ROR gamma, a NR1 Thyroid Hormone-Like receptor, has been shown to affect thymopoiesis, bone metabolism, T-cell apoptosis, and lymphoid organogenesis. ROR gamma has been shown to promote thymocyte survival by activating the expression of the antiapoptotic protein Bcl-x(L). ROR gamma is also required for the development of lymph nodes and Peyer's patches. It has been shown that ROR gamma t, a thymus-specific isoform of ROR gamma from mouse, inhibits Fas ligand expression and cytokine secretion in immature thymocytes. ROR gamma binds as a monomer to response elements composed of a single core motif, GGTCA, preceded by a 6 bp AT-rich sequence. ROR gamma expression has been documented in mouse thymus, adipose, bone, skeletal muscle, liver, and kidney, and in Human skeletal muscle. ESTs have been isolated from Human tissue libraries, including cancerous head/neck, germ cell, and prostate, and normal colon, head/neck, lung, liver/spleen, and pancreas.