Fig. 3: Location of secondary structures in the vitreous body and heart ATTR fibrils.
From: Structural basis for transthyretin amyloid formation in vitreous body of the eye
a Primary sequence of TTR Val30Met with secondary structure elements indicated for natively folded TTR, heart ATTR fibrils, and vitreous ATTR fibrils. b Cα trace of one protofilament of vitreous ATTR twisted-dimer fibril protein. The secondary structures in b–e are color-coded as in a. c Cα trace of the protofilament of heart ATTR fibril protein (PDB-ID 6SDZ). The black asterisk marks an internal cavity not present in the vitreous fibril protein. The red asterisks mark two densities not present in vitreous ATTR. d Superposition of the vitreous and heart fibril protein structures shown in b and c. e Structural changes in the Gly57–Ile84 region. In particular, Ala81–Leu82 have swapped their positions. f Electrostatic surface potentials of vitreous twisted-dimers (left) and heart fibrils (right). The black arrows indicate identical positions on the two fibrils with markedly different surfaces and electrostatic potentials due to the conformational changes shown in (d, e).
