α-Synuclein V15A Variant in Familial Parkinson's Disease Exhibits a Weaker Lipid-Binding Property

Mov Disord. 2022 Oct;37(10):2075-2085. doi: 10.1002/mds.29162. Epub 2022 Jul 27.

Abstract

Background: The α-Synuclein (α-Syn) V15A variant has been found in two Caucasian families with Parkinson's disease (PD). However, the significance of this missense variant remained unclear.

Objective: We sought to elucidate whether V15A could increase aggregation or change phospholipid affinity.

Methods: A sequencing analysis for the SNCA encoding α-Syn from 875 patients with PD and 324 control subjects was performed. Comparing with known pathogenic missense variants of α-Syn, A30P, and A53T, we analyzed the effects of V15A on binding to phospholipid membrane, self-aggregation, and seed-dependent aggregation in cultured cells.

Results: Genetic screening identified SNCA c.44 T>C (p.V15A) from two Japanese PD families. The missense variant V15A was extremely rare in several public databases and predicted as pathogenic using in silico tools. The amplification activity of α-Syn V15A fibrils was stronger than that of wild-type α-Syn fibrils.

Conclusions: The discovery of the V15A variant from Japanese families reinforces the possibility that the V15A variant may be a causative variant for developing PD. V15A had a reduced affinity for phospholipids and increased propagation activity compared with wild-type. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Keywords: familial Parkinson's disease; genetic screening; phospholipids; protein aggregation; α-Synuclein.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Humans
  • Mutation, Missense
  • Parkinson Disease* / metabolism
  • Phospholipids
  • alpha-Synuclein* / genetics
  • alpha-Synuclein* / metabolism

Substances

  • alpha-Synuclein
  • Phospholipids
  • SNCA protein, human