Jaagsiekte Sheep Retrovirus Proviral Clone JSRV _JS7 , Derived from the JS7 Lung Tumor Cell Line, Induces Ovine Pulmonary Carcinoma and Is Integrated into the Surfactant Protein A Gene

Abstract

Ovine pulmonary carcinoma (OPC) is a contagious neoplasm of alveolar epithelial type II (ATII) or

Colostrum and milk can transmit jaagsiekte retrovirus to lambs

“…OPA is a lung tumour derived from type II pneumocytes and Clara cells caused by an exogenous betaretrovirus known as jaagsiekte sheep retrovirus (JSRV) DeMartini et al, 2001). Most natural cases appear in animals aged 2-4 years and only when the tumour volume becomes sufficient to interfere with lung function, clinical signs can be expected.…”

Oncogenic transformation by the jaagsiekte sheep retrovirus envelope protein

“…This paradox highlights, once again, the multistep nature of tumorigenesis by JSRV in sheep; more importantly, it suggests other mechanisms, such as insertional mutagenesis, might also play a role in JSRV oncogenesis. Several groups have investigated the possibility that JSRV provirus may have common integration sites in the sheep genomes, and obtained interesting but inconsistent results (DeMartini et al, 2001;Cousens et al, 2004;Philbey et al, 2006). Notably, one common integration site was recently identified on the sheep chromosome 16 (Cousens et al, 2004), and another clonal integration was observed in the receptor protein tyrosine phosphatase g genes of chromosome 19 (Philbey et al, 2006).…”

“…JSRV Env is a typical type-I transmembrane protein of approximately 620 amino acids in length before processing (York et al, 1992;Palmarini et al, 1999;DeMartini et al, 2001). The mature full-length Env is composed of surface (SU) and transmembrane (TM) subunits that are linked by disulfide bonds (Figure 1b).…”

“…This family also includes a closely related retrovirus of sheep and goats, enzootic nasal tumor virus (ENTV) . JSRV transforms peripheral lung epithelial cells leading to ovine pulmonary adenocarcinoma (OPA) (Palmarini et al, 1999;DeMartini et al, 2001), while ENTV transforms nasal epithelial cells resulting in enzootic nasal tumor (ENT) . OPA is a significant veterinary and economic problem in many countries, and in some countries such as Britain and South Africa, the incidence of OPA can be as high as 30% (Sharp and Angus, 1990).…”

“…Jaagsiekte sheep retrovirus (JSRV) is simple retrovirus encoding Gag, Pro, Pol, and Env proteins (York et al, 1992;Palmarini et al, 1999;DeMartini et al, 2001), and is now classified as an ovine betaretrovirus. This family also includes a closely related retrovirus of sheep and goats, enzootic nasal tumor virus (ENTV) .…”