title: Parathyroid-specific double knockout of Gq and G11 alpha-subunits leads to a phenotype resembling germline knockout of the extracellular Ca2+ -sensing receptor.
abstract: Germline knockout of the extracellular Ca2+ -sensing receptor (CaR) leads to a phenotype that includes severe hypercalcemia, hyperparathyroidism, relative hypocalciuria, skeletal abnormalities, retarded growth, and early postnatal death. To investigate the role of heterotrimeric G proteins in CaR signaling, we used cre/lox technology to delete the respective alpha-subunits of Gq and G11 selectively in parathyroid cells. Mice that were PTH-Cre(+/-); Gnaq(flox/flox); Gna11(-/-) (PTH-Galphaq/Galpha11 -double knockouts) were viable, but showed all the features of germline knockout of the CaR except hypocalcuria. Our results demonstrate the critical role of both Gq and G11 in mediating inhibition of PTH secretion by extracellular Ca2+.
authors.affiliation: Pharmakologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany. nina.wettschureck@pharma.uni-heidelberg.de
authors.forename: Nina
authors.initials: N
authors.lastname: Wettschureck
authors.forename: EunAh
authors.initials: E
authors.lastname: Lee
authors.forename: Steven K
authors.initials: SK
authors.lastname: Libutti
authors.forename: Stefan
authors.initials: S
authors.lastname: Offermanns
authors.forename: Pamela G
authors.initials: PG
authors.lastname: Robey
authors.forename: Allen M
authors.initials: AM
authors.lastname: Spiegel
mesh_terms: D000818:Animals; D001851:Bone Diseases, Metabolic / Q000378:metabolism; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D004573:Electrolytes / Q000378:metabolism; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D008954:Models, Biological; D010280:Parathyroid Glands / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000378:metabolism; D010641:Phenotype; D011859:Radiography; D044169:Receptors, Calcium-Sensing / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: D004573:Electrolytes; D010281:Parathyroid Hormone; D044169:Receptors, Calcium-Sensing; D010738:Type C Phospholipases; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; D002118:Calcium