Proteasomal inhibitor MG132 (SigmaeAldrich) was dissolved in
DMSO at the concentration of 5 mM/mL.
The shDDX21 against DDX21 and shNC containing the scrambled
sequence as a negative control were purchased from GeneChem.
The pCDNA3-DDX21 (pD21) was a gift from Dr. Ariumi to
express DDX21 in cells. To express DENV non-structural proteins
NS2B and NS3 in cells, the full-length DENV-2 genome containing
plasmid FL-D2 [17] was used as the template to amplify NS2B and
NS3 sequences, and then the NS2B and NS3 genes were cloned into
vector pCI-neo.