Amyloids and prions in plants: Facts and perspectives

ABSTRACT

Amyloids represent protein fibrils that have highly ordered structure with unique physical and chemical properties. Amyloids have long been considered lethal pathogens that cause dozens of incurable diseases in humans and animals. Recent data show that amyloids may not only possess pathogenic properties but are also implicated in the essential biological processes in a variety of prokaryotes and eukaryotes. Functional amyloids have been identified in archaea, bacteria, fungi, and animals, including humans. Plants are one of the most poorly studied groups of organisms in the field of amyloid biology. Although amyloid properties have not been shown under native conditions for any plant protein, studies demonstrating amyloid properties for a set of plant proteins in vitro or in heterologous systems in vivo have been published in recent years. In this review, we systematize the data on the amyloidogenic proteins of plants and their functions and discuss the perspectives of identifying novel amyloids using bioinformatic and proteomic approaches.

KEYWORDS:

• Amyloid
• prion
• LD
• WALTZ
• SARP
• PSIA
• AFP
• plant
• yeast
• A. thaliana
• S. cerevisiae

ABBREVIATIONS

AFP	=	Autonomous Flowering Pathway
EPS	=	Extracellular Polymeric Substances
HPLC	=	High Performance Liquid Chromatography
LPS	=	Lowest Probability Subsequences
PSIA	=	Proteomic Screening and Identification of Amyloids
SDS	=	Sodium Dodecyl Sulfate
Sarkosyl	=	Sodium lauroyl sarcosinate
SARP	=	Sequence Analysis Based on the Ranking of Probabilities
TAPI	=	Technique for Amyloid Purification and Identification; The standard single-letter amino acid code is used

DISCLOSURE OF POTENTIAL CONFLICTS OF INTEREST

Authors declare no potential conflicts of interest.

FUNDING

This work was financially supported by a grant from the Russian Science Foundation (Project No 17-16-01100).