Chimeric provirus of bovine leukemia virus/ SMAD family member 3 in cattle with enzootic bovine leukosis

Abstract

Abstract Bovine leukemia virus (BLV) is a member of the family Retroviridae and causes enzootic bovine leukemia (EBL). However, the association between BLV infection and EBL development remains unclear. In this study, we identified a BLV/SMAD3chimeric provirus within CC2D2A intron 30 in monoclonal expanded malignant cells from an EBL cow. The chimeric provirus harbored a SMAD3spliced sequence composed of exons 3–9 encoding the short isoform protein, and the BLV-SMAD3chimeric transcript was detectable in EBL cattle. This is the first report of a BLV chimeric provirus that might be involved in EBL tumorigenesis.