This document describes a study that used virus-induced gene silencing (VIGS) to investigate the role of the hexose transporter gene LeHT1 in tomato resistance to Tomato yellow leaf curl virus (TYLCV). The gene was silenced in resistant and susceptible tomato lines. Silencing LeHT1 compromised resistance in resistant plants, allowing higher virus accumulation. Silenced resistant plants also developed necrosis and oxidative burst symptoms in response to TYLCV and other viruses. The results suggest LeHT1 plays a role in resistance by limiting virus entry/movement in cells and that silencing uncovered a secondary resistance mechanism involving programmed cell death.