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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, RESULTS. Meshes: Animals, Chickens, Chromosomes, Artificial, Bacterial, Genetic Vectors, Male, Mardivirus, Marek Disease, Oncogenic Viruses, RNA, Messenger, Sequence Deletion, Virulence, Virus Replication.
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Does deletion of 1.8-kb mRNA of Marek 's disease virus decrease its replication ability but not oncogenicity? Context: The 1.8-kb mRNA was reported as one of the oncogenesis-related genes of Marek's disease virus (MDV). In this study, the bacterial artificial chromosome (BAC) clone of a MDV field strain GX0101 was used as the platform to generate mutant MDV to examine the functional roles of 1.8-kb mRNA. Based on the BAC clone of GX0101, the 1.8-kb mRNA deletion mutant GX0101Δ(A+C) was constructed. The present experiments indicated that GX0101Δ(A+C) retained a low level of oncogenicity, and it showed a decreased replication capacity in vitro and in vivo when compared with its parent virus, GX0101. Further studies in vitro demonstrated that deletion of 1.8-kb mRNA significantly decreased the transcriptional activity of the bi-directional promoter between 1.8-kb mRNA and pp38 genes of MDV.
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These results suggested that the 1.8-kb mRNA did not directly influence the oncogenesis but related to the replication ability of MDV. Final Decision: yes