Fig. 2: Structural features of each domain.
a Topological diagram and overall structure showing one SIDT2 protomer. The CTD is invisible in the structure, reflecting its flexibility. b BRD1 contains eleven β-sheet folds as two lamellar structures facing each other. One disulfide bond is formed between C117 of BRD1 and C207 of BRD2, and five glycosylation sites are observed in BRD1. c BRD2 contains eight β-sheet folded into two lamellar structures facing each other. One glycosylation site and one disulfide bond are present. d The TMD contains eleven transmembrane helices containing a putative Zn2+-binding site formed by three histidine residues, one aspartate residue, and one serine residue. The putative Zn2+ is located approximately 6 Å from the extracellular/luminal surface of the membrane. Two pairs of disulfide bonds are formed in the extracellular/luminal loops. Except for TM2, the TMs are arranged counterclockwise in an orderly manner from the extracellular/luminal view. loop 2–3 indicates the loop between the TM2 and TM3, loop 10-11 indicates that the loop between the TM10 and TM11.
