An Arabidopsis thaliana protein interacts with a movement protein of Turnip crinkle virus in yeast cells and in vitro

Plant virus movement proteins bind host components to promote virus movemen t from initially infected cells to neighbouring cells. In this study, cDNA clones encoding p8 and p9, two small proteins required for the movement of Turnip crinkle virus, were used as 'bait' in a yeast two-hybrid system to s creen an Arabidopsis thaliana cDNA library for interactive proteins. One A. thaliana clone was identified that encodes a protein, designated Atp8, whi ch interacted with p8 in yeast cells and in vitro. The apparent full-length of Atp8 mRNA was sequenced and shown to encode a protein with two possible transmembrane helices, several potential phosphorylation sites and two 'RG D' sequences.