Complex biological fibers might just form because the protein 'bricks' are slightly wonky and don't fit together perfectly.
April 2, 2026
Original Paper
High-symmetry ill-fitting subunits in 3D form aggregates of all dimensions
arXiv · 2604.01109
The Takeaway
Scientists found that 'ill-fitting' 3D blocks naturally self-assemble into long filaments or thin layers to minimize the mechanical stress of their bad fit. This suggests that complex biological structures like the fibers seen in diseases may be a simple geometric consequence of building blocks that aren't quite the right shape.
From the abstract
Proteins can combine into functional elements in living cells or self-assemble into unwanted structures in a number of diseases. The resulting aggregates often display filamentous morphologies across a large range of protein shapes and molecular interactions. This has led to the suggestion that filament formation could be a generic outcome of the aggregation of geometrically complex, ill-fitting objects, although such a mechanism has not been demonstrated in three dimensions. To address this pro