Location: Animal Health GenomicsTitle: First complete genome sequence of a genotype A2, subgroup 4 small ruminant lentivirus
Submitted to: Microbiology Resource Announcements
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/26/2018
Publication Date: 11/15/2018
Citation: Workman, A.M., Clawson, M.L., Heaton, M.P., Dickey, A.M. 2018. First complete genome sequence of a genotype A2, subgroup 4 small ruminant lentivirus. MICROBIOLOGY RESOURCE ANNOUNCEMENTS. 7(19):e01337-18. https://doi.org/10.1128/MRA.01337-18.
Interpretive Summary: Small ruminant lentiviruses (SRLV) are a heterogeneous group of viruses that infect sheep and goats causing incurable, progressive diseases that greatly impact animal welfare and productivity. Viral tropism and host susceptibility to the different SRLV strains are influenced by both host and virus genotypes. In sheep, genetic variation in the transmembrane protein 154 (TMEM154) gene is associated with susceptibility to SRLV infection. On the pathogen side, two distinct SRLV subgroups evolved to infect sheep in association with the host TMEM154 diplotype. While the biological function of TMEM154 and the role it plays in SRLV infection remains unknown, their apparent co-evolution suggested TMEM154 plays an important role in the virus lifecycle. Thus, it was hypothesized that sheep lacking a functional copy of TMEM154 may be resistant to SRLV infection. However, a novel SRLV A2 subgroup (subgroup 4) was recently identified that infected two sheep lacking functional TMEM154 as well as other sheep with various TMEM154 diplotypes. In this study, we report the first complete viral genome sequence from a SRLV infecting a U.S. ewe with two copies of a TMEM154 frameshift mutation predicted to abolish protein function. This genome represents the first complete genome for a virus belonging to SRLV genotype A2, subgroup 4 and can be used to study SRLV evolution.
Technical Abstract: Genetic variation in the ovine TMEM154 gene associates with susceptibility to small ruminant lentivirus (SRLV) infection. We report here the first complete genome sequence for a genotype A2, subgroup 4 SRLV isolated from a Hampshire ewe with two copies of a TMEM154 frameshift mutation predicted to abolish protein function.