of infected cells with other immune cells, which influences the immune response generated against T. annulata infection. The BoMP microarray is available from the ARK-Genomics facility (www.ark-genomics.org).
Project description:The current study aimed to investigate whether bovine non-coding RNA play a role in regulating E. coli O157 shedding through studying miRNAomes of the whole gastrointestinal tract including duodenum, proximal jejunum, distal jejunum, cecum, spiral colon, descending colon and rectum. The number of miRNAs detected in each intestinal region ranged from 390 ± 13 to 413 ± 49. Compared between SS and NS, the number of differentially expressed (DE) miRNAs ranged from one to eight, and through the whole gut, seven miRNAs were up-regulated and seven were down-regulated in SS. The distal jejunum and rectum were the regions where the most DE miRNAs were identified (8 and 7, respectively). Functional analysis indicated that the bta-miR-378b, bta-miR-2284j and bta-miR-2284d which were down-regulated in both distal jejunum and rectum of SS, the bta-miR-2887 which was down-regulated in rectum of SS, as well as the bta-miR-211 and bta-miR-29d-3p which were up-regulated in rectum of SS were potentially regulatory to host immune functions, including hematological system development and immune cell trafficking. Our findings suggest that the alternation of miRNA expression in the gut of SS may lead to differential regulation in immune functions involved in E. coli O157 super-shedding in cattle.
Project description:The current study aimed to investigate whether bovine non-coding RNA play a role in regulating E. coli O157 shedding through studying miRNAomes of the whole gastrointestinal tract including duodenum, proximal jejunum, distal jejunum, cecum, spiral colon, descending colon and rectum. The number of miRNAs detected in each intestinal region ranged from 390 ± 13 to 413 ± 49. Compared between SS and NS, the number of differentially expressed (DE) miRNAs ranged from one to eight, and through the whole gut, seven miRNAs were up-regulated and seven were down-regulated in SS. The distal jejunum and rectum were the regions where the most DE miRNAs were identified (8 and 7, respectively). Functional analysis indicated that the bta-miR-378b, bta-miR-2284j and bta-miR-2284d which were down-regulated in both distal jejunum and rectum of SS, the bta-miR-2887 which was down-regulated in rectum of SS, as well as the bta-miR-211 and bta-miR-29d-3p which were up-regulated in rectum of SS were potentially regulatory to host immune functions, including hematological system development and immune cell trafficking. Our findings suggest that the alternation of miRNA expression in the gut of SS may lead to differential regulation in immune functions involved in E. coli O157 super-shedding in cattle.