Filaments aggregates

Lonsdale-Eccles, J. D., Teller, D. C., and Dale, B. A. (1982). Characterization of a phosphorylated form of the intermediate filament-aggregating protein filaggrin. Biochemistry 21, 5940-5948. 

The sequence of appearance, relative amounts, and final relationships of cell components that survive lysis are presented diagrammatically in Figure 11. The smallest filaments that have been isolated (35 A thick) have low sulfur content (32). They thicken to 60-90 A with addition of sulfur-rich protein (demonstrated by heavy metal staining) (32, 64) and histidine-rich protein (demonstrated with radioactive labeling) (49). Five to 10 of these thickened filaments aggregate to form fibrils that average 250 A in diameter (70). Meanwhile, KH and ER protein accumulate until the cell is lysed when they are mixed and dispersed (47) to coat the 250-A fibrils (70). The coated fibrils are submerged in a matrix that includes nucleoproteins and nonfibrous proteins these incorporate about 10 times more sulfur than the fibrils (32). The insoluble fibrils and matrix constitute about 65% of the cornified cell (66) other components include 10% soluble keratin, 10% dialyzable substances (amino acids, etc.), 7-9% lipids, and about 5% membrane protein (65, 66). 

Figure 14. Proposed structure and composition of hygroscopic elements within stratum corneum. A composite of three drawings filaments aggregate to form tonofibrils of 250-A diameter (14A), adapted from Ref. 70 lysed lipids and proteins form an 80-A coating (14B) around the tonofibrils, adapted from Refs. 47, 96, and 97. The depicted relationship of bimoaal protein and lipids to form hydrophilic surfaces (14C) is adapted from Ref. 98.

Trioctahedral smectite (stevensite) was common in Mg-carbonate crusts and moonmilk (Polyak and Gtiven, 2000). Most of the smectite appeared fibrous, or less commonly as films. The fibers and films formed filamentous aggregates that enveloped dolomite and huntite crystals (Fig 4). 

Figure 4. SEM images of filamentous aggregates of faioct ech al smectite enveloping dolomite crystals in dolomite crust (Carlsbad Cavern). Image on die right was modified from Polyak and Guven (2000). Arrows point to coated dolomite rhombs.

Figure 7 Part of a large paracrystalline aggregate of Xenopus lamin-A, expressed in E. coli. Note the characteristic 25 nm periodicity along the filamentous aggregate. Bar=0.5nm. (The sample material was kindly provided by Gieffers C and Krohne G and the specimen was produced from a solution of protein in 2 mol I ammonium acetate by the negative staining-carbon film procedure.)...

There are morphologial similarities between amyloid protein and infectious protein in scrapie and Creutzfeld-Jakob disease, and protein deposits in Alzheimer s disease, all of which are associated with progressive and irreversible degeneration of nervous function, leading to death. [P.A.Merz etal. Nature 306 (1983) 474- 76 H.Diringer etal. ibid. 476-478] In Alzheimer s disease there is invariably a progressive accumulation of filamentous aggregates of amy-... 

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