Structure-based mechanism of RyR channel operation by calcium and magnesium ions
Fig 8
Divalent ion-related allosteric networks of the ryanodine receptor.
The scheme integrates the intra-monomeric (white background) and the inter-monomeric pathways (gray background). Note that both pathway types are present in each monomer. Red – the activation network. Green – the inhibition network. Black – the shared activation and inhibition sub-paths. The branches are labeled in correspondence to Tabs 3–5 - 5. ACT – the activation site; INH – the inhibition site; CTD – the C-terminal domain; CFF – the caffeine binding site; S23 – the S23 loop; U, U* - the U-motifs; ATP – the ATP binding site; S45, S45* - the S45 linkers; S6/S6* - the S6 helices; GATE - the gating site. The spatial arrangement of the pathways of two example structures (the RyR1 inactivated structure 7tdg and the RyR2 open structure 7ua9) is shown in S2 Fig.