High-Throughput Microplate-Based Fluorescence Assays for Studying Stochastic Aggregation of Superoxide Dismutase-1

Methods Mol Biol. 2019:1873:93-108. doi: 10.1007/978-1-4939-8820-4_6.

Abstract

Investigating in vitro kinetics of superoxide dismutase-1 (SOD1) aggregation with high-throughput microplate-based assays provides valuable information regarding SOD1 pathogenesis in amyotrophic lateral sclerosis (ALS) and opens venues for the development of effective therapies. In this chapter, we first explain the step-by-step purification and demetallation of wild-type (WT) and ALS-variant SOD1 proteins from Saccharomyces cerevisiae (baker's yeast). We then describe the methodology for a microplate-based fluorescence assay that is used to study real-time kinetics of metal-free (apo)-SOD1 aggregation. This technique is highly sensitive, semiautomated, requires minimum modifications to protein, and produces a plethora of data in a short period of time. We also describe a new approach for extracting clinically relevant information from SOD1 aggregation data using Kaplan-Meier estimators.

Keywords: Amyloid; Amyotrophic lateral sclerosis; Cu, Zn superoxide dismutase; Demetallation; Fibrillization; Fluorescence spectroscopy; Protein purification; Thioflavin-T.

MeSH terms

  • Biological Assay / methods*
  • Data Interpretation, Statistical
  • High-Throughput Screening Assays*
  • Humans
  • Kinetics
  • Protein Aggregates
  • Recombinant Proteins / genetics
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Spectrometry, Fluorescence* / methods
  • Superoxide Dismutase-1 / genetics
  • Superoxide Dismutase-1 / isolation & purification
  • Superoxide Dismutase-1 / metabolism*

Substances

  • Protein Aggregates
  • Recombinant Proteins
  • Superoxide Dismutase-1