Fig. 5.

Linker regions in Pin-II type PIs. a Classification of IRD sequences based on linker regions; heavy chain (H), light chain (L), RCL and linker regions are color-coded for sequences in (b) and (c). b Example of Pin-II type PI with H + L type IRDs. c Example of Pin-II type PI with overlapping H–L and L–H type IRDs. The images depicted in the figure are original images prepared by the authors