FIGURE 1.

The putative S4-S5 linker in RyR1. A, schematic drawing of the transmembrane topology of the RyR1 channel based on the model according to Du et al. (15). The cylinders S1–S6 represent the transmembrane segments that correspond to those originally proposed in the Zorzato model (M5–M10) (34). The putative S4-S5 linker is highlighted by the boldface line. B, amino acid sequence and the helix probability of the S4-S5 linker in RyR1. The helix probability was predicted by the continuum secondary structure predictor (35, 36). The helix probability is high in the N-terminal half of the S4-S5 linker.