Synphilin-1-binding protein NUB1 is colocalized with nonfibrillar, proteinase K-resistant α-synuclein in presynapses in Lewy body disease

J Neuropathol Exp Neurol. 2011 Oct;70(10):879-89. doi: 10.1097/NEN.0b013e3182303745.

Abstract

α-Synuclein is a major component of Lewy bodies in Parkinson disease (PD) and dementia with Lewy bodies (DLB). We recently showed that abnormal α-synuclein with resistance to proteinase K (PK) is deposited at presynapses of distinct brain anatomic regions from the early stages of PD and DLB. NUB1, a synphilin-1-binding protein, also accumulates in Lewy bodies, but it is not known whether abnormal α-synuclein is associated with NUB1. Here, we demonstrate that, in the brain of patients with PD and DLB, NUB1 accumulates in the presynapses in the hippocampus, cerebral neocortex, and substantia nigra in which PK-resistant α-synuclein is deposited. Endogenous NUB1 also accumulated with PK-resistant α-synuclein in the presynapses of transgenic mice that express human α-synuclein with an A53T mutation. Immunoelectron microscopy showed that NUB1 is localized to presynaptic nerve terminals where no abnormal filaments are seen. Biochemical analyses showed that NUB1 coexists with abnormal α-synuclein in the brain of DLB patients. These findings suggest that NUB1 along with abnormal α-synuclein is involved in the pathogenesis of Lewy body disease.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Animals
  • Animals, Newborn
  • Brain / pathology*
  • Endopeptidase K / pharmacology
  • Female
  • Gene Expression Regulation, Developmental / genetics
  • Gene Expression Regulation, Developmental / physiology
  • HeLa Cells
  • Humans
  • Lewy Body Disease / metabolism
  • Lewy Body Disease / pathology*
  • Male
  • Mice
  • Mice, Transgenic
  • Middle Aged
  • Mutation / genetics
  • Presynaptic Terminals / metabolism*
  • Synaptophysin / metabolism
  • Transcription Factors / metabolism*
  • Transfection / methods
  • alpha-Synuclein / drug effects
  • alpha-Synuclein / genetics
  • alpha-Synuclein / metabolism*

Substances

  • NUB1 protein, human
  • Synaptophysin
  • Transcription Factors
  • alpha-Synuclein
  • Endopeptidase K