N-acetylation of α-synuclein enhances synaptic vesicle clustering mediated by α-synuclein and lysophosphatidylcholine

Elife. 2024 Dec 27:13:RP97228. doi: 10.7554/eLife.97228.

Abstract

Previously, we reported that α-synuclein (α-syn) clusters synaptic vesicles (SV) Diao et al., 2013, and neutral phospholipid lysophosphatidylcholine (LPC) can mediate this clustering Lai et al., 2023. Meanwhile, post-translational modifications (PTMs) of α-syn such as acetylation and phosphorylation play important yet distinct roles in regulating α-syn conformation, membrane binding, and amyloid aggregation. However, how PTMs regulate α-syn function in presynaptic terminals remains unclear. Here, based on our previous findings, we further demonstrate that N-terminal acetylation, which occurs under physiological conditions and is irreversible in mammalian cells, significantly enhances the functional activity of α-syn in clustering SVs. Mechanistic studies reveal that this enhancement is caused by the N-acetylation-promoted insertion of α-syn's N-terminus and increased intermolecular interactions on the LPC-containing membrane. N-acetylation in our work is shown to fine-tune the interaction between α-syn and LPC, mediating α-syn's role in synaptic vesicle clustering.

Keywords: alpha-synuclein; lysophosphatidylcholine; membrane binding; molecular biophysics; mouse; structural biology; synaptic vesicle.

MeSH terms

  • Acetylation
  • Animals
  • Humans
  • Lysophosphatidylcholines* / metabolism
  • Protein Processing, Post-Translational
  • Synaptic Vesicles* / metabolism
  • alpha-Synuclein* / chemistry
  • alpha-Synuclein* / metabolism

Substances

  • alpha-Synuclein
  • Lysophosphatidylcholines