The crystal structure of amyloidogenic Leu55 --> Pro transthyretin variant reveals a possible pathway for transthyretin polymerization into amyloid fibrils.Sebastiao, M.P., Saraiva, M.J., Damas, A.M.
(1998) J.Biol.Chem. 273: 24715-24722
- PubMed: 9733771
- PubMed Abstract:
- Transthyretin Pro55, a Variant Associated with Early-Onset, Aggressive, Diffuse Amyloidosis with Cardiac and Neurologic Involvement
Jacobson, D.R.,Mcfarlin, D.E.,Kane, I.,Buxbaum, J.N.
(1992) Hum.Genet. 89: 353
- Crystallization and Preliminary X-Ray Diffraction Studies of Leu55Pro Variant Transthyretin
Sebastiao, P.,Dauter, Z.,Saraiva, M.J.,Damas, A.M.
(1996) Acta Crystallogr.,Sect.D 52: 566
- Transthyretin Mutation Leu-55-Pro Significantly Alters Tetramer Stability and Increases Amyloidogenicity
Mccutchen, S.L.,Colon, W.,Kelly, J.W.
(1993) Biochemistry 32: 12119
The x-ray crystal structure of the amyloidogenic Leu55 --> Pro transthyretin (TTR) variant, implicated as the causative agent in early-onset familial amyloidotic polyneuropathy (Jacobson, D. R., McFarlin, D. E., Kane, I., and Buxbaum, J. N. (1992) Hu ...
The x-ray crystal structure of the amyloidogenic Leu55 --> Pro transthyretin (TTR) variant, implicated as the causative agent in early-onset familial amyloidotic polyneuropathy (Jacobson, D. R., McFarlin, D. E., Kane, I., and Buxbaum, J. N. (1992) Hum. Genet. 89, 353-356), has been solved by molecular replacement, refined at 2.7 A to a Rcryst value of 0.190 (Fobs > 2.0sigma), and compared with wild-type transthyretin to understand the molecular mechanism(s) involved in amyloidogenesis. Leu55 --> Pro TTR crystallizes in space group C2, with eight monomers in the asymmetric unit, and the observed packing contacts are considerably different from those described for the wild-type protein. Refinement of the crystal structure shows that the proline for leucine substitution disrupts the hydrogen bonds between strands D and A, resulting in different interface contacts. Based on the assumption that the observed packing contacts may be significant for amyloidogenesis, a model for the TTR amyloid is proposed. It consists of a tubular structure with inner and outer diameters approximately of 30 and 100 A and four monomers per cross-section.
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