Gene C2 of the monopartite geminivirus Tomato yellow leaf curl virus-Chinaencodes a pathogenicity determinant that is localized in the nucleus

Expression of the Tomato yellow leaf curl virus-China (TYLCV-C) C2 protein and green fluorescent protein (GFP) fused to the C2 protein (C2-GFP) in Nic otiana benthamiana from a Potato virus X (PVX) vector induced necrotic ring spots on inoculated leaves as well as necrotic vein banding and severe necr osis on systemically infected leaves. The localization of GFP fluorescence in plant cells infected with PVX/C2-GFP and in insect cells transfected wit h Baculovirus expressing C2-GFP indicates that the TYLCV-C C2 protein is ca pable of shuttling GFP into plant and insect cell nuclei. Our data demonstr ate that the TYLCV-C C2 protein may contribute to viral pathogenicity in pl anta and is nuclear localized.