Introduction: Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide and is characterised by progressive loss of dopaminergic neurons in the midbrain. Neuronal death is often accompanied by the formation of Lewy bodies, large perinuclear inclusion bodies primarily composed of misfolded [alpha]-synuclein. Accumulation of misfolded proteins is a central paradigm in the progression of neurodegeneration and results primarily from the dysregulation of protein homeostasis. The unfolded protein response (UPR) of the endoplasmic reticulum (ER) plays a central role in protein homeostasis, along with ER-phagy, a specific form of autophagy. Dysregulation of the UPR and ER-phagy have recently been linked to neurodegeneration, though their specific role in PD remains unknown. [...]