Turnip yellow mosaic virus RNA is aminoacylated in vivo in Chinese cabbage leaves.

Turnip yellow mosaic virus (TYMV) contains a tRNA-like structure as an integral part of its genome. This structure is located at the extreme 3' end of the viral RNA and is the acceptor of valine after 3'-terminal adenylation. It is known that in vitro (with bacterial, yeast, or plant systems) and in vivo (upon microinjection into Xenopus laevis oocytes) a series of tRNA-specific enzymes can recognize this structure in the viral RNA. We report that TYMV RNA is valylated and consequently adenylated in vivo in its natural host, Chinese cabbage leaves. This suggests that the acylated form of the viral RNA could play an important role in the life-cycle of the virus.