2010 Rustbelt RNA Meeting
RRM
Poster abstracts
Abstract:
How an RNA itself directly regulates its trafficking between cells remains poorly understood, though the importance of inter-cellular RNA trafficking has been well-established based on the studies on both endogenous and infectious RNAs in plants. Viroids, small but highly structured non-coding RNAs, are excellent models to investigate the molecular mechanism of RNA trafficking. Using Potato spindle tuber viroid (PSTVd) infection of Nicotiana benthamiana as the experimental system, we demonstrated that various RNA loop structures, consisting of non-Watson-Crick base pairs, were essential for PSTVd systemic trafficking. Here, we present our analyses on the role of loop 6, a conserved motif comprising six nucleotides, in regulating inter-cellular RNA trafficking. The tertiary structural model of loop 6 was inferred by comparisons with the X-ray crystal structures of similar motifs in other RNAs. Extensive mutational analyses supported the structural model. Cellular analyses revealed that the maintenance of the tertiary structure of loop 6 is essential for PSTVd to traffic between specific cell types. Our findings support the hypothesis that unique RNA structural motifs mediate trafficking across distinct cellular layers. Furthermore, our approaches should be useful in characterizing the structure-function relationships for other RNA motifs.
Keywords: Viroid, RNA trafficking, RNA structural motif