Abstract
The molecular basis has been proposed as a gene-for-gene system, in which plants recognize the pathogen molecule by specified protein(s), this being called the R factor. However, mechanisms of interaction between proteins from the host and the pathogen are not completely understood. Here, we analyzed the mode of interaction between the N factor, a tobacco R factor, and the helicase domain (p50) of tobacco mosaic virus (TMV). To this end, domain dissected proteins were prepared and subjected to Agroinfiltration into intact leaves, followed by yeast two hybrid and pull-down assays. The results pointed to three novel features. First, the N factor was found to directly bind to the p50 of TMV, second, ATP was prerequisite for this interaction, with formation of an ATP/N factor complex, and third, the N factor was shown to possess ATPase activity, which is enhanced by the p50.
