PTH1R and hypoparathyroidism: Prolonged signaling responses have also been observed upon covalent tethering of a GPCR ligand to its receptor.28 Compounds with a long duration of action are useful in a variety of contexts29, such as long-acting PTHR1 agonists which are used to treat hypoparathyroidism.29, 30 The findings here encourage exploration of Nb conjugation to facilitate the rational design of long-lasting ligands.