Competition between Coiled-Coil Structures and the Impact on Myosin-10 Bundle Selection.
Coiled-coil fusions are a useful approach to enforce dimerization in protein engineering. However, the final structures of coiled-coil fusion proteins have received relatively little attention. Here, we determine the structural outcome of adjacent parallel and antiparallel coiled coils. The targets are coiled coils that stabilize myosin-10 in single-molecule biophysical studies. We reveal the solution structure of a short, antiparallel, myosin-10 coiled-coil fused to the parallel GCN4-p1 coiled coil. Surprisingly, this structure is a continuous, antiparallel coiled coil where GCN4-p1 pairs with myosin-10 rather than itself. We also show that longer myosin-10 segments in these parallel/antiparallel fusions are dynamic and do not fold cooperatively. Our data resolve conflicting results on myosin-10 selection of actin filament bundles, demonstrating the importance of understanding coiled-coil orientation and stability.
Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois.
Kevin C
KC
Vavra
Minnesota NMR Center, University of Minnesota, Minneapolis, Minnesota.
Youlin
Y
Xia
Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois. Electronic address: rrock@uchicago.edu.
Ronald S
RS
Rock
D008841:Actin Cytoskeleton / Q000378:metabolism; D050976:Basic-Leucine Zipper Transcription Factors / Q000378:metabolism*; D002942:Circular Dichroism; D004926:Escherichia coli; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D009218:Myosins / Q000378:metabolism*; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D017510:Protein Folding; D055550:Protein Stability; D053838:Scattering, Small Angle; D014961:X-Ray Diffraction
D050976:Basic-Leucine Zipper Transcription Factors; D009218:Myosins