Figure 3.
The overall structure of SERCA (Sarco/endoplasmic reticulum Ca2+ ATPase) pump. (A) The topology of SERCA showing 10 transmembrane segments (TMS (transmembrane segment) 11 is found only in SERCA2b), with a large cytoplasmic N-terminal, large cytoplasmic loops, and a luminal C-terminal. (B) Overall 3D-architecture of SERCA transporter in the E2-state complexed with a Thapsigargin derivative Boc-(phi)Tg (Protein Data Bank [PDB] code 3NAN). Cytoplasmic and luminal loops are shown in gray, TMSs are shown in blue, and Tg inhibitor is shown in red. CYT = cytoplasm; ER lumen = endoplasmic reticulum lumen.