Project description:To identify transcriptional markers for beef traits related to meat tenderness and moisture, we measured the transcriptome of the Longissimus dorsi skeletal muscle in 10 Korean native cattle (KNC). We analyzed the correlation between the beef transcriptome and measurements of four different beef traits, shear force (SF), water holding capacity (WHC), cooking loss (CL), and loin eye area (LEA). We obtained non-overlapping and unique panels of genes showing strong correlations (|r| > 0.8) with SF, WHC, CL, and LEA, respectively. Functional studies of these genes indicated that SF was mainly related to energy metabolism, and LEA to rRNA processing. Interestingly, our data suggested that WHC is influenced by protein metabolism. Overall, the skeletal muscle transcriptome pointed to the importance of energy and protein metabolism in determining meat quality after the aging process. The panels of transcripts for beef traits may be useful for predicting meat tenderness and moisture. Experiment Overall Design: Gene expression profiles were correlated with beef traits measured at the same cattle.
Project description:We hypothesized that the relative abundances of host cell transcripts in lymph nodes of animals with malignant catarrhal fever (MCF), compared to healthy controls, may be used to identify pathways that may help to explain the pathogenesis of MCF. Therefore, an abundance of host cell gene expression patterns in lymph nodes of animals with MCF and healthy controls were analyzed by microarray. Indeed, a vast number of genes related to inflammatory processes, lymphocyte activation, cell proliferation and apoptosis were detected at different abundances. However, the IL-2 transcript was eminent among the transcripts, which were, compared to healthy controls, less abundant in animals with MCF. Compared to healthy cattle, bovines with MCF appear to mimic an IL-2 knockout phenotype that has been described in mice. This supports the hypothesis that immunopathogenic events are linked to the pathogenesis of MCF. IL-2-deficiency may play an important role in the process. Keywords: disease state analysis
Project description:cDNA microarrays have been shown to be useful for monitoring global gene expression patterns in normal and disease states and in response to various environmental stimuli. In this study we have used a cattle cDNA microarray containing 7653 elements to analyze expression profiles in 19 different cattle tissues. Signal intensities from all tissue sample RNAs were compared to a reference standard RNA created from different tissues and cell lines. Data analysis identified a subset of genes significantly differentially expressed between tissues and the reference standard that were further subdivided according to fold change. Log transformed ratios were normalized using the intensity-based regional Lowess algorithm. A global error model, to account for the dependence of variation on signal intensities, was used to identify lists of genes for effect of tissue on gene expression taking into account an experiment-wise significance of 0.05, using either a Bonferroni correction (663 genes) or Benjamini and Hochbergâ??s False Discovery Rate (3350 genes). Non-supervised cluster analysis revealed groups of genes common to nerve, muscle, immune or digestive tissues. Discriminant analysis was used to support physiological functional categories and embryonic origin of tissues. Unique profiles were constructed with genes preferentially expressed in specific tissues or tissue groups in order to define gene expression for individual tissues. Global expression along a large collection of tissues revealed tissue specific expression of enzyme isomers and utilization in specific metabolic pathways. A comprehensive matrix of all possible pair-wise comparisons for individual genes among tissues was constructed to further identify genes with tissue-specific behavior and possibly unique function. A reference design was used to compare 19 cattle tissues. All tissues were compared to a universal control consisting of a mix of cattle cell lines. All samples were duplicated with a dye swap.
Project description:With regulatory roles in development, cell proliferation and disease, micro-RNA (miRNA) biology is of great importance and a potential key to novel RNA-based therapeutic regimens. Biochemically based sequencing approaches have provided robust means of uncovering miRNA binding landscapes on transcriptomes of various species. However, a current limitation to the therapeutic potential of miRNA biology in cattle is the lack of validated miRNAs targets. Here, we use cross-linking immunoprecipitation (CLIP) of the Argonaute (AGO) proteins and unambiguous miRNA-target identification through RNA chimeras to define a regulatory map of miRNA interactions in the cow (Bos taurus). The resulting interactome is the deepest reported to date for any species, demonstrating that comprehensive maps can be empirically obtained. We observe that bovine miRNA targeting principles are consistent with those observed in other mammals. Motif and structural analyses define expanded pairing rules with most interactions combining seed-based pairing with distinct, miRNA-specific patterns of auxiliary pairing. Further, miRNA-target chimeras had predictive value in evaluating true regulatory sites of the miR-17 family. Finally, we define miRNA-specific targeting for >5000 mRNAs and determine gene ontologies (GO) for these targets. This confirmed repression of genes important for embryonic development and cell cycle progress by the let-7 family, and repression of those involved in cell cycle arrest by the miR-17 family, but it also suggested a number of unappreciated miRNA functions. Our results provide a significant resource for transcriptomic understanding of bovine miRNA regulation, and demonstrate the power of experimental methods for establishing comprehensive interaction maps.