RIG-I Self-Oligomerization Is Either Dispensable or Very Transient for Signal Transduction
Figure 5
Lack of RNA induced RIG-I oligomerization in cellula as detected using PCA.
(A) Ability of RIG-I/glu/gcn4 constructs to self-associate in the absence or presence of Poly(I:C) determined by PCA. Luciferase activity was measured 18 hours after transfection or not with Poly(I:C) in 293T cells transfected one day before with RIG-I/glu1/2/gcn4 constructs. (A, inset) Expression of chimeric RIG-I/glu1/2 constructs tagged with Cl25 or HA peptides in Huh7.5 cells two days after transfection as detected by western blot (note that the third sample (Glu1-RIG-I-GCN4 was overloaded, hence the overexposure of this protein and GAPDH). (B) Ability of RIG-I/glu/gcn4 chimeric proteins (left panel) and glu-gcn4 protein (right panel) for self-binding determined by western blot 24 hours post-transfection of 293T cells with glu1 or glu2 constructs alone or in combination. Lysates were separated without prior heat denaturation on SDS-PAGE before western blot analysis.