The Mutation Of P53 Gene And Role In ALV-J Infection And Pathogenesis

J subgroup avian leucosis is a kind of avian neoplastic disease caused by J subgroup avian leucosis virus(ALV-J).Since the first isolation of ALV-J from chickens in 1988,ALV-J has become widespread in chickens around the world.In Europe and America,ALV-J was eradicated from chickens through monitoring and purifying measures.However,ALV-J has been pop?Lar among chickens since it was introduced to chickens in China in 1999.Especially since 2008,ALV-J has been used in some of our country.Chickens are characterized by hemangioma and tumor formation in various internal organs.As avian leukosis is a source of vertical transmission.Sexual diseases,some kinds of poultry farms closed down due to the occurrence of the disease.ALV-J has caused serious losses to the poultry industry in China.It has received extensive attention from the government and the chicken industry and has conducted extensive research in the epidemiology,etiology,pathology,and monitoring and purification of the disease.In our previous study we found that p53 gene mutation and overexpression are important events in the pathogenesis of the disease.The p53 gene was discovered as an oncogene in 1979.With the development of the study,the tumor suppressor effect of p53 gene has been recognized.There are mutations in the p53 gene in various tumor diseases.The p53 gene has gradually attracted attention.And become a hot topic of research.Later,people also found that p53 protein has antiviral function,and the appearance of p53 antigen and antibodies in the blood has become a tumor marker.This study intends to investigate the role of mutant p53 overexpression in the expression of other tumor-associated genes to explore the role of mutation and overexpression of p53 gene in the development of subgroup J leukemia;to compare the overexpression of wild-type and mutant p53 genes with ALV-J.Effect of in vitro replication;Study of the relationship between changes of blood p53 antibody and antigen levels and the pathogenicity of ALV-J infection,providing new ideas for early warning and prevention of ALV-J infection.In this study,mutant p53 gene recombinant plasmid was transfected into CEF cells,and the effect of mRNA expression of tumor-associated genes was detected by fluorescence quantitative PCR.It was found that overexpression of mutant p53 protein can cause high expression of C-myb and C-myc oncogene and tumor suppression.Low expression of gene p16.The wild-type p53 recombinant plasmid was transfected into CEF cells and then infected with ALV-J.The cells were collected at 12 h,24h,and 36 h,respectively,and the virus copy number was detected by absolute fluorescence quantitative PCR.It was found that overexpression of wild-type p53 protein can effectively inhibit the virus.Replication,but no significant effect on mutants.After ALV-J was infected with SPF chickens,serum and whole blood were collected reg?Larly.Serum p53 protein and antibody levels were detected by ELISA.Whole blood was used to extract RNA to detect p53 gene mutation.The results showed that both p53 protein and antibody increased after 5th week,and significantly higher than the control group.The p53 gene detection found that the mutation rate reached 70%.The above results indicate that overexpression of mutant p53 can cause high expression of oncogene C-myb and C-myc and low expression of tumor suppressor gene p16,which may be an important mechanism for mutant p53 to exert tumorigenicity.Overexpression of wild-type p53 can inhibit the in vitro replication of ALV-J,providing a new idea for the prevention and control of ALV-J.Detection of p53 antigen and antibody levels can be used as a marker of early screening for ALV-J.