Figure 1

Nebulin and β-tropomyosin mutations studied. (A) The nebulin protein structure and the location of the mutations. The upper part of the figure shows a schematic presentation of the nebulin protein structure and its known protein interaction partners. The lower part of the figure shows a detailed view of the super repeats included in the study (S9, S14, S18, and S22), and the location of the mutations (arrows) and tropomyosin-binding sites (X) in the super repeats. (B) Purified GST (glutathione-S-transferase)-nebulin and tropomyosin. GST-nebulin domains were produced in the Escherichia coli strain BL21 (upper panel), and the α-tropomyosins (Tm3) and β-tropomyosins (Tm2) in insect cells (lower panel). The proteins were purified, run in a SDS-PAGE gel, and stained with Coomassie Blue. The β-tropomyosin mutations p.K49del and p.E139del cause altered protein conformation and thus slower migration in the SDS-PAGE gel [35]. Nomenclature of the mutations in relation to other figures: p.Glu2431Lys = ex54m, p.Arg2478_Asp2512del = ex55del, p.Val3924_Asn3929del = ex78m, p.Ser6366Ile = ex122m, p.Thr7382Pro = ex151m. Abbreviations: Tmod, tropomodulin; M1-M8, M163-M176, M177-M185 simple repeats; S1R1-S1R7, S22R1-S22R7, super repeats of seven simple repeats; Ser, Serine-rich domain, SH3, Src homology domain.