Which of the following proteins stabilizes actin filaments by binding along their length?
Skeletal muscle thin filaments extend from Z disc to near M line, length precisely regulated 1.0 micrometer in cardiac, 1.1 to 1.3 in skeletal for optimal overlap with thick filaments for force generation. Nebulin, 600 to 900 kilodalton protein encoded by NEB gene, composed of 185 tandem nebulin repeats of 35 amino acids each predicted to contact single actin monomer plus C terminal SH3 domain anchoring at Z disc via interactions with CapZ, titin Z repeats and desmin intermediate filaments. By spanning entire thin filament, nebulin acts as molecular ruler templating polymerization length durin
Ref: Alberts et al., Molecular Biology of the Cell, 7th ed., Chapter 16: Nebulin and Thin Filament Stabilization.
