Abstract
It is known in plants and C. elegans that siRNA is produced from the region outside of the genes dsRNA is originally targeted by RNA dependent RNA polymerase resulting in spreading of RNAi to nonconserved regions. If this "spreading of RNAi" occurs it would be difficult to specifically suppress function of a member of a gene family by RNAi.
In most of the OsRac gene family coding regions of the genes are highly conserved, however their 3' UTRs are less conserved. Therefore, we designed RNAi constructs from which dsRNA of 3' UTR regions are produced from 7 different genes. The each of 7 members of the OsRac gene family was specifically suppressed by the respective RNAi construct in transgenic rice.
These results suggested that RNAi by dsRNA for 3' UTR is a useful method to identify functions of individual members of a gene family.
