Cloning of a type I cytokine receptor most related to the IL-2 receptor beta chain

We have identified a type I cytokine receptor, which we have termed novel i nterleukin receptor(NILR), that is most related to the IL-2 receptor beta c hain (IL-2R beta) and physically adjacent to the IL-4 receptor ru chain gen e on chromosome 16, NILR mRNA is most highly expressed in thymus and spleen , and is induced by phyto-hemagglutinin in human peripheral blood mononucle ar cells. NILR protein was detected on human 7 cell lymphotropic virus type I-transformed T cell lines, Raji B cells, and YT natural killer-like cells . Artificial homodimerization of the NILR cytoplasmic domain confers prolif eration to Ba/F3 murine pro-B cells but not to 32D myeloid progenitor cells or CTLL-2 murine helper T cells. In these latter cells, heterodimerization of IL-2R beta and the common cytokine receptor gamma chain (gamma(c)) cyto plasmic domains allows potent proliferation, whereas such heterodimerizatio n of NILR with ye does not. This finding suggests that NILR has signaling p otential but that a full understanding of its signaling partner(s) is not y et clear. Like IL-2R beta, NILR associates with Jak1 and mediates stats act ivation.