Driving forces of continuing evolution of rotaviruses

Figure 1 Schematic structure of rotaviruses. Rotaviruses are a non-enveloped RNA virus that has 11 segments of double-stranded RNA (dsRNA) covered by three layers of capsid proteins. The inner layer consists of VP1 and VP2 proteins, the middle layer consists of VP6 protein, while the outer layer consists of VP4 and VP7 proteins.

Figure 2 Reassortment mechanism of rotaviruses group A (RVA). A: Diagrammatic representation of the emergence of a novel reassortant strain with genes derived from two parental strains; B: Reassortment in RVA begins with the synthesis of positive-sense RNA. A total of newly-synthesized 11 positive segments of RNA will form a complex of supramolecular structures and be immediately assembled by virion particles that grow through the encapsidation process. The polymerase enzyme then converts positive RNA into dsRNA shortly after the encapsidation process.

Figure 3 Cartoon representation of Rotavirus strategy to evade the host innate immune system. OAS: Oligoadenylate synthase; β-TrCP: Beta-transducin repeats-containing proteins; IRF: Interferon regulatory factor; STAT: Signal transducer and activator of transcription; PABP: Poly(A) binding protein; ISRE: Interferon-stimulated response element; eIF4G: Eukaryotic translation initiation factor 4G.