Spatial Distribution of Acidic Chitinases and Their Messenger RNAs in Tobacco Plants Infected with Cherry Leaf Roll Virus

Abstract

Cherry leaf roll virus (CLRV) infection in Nicotiana tabacum cv. Xanthi nc plants induces the expression of, among others, basic and acidic chitinases at 3 d.p.i. (days postinoculation) and 8 d.p.i. in inoculated and uninoculated, systemically infected leaves, respectively. The spatial distribution of the acidictobacco chitinases (PR-P and PR-Q) mRNAs in CLRV-infected tobacco leaves has been studied by tissue printing and Northern (RNA) blot analysis. The mRNA was preferentially detected in and around the concentric necrotic rings caused by the viral infection. In addition, the accumulation pattern of the proteins was very similar although a basal signal was detected in nonsymptomatic tissue in uninoculated, systemically infected leaves. These results indicate a positive association of acidic chitinase gene expression with the necrotic tissue, where the virus is mainly localized, in the CLRV-tobacco interaction.