Submitted to: Frontiers in Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/14/2018
Publication Date: 7/4/2018
Citation: Taxis, T.M., Kehrli Jr, M.E., D'Orey-Branco, R., Casas, E. 2018. Association of transfer RNA fragments in white blood cells with antibody response to bovine leukemia virus in holstein cattle. Frontiers in Genetics. 9:236. https://doi.org/10.3389/fgene.2018.00236.
DOI: https://doi.org/10.3389/fgene.2018.00236 Interpretive Summary: Bovine leukemia virus (BLV) produces leucosis, which can lead to lymphosarcoma in cattle. This virus causes economic losses to the cattle industry due to condemnation at slaughter. Molecules circulating in live cattle, known as transfer RNA fragments (tRFs), have been suggested to be regulators of gene expression in mammals. Establishing the difference in type and quantity of tRFs between healthy and diseased cattle will produce information needed to understand how genes are turned on or off, and how the animal’s immune system responds to diseases. The goal of this study was to establish if the expression of tRFs was different when compared between positive and negative Holstein cows to BLV. We identified three different tRFs that were down-regulated in positive, compared to negative cattle. These tRFs could be potentially involved in BLV disease progression and pathogenesis in cattle exposed to BLV.
Technical Abstract: Bovine leukemia virus (BLV) affects cattle health and productivity worldwide, causing abnormal immune function and immunosuppression. Transfer RNA fragments (tRFs) are known to be involved in inhibition of gene expression and have been associated with stress and immune response, tumor growth, and viral infection. The objective of this study was to identify tRFs associated with antibody response to BLV in Holstein cattle. Sera from 14 animals were collected to establish IgG reactivity to BLV by ELISA. Seven animals were seropositive (positive group) and 7 were seronegative (negative group) for BLV exposure. Leukocytes from each animal were collected and tRFs were extracted for sequencing. tRF5GlnCTG, tRF5GlnTTG, and tRF5HisGTG, were significantly different between seropositive and seronegative groups (P< 0.0067). In all cases the positive group had a lower number of normalized sequences for tRFs when compared to the negative group. Result suggests that tRF5s could potentially be used as biomarkers to establish exposure of cattle to BLV.