We examined the fine structure of the type I signal-anchor sequence of synaptotagmin II, which has a 60-residue N-terminal domain followed by a hydrophobic region (H-region), focusing on the hinge region between the N-terminal and the H-regions. It was found that the charged or highly polar residues support the translocation of the N-terminal domain through the endoplasmic reticulum membrane at specific positions in the hinge. The residue requirement correlated with the turn propensity scale for transmembranes. It is suggested that a certain conformation, likely helical hairpin, in the hinge is critical for N-terminal domain translocation.