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Does liquid-liquid phase separation drive peptide folding?

ABSTRACT: Proline-arginine (PR) dipeptide repeats have been shown to undergo liquid-liquid phase separation and are an example of a growing number of intrinsically disordered proteins that can assemble into membraneless organelles. These structures have been posited as nucleation sites for pathogenic protein aggregation. As such, a better understanding of the effects that the increased local concentration and volumetric crowding within droplets have on peptide secondary structure is necessary. Herein we use Fourier transform infrared (FTIR) and two-dimensional infrared (2DIR) spectroscopy to show that formation of droplets by PR₂₀ accompanies changes in the amide-I spectra consistent with folding into poly-proline helical structures.

SUBMITTER: Edun DN

PROVIDER: S-EPMC8179267 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Does liquid-liquid phase separation drive peptide folding?

Edun Dean N DN Flanagan Meredith R MR Serrano Arnaldo L AL

Chemical science 20201229 7

Proline-arginine (PR) dipeptide repeats have been shown to undergo liquid-liquid phase separation and are an example of a growing number of intrinsically disordered proteins that can assemble into membraneless organelles. These structures have been posited as nucleation sites for pathogenic protein aggregation. As such, a better understanding of the effects that the increased local concentration and volumetric crowding within droplets have on peptide secondary structure is necessary. Herein we u ...[more]

PMID: 34164013

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