Sequence comparison between DIRs from Forsythia intermedia , Thuja plicata , Arabidopsis thaliana and Isatis indigotica.Residues conserved in all of the sequences are indicated in black. Sequence conservation between A. thaliana and I. indigotica is highlighted in blue. Conservation between T. plicata and F. intermedia is highlighted in green. Conservation between AtDIR6, IiDIR2, IiDIR3 and IiDIR4 is highlighted in red. Conservation between AtDIR5 and IiDIR1 is highlighted in yellow. Conservation between AtDIR6 and IiDIR2 is highlighted in gray. Predicted N-terminus signal peptides are shown in italics with underline.