Fig. 3.

Multiple Ras proteins activate IRF3. (A) HEK293 cells were co-transfected with FLAG-IRF3 and individual Ras 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 Ras family proteins. The sequences were aligned 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 Ras GTPases that positively regulate IRF3 phosphorylation. Common domain structure of Ras GTPases is shown above. (D) Protein sequence identity among Ras GTPases that increase phosphorylation of IRF3. Identity, percentage of identical residues; similarities, percentage of similar functional residues.