Amino acid sequence alignment of Muscovy duck MDA5 protein with other MDA5 proteins. Accession numbers: human (accession numbers; NP_071451), mouse (NP_082111) and chicken (NP_001180567). The predicted motifs for CARD are indicated with gray bars on the alignment. The predicted motifs for DExD/H box RNA helicase domains are indicated by numbers (I-VI) and lines. Two predicted Zn2+-binding motifs and an RNA binding loop are indicated with black lines and a box. MDA5 sequences are shown for Muscovy duck (Md), human (Hu), mouse (Mo) and chicken (Ch).