Stable expression of a Norwalk virus RNA replicon in a human hepatoma cell line.

Norwalk virus (NV) is a prototype strain of the genus Norovirus in the family Caliciviridae. The human noroviruses have emerged as major agents of acute gastroenteritis in all age groups, but there are no vaccines or antiviral agents partly due to the absence of a cell culture system. We report the generation of cells expressing self-replicating NV RNA (NV replicon) following transfection of NV RNA bearing an engineered neomycin resistance gene into cell lines of human (Huh-7) or hamster (BHK21) origin.

Norwalk virus N-terminal nonstructural protein is associated with disassembly of the Golgi complex in transfected cells.

Norwalk virus is the prototype strain for members of the genus Norovirus in the family Caliciviridae, which are associated with epidemic gastroenteritis in humans. The nonstructural protein encoded in the N-terminal region of the first open reading frame (ORF1) of the Norwalk virus genome is analogous in gene order to proteins 2A and 2B of the picornaviruses; the latter is known for its membrane-associated activities. Confocal microscopy imaging of cells transfected with a vector plasmid that provided expression of the entire Norwalk virus N-terminal protein (amino acids 1 to 398 of the ORF1 polyprotein) showed colocalization of this protein with cellular proteins of the Golgi apparatus.