A quail long-term cell culture transformed by a chimeric jun oncogene

Area of Science:

• Molecular Biology
• Cell Biology
• Virology

Background:

• Jun proteins are key regulators of cell proliferation and differentiation.
• Viral jun oncogenes are known to induce rapid cell transformation.
• Understanding the mechanisms of Jun-mediated transformation is crucial for cancer research.

Purpose of the Study:

• To develop a novel chimeric Jun construct for efficient cell transformation.
• To establish a continuous cell line expressing the chimeric Jun construct for mechanistic studies.
• To investigate the molecular basis of Jun-induced cell transformation.

Main Methods:

• Cloning of a chimeric construct (VCD) comprising viral jun, chicken c-jun, and chicken junD into the RCAS retroviral vector.
• Transfection of primary quail embryo fibroblasts with RCAS-VCD and subsequent isolation of a transformed cell line (VCD).
• Characterization of VCD cells using focus formation assays, agar colony formation, Southern, Northern, and Western blot analyses.

Main Results:

• RCAS-VCD exhibited higher focus-forming potential than RCAS-VJ-1 (viral jun).
• A stable, long-term VCD cell line was established, continuously producing transforming virus at high titers (10^5 FFU/ml).
• VCD cells demonstrated anchorage-independent growth and correct expression of the chimeric Jun(VCD) protein without detectable genomic rearrangements.

Conclusions:

• The chimeric Jun(VCD) construct efficiently transforms quail fibroblasts, leading to a stable, virus-producing cell line.
• The VCD cell line serves as a valuable and homogeneous model for studying Jun-induced cell transformation.
• This system facilitates the identification of direct and indirect targets of Jun protein function in cellular transformation.