Table 1 Non-exhaustive list of protein misfolding diseases with their associated peptides or proteins, and in vitro and ex vivo structures of corresponding amyloid fibrils. Putative mechanisms of aggregation and toxicity are also indicated

Alzheimer’s disease (AD)

Amyloid-β (Aβ)

Tau (3R + 4R)

40 or 42

352–441

Aβ: Oligomers [3, 16, 17]

Tau: Oligomers [18,19,20]

Secondary nucleation [21, 22]

Secondary nucleation [23]

Aβ₄₀ [24]

Aβ₄₂ [25]

Tau [26]

Aβ₄₀ [27, 28]

Aβ₄₂ [5]

Tau [29, 30]

Parkinson’s disease (PD)

⍺-synuclein

140

Oligomers [31,32,33]

Condition-dependent [34], including lipid-induced aggregation [35]

[36,37,38,39]

[40,41,42]

Dementia with Lewy Bodies (DLB)

⍺-synuclein

140

Pre-synaptic aggregates [43] & oligomers [44, 45]

Not yet known, secondary pathways [46]

-

[40, 47]

PD dementia (PDD)

⍺-synuclein

140

Not yet known, possibly oligomers [48]

-

-

[40]

Multiple system atrophy (MSA)

⍺-synuclein

140

Oligomers [49, 50]

-

-

[42, 51]

Huntington’s disease (HD)

Huntingtin

variable

Not yet known, possibly oligomers [52,53,54]

Possibly stochastic nucleation [55]

[56]

-

Chronic traumatic encephalopathy (CTE)

Tau (3R + 4R)

352–441

Not yet known

Not yet known, possibly secondary pathways [57]

[26]

[58]

Pick’s disease (PiD)

Tau (3R)

352–410

Not yet known

Not yet known, possibly secondary pathways [59]

-

[60]

Corticobasal degeneration (CBD)

Tau (4R)

383–441

Not yet known

Not yet known, possibly secondary pathway [61]

-

[62]

Progressive supranuclear palsy (PSP)

Tau (4R)

383–441

Not yet known

-

-

[4]

Argyrophilic grain disease (AGD)

Tau (4R)

383–441

Not yet known

Not yet known, possibly secondary pathways [63]

-

[4]

Globular glial tauopathy (GGT)

Tau (4R)

383–441

Not yet known

Not yet known, possibly secondary pathways [64]

-

[4]

Spongiform encephalopathies

Prion protein (PrP)

208

PrP^Sc [65], possibly oligomers [66, 67]

Fragmentation [68]

[69,70,71,72]

Mouse PrP

[73, 74]

RML prion [75]

Scrapie [70]

Bovine serum encephalopathy [76]

Type II diabetes

Amylin (IAPP)

37

Oligomers [77, 78]

Secondary nucleation [79]

[80, 81]

[82]

Cataracts

Crystallins

175

Aggregates of damaged proteins [83, 84]

-

-

-

AA amyloidosis

Serum amyloid A

104

Fibrils [85] and oligomers [86]

Secondary pathways [87]

[85, 88]

[85, 88]

Transthyretin amyloidosis

ATTRwt

Val30Met ATTR

127

Various species [89,90,91]

-

-

[92, 93]

Ig-related amyloidosis (AL)

Immunoglobulin light chain

Proteolytic fragments

Fibrils [94] and oligomers [95]

Not yet known, seed-competent [96]

-

[97, 98]