SNCA and Parkinson disease: A number of proteins associated with mPD (α-synuclein, DJ-1, PINK1, Parkin, LRRK2) are concentrated at MERCs under normal conditions where they mediate diverse, often non-standard, functions (Ottolini et al., 2013; Guardia-Laguarta et al., 2014; Gautier et al., 2016; Gelmetti et al., 2017; Basso et al., 2018; Parrado-Fernandez et al., 2018; Toyofuku et al., 2020), and PD-causing mutations in these proteins are associated with disrupted mitochondria-ER contact and communication.