The 30-Kilodalton Gene Product of Tobacco Mosaic Virus Potentiates Virus Movement

TLDR

The proposed role of the 30‑kilodalton protein of tobacco mosaic virus is to facilitate cell‑to‑cell spread of the virus during infection. A chimeric gene encoding the 30‑kD protein was introduced into tobacco cells via Agrobacterium tumefaciens Ti plasmid transformation to directly define its function. Transgenic plants expressing the 30‑kD protein mRNA and protein complemented the temperature‑sensitive Lsl mutant and enhanced its cell‑to‑cell movement, conclusively demonstrating that the 30‑kD protein potentiates viral movement.

Abstract

The proposed role of the 30-kilodalton(kD) protein of tobacco mosaic virus is to facilitate cell-to-cell spread of the virus-during infection. To directly define the function of the protein, a chimeric gene containing a cloned complementary DNA of the 30-kD protein gene was introduced into tobacco cells via a Ti plasmid-mediated transformation system of Agrobacterium tumefaciens. Transgenic plants regenerated from transformed tobacco cells expressed the 30-kD protein messenger RNA and accumulated 30-kD protein. Seedlings expressing the 30-kD protein gene complemented the Lsl mutant of TMV, a mutant that is temperature-sensitive in cell-to-cell movement. In addition, enhanced movement of the Lsl virus at the permissive temperature was detected in seedlings that express the 30-kD protein gene. These results conclusively demonstrate that the 30-kD protein of tobacco mosaic virus potentiates the movement of the virus from cell to cell.