Question: A multipass transmembrane protein is shown schematically below. The boxes represent membrane-spanning segments and the arrow represents a site for cleavage of the signal sequence. Given this diagram, sketch how the protein will be arranged across:
1) the membrane of the ER,
2) the membrane of a transport vesicle,
3) after it gets delivered to the plasma membrane
Indicate clearly the N- and C-termini relative to the cytosol and the lumen of the ER, and label each box as a start-transfer or stop-transfer signal. Indicate on your drawings the cytosolic face, the ER lumen and the extracellular space.