Amyotrophic lateral sclerosis-linked UBQLN2 mutants inhibit endoplasmic reticulum to Golgi transport, leading to Golgi fragmentation and ER stress

Mark Halloran, Audrey M.G. Ragagnin, Marta Vidal, Sonam Parakh, Shu Yang, Benjamin Heng, Natalie Grima, Hamideh Shahheydari, Kai-Ying Soo, Ian Blair, Gilles J. Guillemin, Vinod Sundaramoorthy, Julie D. Atkin*

*Corresponding author for this work

Research output: Contribution to journalArticle


Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are fatal neurodegenerative diseases that are related genetically and pathologically. Mutations in the UBQLN2 gene, encoding the ubiquitin-like protein ubiquilin2, are associated with familial ALS/FTD, but the pathophysiological mechanisms remain unclear. Here, we demonstrate that ALS/FTD UBQLN2 mutants P497H and P506T inhibit protein transport from the endoplasmic reticulum (ER) to the Golgi apparatus in neuronal cells. In addition, we observed that Sec31-positive ER exit sites are clustered in UBQLN2T487I patient spinal cord tissues. Both the ER–Golgi intermediate (ERGIC) compartment and the Golgi become disorganised and fragmented. This activates ER stress and inhibits ER-associated degradation. Hence, this study highlights perturbations in secretory protein trafficking and ER homeostasis as pathogenic mechanisms associated with ALS/FTD-associated forms of UBQLN2.

Original languageEnglish
Number of pages15
JournalCellular and Molecular Life Sciences
Publication statusE-pub ahead of print - 4 Dec 2019



  • Amyotrophic lateral sclerosis
  • ER stress
  • ER-Golgi trafficking
  • Golgi fragmentation
  • Ubiquilin-2
  • Unfolded protein response

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