Comparative Structure and Function Analysis of the RIG-I-Like Receptors: RIG-I and MDA5

Brisse, Morgan; Ly, Hinh

RIG-I and MDA5 have been particularly implicated in their response to RNA genomes of viral defective interfering (DI) particles, as these defective viral genomes (DVGs) have originally been found to induce interferon signaling (150) . DI particles are produced by many viruses during infection, and while they are similar in many regards to standard viral particles, such as in appearance and composition, they cannot productively infect cells (200) . This is largely thought to be due to the presence of large and deleterious deletions in the DVG of DI particles (201) . Some DVG RNAs have also been noted to have "copy-back" motifs in which one end of the genome can base pair with an inverted copy at the opposite end of the genome, which may be due to stalled and aberrant replication (202, 203) .