Authors : Hao Chen, Yi-Xin Wang, Peng Zhao, Jian-Liang Li and Zhi-Zhong Cui
Abstract: To explore the reason of acute fibrosarcoma formation in chickens, researchers detected the existence of viral antigens in the cytoplasm of infected CEFs by monoclonal antibody against ALV-J and rabbit polyclonal antibody against oncogene-fps protein. PCR amplified the whole genome sequence of the replication-competent ALV-J (SD1005), alignment of the complete sequence demonstrated that it has no remarkable mutation in the genome and appears not to be the real pathogen inducing the acute tumorigensis. Additionally, we obtained several genome sequences associated with ALV-J (Fu-J1-6) which is defective with parts of gag, pol and env genes replaced by a sequence of fps gene. The sequences of Fu-Js revealed that their genomes are closely related to that of SD1005 and probably derived from it in accordance with the high homology (>99%) in env gene between them. Notably, compared with homologous region of Fujinami and PRCII, the obtained v-fps genes in the study have two deletion mutations at both ends with the major diversity at the 3'-fps end, especially. So, researchers infer that it seems to be unstable for junction site in the process of recombination between c-fps oncogene and retrovirus ALV, a majority of variable individuals at gene level (quasispecies) will generate, one strain of which has biological activity at least. Obviously, the induction of acute fibrosarcomas in the experiment occurs through mechanisms involving the direct activation of viral oncogene v-fps in Fu-Js rather than insertional activation of cellular oncogene c-fps, revealing that the tumorigenesis induced by ALV-J is probable to involve fps oncogene besides for the myc oncogene. This is the first report on acute fibrosarcomas caused by ALV-J containing v-fps oncogene since the identification of this virus in 1988.
Hao Chen, Yi-Xin Wang, Peng Zhao, Jian-Liang Li and Zhi-Zhong Cui, 2012. Acute Fibrosarcomas Caused by Avian Leukosis Virus Subgroup J Associated with v-fps Oncogene. Journal of Animal and Veterinary Advances, 11: 2910-2916.