Fig. 2
From: Network topology of NaV1.7 mutations in sodium channel-related painful disorders
NaV1.7 structure and inter-atomic network features. a View of the sodium channel α-subunit from the intracellular side of the membrane NaV1.7 is folded into four repeated domains (DI–DIV); helices S1–S4 comprise the voltage-sensing domain (VSD); helices S5–S6 and their intracellular linker comprise the pore domain (PD). b Intramembrane view of the folded model of NaV1.7. c The graph shows the topology of the mutations found in patients with inherited erythromelalgia (IEM; red), paroxysmal extreme pain disorder (PEPD; green), small-fibre neuropathy (SFN; purple) and the amino acid substitution with no biophysical abnormalities (nABN) and homologous SNPs (light blue). Nodes represent the residues and edges of the interatomic bonds. Red and black edges represent high (red) or low (grey) edge betweenness centrality (EB ct ) values, respectively. Edge thickness are proportional to EB ct and reveal that a high number of shortest paths pass through few edges. *This mutation associates with clinical features of IEM and SFN. ǂThis mutation causes in vitro biophysics changes and in vivo symptoms common both to IEM and PEPD. The NaV1.7 amino acid network were visualized using Cytoscape’s Organic layout, which is a force-directed layout algorithm similar to the Fruchterman-Reingold approach