|LI, YAOKUN - Northwest Agriculture And Forestry University
|CARRILLO, JOSE - University Of Maryland
|DING, YI - University Of Maryland
|HE, YANGHUA - University Of Maryland
|ZHAO, CHUNPING - Northwest Agriculture And Forestry University
|LUI, JIANAN - University Of Maryland
|Liu, Ge - George
|ZAN, LINSEN - Northwest Agriculture And Forestry University
|SONG, JIUZHOU - University Of Maryland
Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/27/2015
Publication Date: 9/14/2015
Citation: Li, Y., Carrillo, J.A., Ding, Y., He, Y., Zhao, C., Lui, J., Liu, G., Zan, L., Song, J. 2015. Transcriptomic profiling of spleen in grass-fed and grain-fed Angus cattle. PLoS One. 10(9):e0135670.
Interpretive Summary: Beef growth and meat quality are economically important traits. In this project, we tested the hypothesis that the spleen might exhibit distinct characteristics under grass-fed and grain-fed regimes that affect immune function of cattle. We sampled spleen tissues from grass-fed and grain-fed Angus cattle and performed a comparative study of gene expression using RNA-Seq methodology. Based on the differentially expressed genes, we did a functional analysis and identified potential mechanisms that could contribute to the difference observed between these two feeding regimens. Farmers, scientist, and policy planners who need to improve animal health and production based on genome-enable animal selection will benefit from this work.
Technical Abstract: The grass-fed cattle obtain nutrients directly from pastures containing limited assimilable energy but abundant amount of fiber; by contrast, grain-fed steers receive a diet that is comprised mainly of grains and serves as an efficient source of high-digestible energy. Besides energy, these two types of diet differ in a large number of nutritional components. Additionally, animals maintained on rich-energy regimen are more likely to develop metabolic disorders and infectious diseases than pasture raised individuals. Thus, we hypothesize that spleen–a relevant immune organ–may function differently under disparate regimes. The objective of this study was to find the differentially expressed genes in the spleen of grass-fed and grain-fed steers, and furtherly explore the potential involved biopathways. Through RNA sequencing (RNA-Seq), we detected 123 differentially expressed genes. Based on these genes, we performed an Ingenuity Pathway Analysis (IPA) and identified 9 significant molecular networks and 13 enriched biological pathways. Two of the pathways, Nur77 signaling in T lymphocytes and calcium-induced T lymphocyte apoptosis which are immune related, contain a pair of genes HLA-DRA and NR4A1 with dramatically altered expression level. Collectively, our results provided valuable insights into understanding the molecular mechanism of spleen under varied feeding regimens.