A pathogenic non coding RNA that replicates and accumulates in chloroplasts traffics to this organelle through a nuclear-dependent step

Viroids belonging to the family Avsunviroidae are the only functional RNAs known to traffic selectively into chloroplasts. Subcellular targeting is a critical step in guaranteeing their access to the machineries involved in their replication. However, the host mechanisms exploited by these non coding pathogenic RNAs to be selectively imported into chloroplasts are poorly understood. Recently, we provide evidence supporting the idea that the Avsunviroidae have evolved to subvert a signaling mechanism between the nucleus and chloroplasts to regulate their differential compartmentalization into the chloroplast of infected cells. Here, we discuss our model and previous observations that provide biological relevance to our hypothesis.