NR4A1 and Parkinson disease: Given the roles of Nur77 in the neuroinflammation, autophagy, and mitochondrial dysfunctions in PD, we sought to mechanistically investigate: (1) the direct involvement of Nur77 in mitochondrial dysfunctions; (2) the associations between Nur77 and ER stress, and 3) the autophagy association between Nur77 verse PINK1 and Parkin in 6-OHDA-lesioned pheochromocytoma (PC12) cells.