Size dictates mechanical properties for protein fibers self-assembled by the Drosophila hox transcription factor ultrabithorax.
The development of protein-based materials with diverse mechanical properties will facilitate the realization of a broad range of potential applications. The recombinant Drosophila melanogaster transcription factor Ultrabithorax self-assembles under mild conditions in aqueous buffers into extremely extensible materials. By controlling fiber diameter, both the mechanism of extension and the magnitude of the mechanical properties can be varied. Narrow Ultrabithorax fibers (diameter <10 μm) extend elastically, whereas the predominantly plastic deformation of wide fibers (diameter >15 μm) reflects the increase in breaking strain with increasing diameter, apparently due to a change in structure. The breaking stress/strain of the widest fibers resembles that of natural elastin. Intermediate fibers display mixed properties. Fiber bundles retain the mechanical properties of individual fibers but can withstand much larger forces. Controlling fiber size and generating fiber superstructures is a facile way to manipulate the mechanical characteristics of protein fibers and rationally engineer macroscale protein-based materials with desirable properties.
Departments of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005, United States.
Zhao
Z
Huang
Yang
Y
Lu
Ravish
R
Majithia
Jaimin
J
Shah
Kenith
K
Meissner
Kathleen S
KS
Matthews
Sarah E
SE
Bondos
Jun
J
Lou
D000818:Animals; D001672:Biocompatible Materials; D029721:Drosophila Proteins / Q000502:physiology*; D004331:Drosophila melanogaster; D018398:Homeodomain Proteins / Q000502:physiology*; D008422:Materials Testing; D055595:Mechanical Phenomena; D011506:Proteins / Q000648:ultrastructure*; D014157:Transcription Factors / Q000502:physiology*
D001672:Biocompatible Materials; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; D011506:Proteins; D014157:Transcription Factors; C066177:Ubx protein, Drosophila