Fig. 4.

RAC1/3 and CDC42 phosphorylate IRF3. (A) HEK293 cells were co-transfected with FLAG-IRF3 and individual Rho GTPases. 24 h post transfection, the migration shift of IRF3 was determined by Phos-tag gel electrophoresis. Red, strong phosphorylation; blue, weak phosphorylation. (B) Phylogenetic comparison between Rho family proteins. The sequences were multiply aligned by using ClustalW. Horizontal distance represents the proportion of amino acid difference and the branch values denote the bootstrap confidence values. (C) Alignment of amino acid sequences for Rho GTPases that positively regulate IRF3 phosphorylation. Common domain structure of Rho GTPases is shown above. (D) Protein sequence identity among Rho GTPases that increase phosphorylation of IRF3. Identity, percentage of identical residues; similarities, percentage of similar functional residues.