PMID: 25651181

Authors:

Santori FR, Huang P, van de Pavert SA, Douglass EF Jr, Leaver DJ, Haubrich BA, Keber R, Lorbek G, Konijn T, Rosales BN, Rozman D, Horvat S, Rahier A, Mebius RE, Rastinejad F, Nes WD, Littman DR

Title:

Identification of Natural RORgamma Ligands that Regulate the Development of Lymphoid Cells.

Journal:

Cell Metab. 2015 Feb 3;21(2):286-97. doi: 10.1016/j.cmet.2015.01.004.

Abstract:

Mice deficient in the nuclear hormone receptor RORgammat have defective development of thymocytes, lymphoid organs, Th17 cells, and type 3 innate lymphoid cells. RORgammat binds to oxysterols derived from cholesterol catabolism, but it is not clear whether these are its natural ligands. Here, we show that sterol lipids are necessary and sufficient to drive RORgammat-dependent transcription. We combined overexpression, RNAi, and genetic deletion of metabolic enzymes to study RORgamma-dependent transcription. Our results are consistent with the RORgammat ligand(s) being a cholesterol biosynthetic intermediate (CBI) downstream of lanosterol and upstream of zymosterol. Analysis of lipids bound to RORgamma identified molecules with molecular weights consistent with CBIs. Furthermore, CBIs stabilized the RORgamma ligand-binding domain and induced coactivator recruitment. Genetic deletion of metabolic enzymes upstream of the RORgammat-ligand(s) affected the development of lymph nodes and Th17 cells. Our data suggest that CBIs play a role in lymphocyte development potentially through regulation of RORgammat.