Abstract
Expression patterns of some small RNAs are regulated at developmental stages or in response to environmental changes. It is quite possible that viral infection alters the expression profile of small RNAs in host plants.
This time we analyzed small RNAs by sequencing small RNAs from Arabidopsis thaliana infected or uninfected with Tobacco mosaic virus.
About 80 % of the total small RNAs in infected plants matched to Arabidopsis genome sequences; about 10 % had the sequence of a part of the viral genome both of positive and negative strand. Of the Arabidopsis-specific sequences, the abundance of some microRNAs was higher in virus-infected plants than in uninfected plants. In addition, small RNAs matching to sequences of tRNA, rRNA and snRNA were found. Curiously, some small RNAs were found specifically in virus-infected plants. It is suggested that the analysis of virus-infected plants is offering us the chance of discovering novel small RNAs.
