Hernandez-Guzman, J.; Arias, C.; Lopez, S.; Sandoval-Jaime, C.

Rotavirus infection is a leading cause of gastroenteritis in children worldwide, the genome of this virus is composed of eleven segments of dsRNA packed in a triple-layered protein capsid. Here, we investigated the role of nucleolin, a protein with diverse RNA-binding domains, on rotavirus infection. Knocking down the expression of nucleolin in MA104 cells by RNA interference resulted in a remarkable 5-fold increase in the production of infectious rhesus rotavirus (RRV) progeny, accompanied by an elevated synthesis of viral mRNA and genome copies. Further analysis unveiled an interaction between rotavirus segment 10 (S10) and nucleolin, potentially mediated by G-quadruplex domains on the viral genome. To determine whether the nucleolin-RNA interaction regulates RRV replication, MA104 cells were transfected with AGRO100, a compound that forms G4 structures and selectively inhibits nucleolin-RNA interactions by blocking the RNA binding domains. Under these conditions, viral production increased by 1.54-fold, indicating the inhibitory role of nucleolin on the yield of infectious viral particles. Furthermore, G4 sequences were identified in all eleven RRV dsRNA segments, and transfection of oligonucleotides representing G4 sequences in RRV S10 induced a significant increase in viral production. These findings show that rotavirus replication is negatively regulated by nucleolin through direct interaction with the viral RNAs by sequences forming G4 structures.