Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Overview of prefibrillar assemblies as a heterogeneous snap-shot, imaged by cryo-EM. Typical classification of assemblies, and approximate number of Aβ 42 monomers is indicated (A). Abinitio 3D reconstruction from 2.5 million particles, 3 structures from 10 are shown. Oligomer (blue) from 180k particles; Curvilinear Protofibril (green) 322k particles and Annular assembly (pink) 298 particles. Scale Bar 20 Å for 2D class averages; 50 Å for 3D structures.

Article Snippet: Importantly, the 3D cryo-EM structure shown in Figure S5 contains an internal channel running through the middle of the structure.

Techniques: Cryo-EM Sample Prep

Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Cryo-EM 2D class averages of typical oligomers and curvilinear protofibrils. 209,000 particles in total, scale bar 20 Å. The class averages have been arranged in increasing length. Top row 25-50 Å, second row 60-80 Å; 3 rd row 90-105 Å; and bottom row 100-140 Å, (A). Distribution of oligomer and curvilinear protofibrils length. Taken from half a million particles; 95 % of particles are less than 90 Å long (B). Density profiles of the protofibril diameter. Six profiles for each row (Red, orange yellow left side images. Green, blue and purple on the right side) (C). Diameters observed for each row. The mean diameter for class averages in rows 2, 3 and 4 are consistently 28 +/-1 Å (standard dev.) (D).

Article Snippet: Importantly, the 3D cryo-EM structure shown in Figure S5 contains an internal channel running through the middle of the structure.

Techniques: Cryo-EM Sample Prep

Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Cryo-ET 3D tomograms. (A) Typical oligomers, side and orthogonal top view are shown (top row), and curvilinear protofibrils (row 2 & 3). The cryo-ET single particles have a close resemblance to the cryo-EM class averages, shown in . Lengths of the long axis are: Top row 25-50 Å; 2 nd row 60-100 Å; 3 rd row 100-300 Å. Images are presented as sums of 5-10 2D slices, each 7.8 Å thick. Scale Bar = 100 Å. (B) Density profiles show that the particles have a consistent diameter of ca . 2.8 nm.

Article Snippet: Importantly, the 3D cryo-EM structure shown in Figure S5 contains an internal channel running through the middle of the structure.

Techniques: Tomography, Cryo-EM Sample Prep

Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Cryo-EM 3D reconstruction of Aβ 42 annular oligomers. 2D averages (A) and 3D reconstruction (B) from 6k single particles suggests the structure has an internal pore. External Diameter, of top view is 65-55 Å; Length of channel is 54 Å; Volume suggests 12-16 Aβ 42 molecules. Scale bar: 50 Å for 3D structures, 20 Å for 2D averages.

Article Snippet: Importantly, the 3D cryo-EM structure shown in Figure S5 contains an internal channel running through the middle of the structure.

Techniques: Cryo-EM Sample Prep

Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Overview of prefibrillar assemblies as a heterogeneous snap-shot, imaged by cryo-EM. Typical classification of assemblies, and approximate number of Aβ 42 monomers is indicated (A). Abinitio 3D reconstruction from 2.5 million particles, 3 structures from 10 are shown. Oligomer (blue) from 180k particles; Curvilinear Protofibril (green) 322k particles and Annular assembly (pink) 298 particles. Scale Bar 20 Å for 2D class averages; 50 Å for 3D structures.

Article Snippet: 7 nm, which closely matches the cryo-EM 3D reconstructions shown in and S5, the length of the internal channel appears a little smaller at ca .

Techniques: Cryo-EM Sample Prep

Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Cryo-EM 2D class averages of typical oligomers and curvilinear protofibrils. 209,000 particles in total, scale bar 20 Å. The class averages have been arranged in increasing length. Top row 25-50 Å, second row 60-80 Å; 3 rd row 90-105 Å; and bottom row 100-140 Å, (A). Distribution of oligomer and curvilinear protofibrils length. Taken from half a million particles; 95 % of particles are less than 90 Å long (B). Density profiles of the protofibril diameter. Six profiles for each row (Red, orange yellow left side images. Green, blue and purple on the right side) (C). Diameters observed for each row. The mean diameter for class averages in rows 2, 3 and 4 are consistently 28 +/-1 Å (standard dev.) (D).

Article Snippet: 7 nm, which closely matches the cryo-EM 3D reconstructions shown in and S5, the length of the internal channel appears a little smaller at ca .

Techniques: Cryo-EM Sample Prep

Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Cryo-ET 3D tomograms. (A) Typical oligomers, side and orthogonal top view are shown (top row), and curvilinear protofibrils (row 2 & 3). The cryo-ET single particles have a close resemblance to the cryo-EM class averages, shown in . Lengths of the long axis are: Top row 25-50 Å; 2 nd row 60-100 Å; 3 rd row 100-300 Å. Images are presented as sums of 5-10 2D slices, each 7.8 Å thick. Scale Bar = 100 Å. (B) Density profiles show that the particles have a consistent diameter of ca . 2.8 nm.

Article Snippet: 7 nm, which closely matches the cryo-EM 3D reconstructions shown in and S5, the length of the internal channel appears a little smaller at ca .

Techniques: Tomography, Cryo-EM Sample Prep

Journal: bioRxiv

Article Title: Structural architecture of amyloid-β oligomers, curvilinear protofibrils and annular assemblies, imaged by cryo-EM and cryo-ET

doi: 10.1101/2024.03.01.582902

Figure Lengend Snippet: Cryo-EM 3D reconstruction of Aβ 42 annular oligomers. 2D averages (A) and 3D reconstruction (B) from 6k single particles suggests the structure has an internal pore. External Diameter, of top view is 65-55 Å; Length of channel is 54 Å; Volume suggests 12-16 Aβ 42 molecules. Scale bar: 50 Å for 3D structures, 20 Å for 2D averages.

Article Snippet: 7 nm, which closely matches the cryo-EM 3D reconstructions shown in and S5, the length of the internal channel appears a little smaller at ca .

Techniques: Cryo-EM Sample Prep