Vero cells injected with adenovirus type 2 mRNA produce authentic viral polypeptide patterns: early mRNA promotes growth of adenovirus-associated virus.

Adenovirus type 2 mRNAs were injected via glass capillaries into Vero cells, a line of African green monkey kidney cells permissive for adenovirus growth. Polypeptides synthesized after injection were labeled with 35S-labeled amino acids, precipitated with antiviral sera, and analyzed by polyacrylamide gel electrophoresis. Both early and late viral mRNAs give rise to authentic polypeptides. The in vivo translation of mRNAs can be measured as late as 24 hr after injection. The ability to analyze the protein products of microinjected mRNAs directly should greatly extend the applications of the procedure. Vero cells injected with early mRNA from adenovirus type 2 support the growth of adenovirus-associated virus, a defective virus that is dependent on adenovirus helper functions. This result demonstrates that a measurable biological activity, the ability to overcome the defectiveness of adenovirus-associated virus, resides in early adenovirus mRNA.