Fig. 2
From: Parkinson's in the bone
PD risk genes that regulate PTH1R signaling and bone homeostasis. A The PD risk gene, VPS35 (a key component of Retromer) plays an important role in regulating PTH1R trafficking, turning off PTH signaling, and promoting its catabolic function. B The PD risk gene, NR4A2, is up-regulated by PTH-PTH1R-cAMP signaling, which then acts as a transcriptional activator to induce gene expression such as fibroblast growth factor 23 (FGF23) and osteopontin (OPN)