Auxilin Underlies Progressive Locomotor Deficits and Dopaminergic Neuron Loss in a Drosophila Model of Parkinson's Disease

Cell Rep. 2017 Jan 31;18(5):1132-1143. doi: 10.1016/j.celrep.2017.01.005.

Abstract

Parkinson's disease (PD) is a common neurodegenerative disorder that exhibits motor and non-motor symptoms, as well as pathological hallmarks, including dopaminergic (DA) neuron death and formation of α-synuclein (α-Syn) Lewy bodies. Cyclin-G-associated kinase (GAK), a PD susceptibility gene identified through genome-wide association studies (GWAS), is a ubiquitous serine/threonine kinase involved in clathrin uncoating, though its PD-related function remains elusive. Here, we implicate the Drosophila GAK homolog, auxilin (aux), in a broad spectrum of parkinsonian-like symptoms. Downregulating aux expression leads to progressive loss of climbing ability, decreased lifespan, and age-dependent DA neuron death similar to α-Syn overexpression. Reduced aux expression further enhances and accelerates α-Syn-mediated DA neuron loss. Flies with reduced aux expression are more sensitive to the toxin paraquat, suggesting that genetic and environmental factors intertwine. Taken together, these findings decipher a pivotal role for GAK/aux and suggest mechanisms underlying PD.

Keywords: DA; GAK; PD; Parkinson’s disease; aux; auxilin; cyclin-G-associated kinase; dopaminergic neuron loss; locomotor deficits; longevity; paraquat; α-synuclein.

MeSH terms

  • Animals
  • Auxilins / metabolism*
  • Clathrin / metabolism
  • Dopamine / metabolism*
  • Dopaminergic Neurons / metabolism*
  • Down-Regulation / physiology
  • Drosophila / metabolism
  • Genome-Wide Association Study / methods
  • Lewy Bodies / metabolism
  • Locomotion / physiology*
  • Neurodegenerative Diseases / metabolism
  • Parkinson Disease / metabolism*
  • Protein Serine-Threonine Kinases / metabolism
  • alpha-Synuclein / metabolism

Substances

  • Auxilins
  • Clathrin
  • alpha-Synuclein
  • Protein Serine-Threonine Kinases
  • Dopamine