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Grudinina, N. A.

Publications and source records attributed to Grudinina, N. A..

3 recordsLinked to original sources

Spontaneous formation of different forms of alpha-synuclein fibrils from a recombinant protein

Alpha-synuclein is a protein, the conformational changes of which lead to the development of such socially significant diseases as Parkinsons disease and amyotrophic lateral sclerosis. The methods for differential diagnostics of these diseases based on the use of alpha-synuclein in a non-native conformation obtained from patients as a seed for inducing fibrillogenesis and studying the morphology of the resulting amyloid-like fibrils were described in a number of studies. The authors associate such properties of the seed with the presence of post-translational modifications in the protein obtained from patients. At the same time, the production of fibrils differing in morphology from recombinant alpha-synuclein under various conditions of fibrillogenesis is also described. In this work, we show that the formation of morphologically distinct fibril types from recombinant alpha-synuclein lacking post-translational modifications is possible under the same conditions, and that spontaneously arising different fibril types, when used as a seed for fibrillogenesis, lead to the formation of recombinant protein fibrils morphological similar to the parental seed. The results of the work can be used both in studying the fundamental mechanisms of conformation transfer and in developing test systems for synucleinopathies.

molecular biology↗

Time machine: Can a dye from 1928 be re-purposed for modern, fluorescence-based detection of amyloid-like fibrils?

This manuscript describes the chemical synthesis of a compound similar to fluorene and Congo red, including characterization of its spectral properties. It was shown that the dye, during interaction with amyloid-like fibrils of several proteins (lysozyme, insulin, and beta-2-microglobulin), has the ability to change fluorescent spectrum. In contrast, monomeric forms of these proteins did not induce significant spectral changes.

biochemistry↗

Changing Times: Fluorescence-lifetime Analysis of Amyloidogenic SF-IAPP Fusion Protein

The fluorescence lifetime of the superfolder green fluorescent protein (SF) and the SF protein fused with islet amyloid polypeptide (SF-IAPP) were studied in polyacrylamide gel. It was shown that the SF average fluorescence lifetime under these conditions slightly differs from that of the SF-IAPP monomer. SF-IAPP does not lose the ability to form amyloid-like fibrils; meanwhile, the average fluorescence lifetime of the fusion protein in fibrils is reduced. We propose the application of Fluorescent-lifetime Imaging Microscopy (FLIM) to the measurement of average fluorescence lifetimes of fusion proteins (amyloidogenic protein-SF) in the context of studies using cellular models of conformational diseases.

biophysics↗