Which of the following proteins is a major crosslinker of actin filaments in the cytoskeleton?
Actin filaments crosslinked into distinct architectures produce diverse mechanical properties. Short crosslinkers like fimbrin fascin 8 to 12 nanometer spacing generate tight parallel bundles in microvilli and filopodia for protrusion, long crosslinkers alpha actinin filamin 30 to 40 nanometer create loose networks and antiparallel bundles allowing myosin II insertion for contraction. Alpha actinin antiparallel homodimer 35 nanometer rod contains N terminal actin binding domain with paired calponin homology CH1 CH2, four spectrin repeats dimerization core and C terminal calmodulin like EF hand
Ref: Alberts et al., Molecular Biology of the Cell, 7th ed., Chapter 16: Alpha-Actinin Crosslinking Actin Filaments.
