Molecular & Cellular Toxicology

, Volume 15, Issue 1, pp 103–109 | Cite as

Sumoylated α-synuclein translocates into the nucleus by karyopherin α6

  • Seungjin Ryu
  • Inkyung Baek
  • Hyunjeong LiewEmail author
Original Paper



α-Synuclein (α-SYN) is uniquely found in the brains of Parkinson’s disease (PD) patients and it has been the major target of PD research for many years. The translocation of α-SYN into the nucleus of neuronal cells is a well-known fact but the mode of nuclear entry and its functions thereafter are not well defined.


By utilizing a model cell line and primary cultured neurons, we have investigated a plausible mechanism of α-SYN nuclear translocation and its pathophysiological roles in the nucleus of cells with neuronal phenotypes.


We, first, identified that cytosolic α-SYN proteins bind to karyopherin alpha6 proteins only after sumoylation (i.e. SUMO2/3 binding) and then transits through the nuclear pore complex (NPC) as a complexed entity.


We investigated that the nuclear translocation of α-SYN is critically required for its nuclear translocation and that this process is mediated by karyopherin alpha6.


α-Synuclein (α-SYN) Small ubiquitin-related modifier proteins (SUMO) Karyopherin (KPNA) 


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Copyright information

© The Korean Society of Toxicogenomics and Toxicoproteomics and Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Department of Comparative MedicineYale School of MedicineNew HavenUSA
  2. 2.Department of Foods and NutritionKookmin UniversitySeoulRepublic of Korea
  3. 3.Department of Bio and Fermentation Convergence Technology, Department of Integrative Biomedical Science and EngineeringKookmin UniversitySeoulRepublic of Korea

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