Molecular cloning of a human novel type I cytokine receptor related to delta 1/TSLPR

In a search for a human sequence related to a recently identified type I cy tokine receptor delta1, which turned out to be a receptor subunit for a cyt okine called TSLP, we have now identified a novel human type I cytokine rec eptor from a human T lymphocyte cDNA library. The deduced amino acid sequen ce of 371 residues has a typical signal sequence and a membrane-spanning re gion. The mature protein is predicted to have a molecular mass of 39,698 Da . The N-terminal extracellular region contains two fibronectin type III-lik e domains, four conserved cysteine residues, and a WSXWS box-like motif. Th e C-terminal intracellular region contains box 1 and box 2-like motifs. Thu s. it has common characteristics of type I cytokine receptor family members . and we tentatively termed this protein CRLF2, which stands for cytokine r eceptor-like factor 2. Northern blot analysis revealed CRLF2 mRNA in liver, kidney, heart, and skeletal muscle. The fetal liver also expresses CRLF2 t ranscripts. The gene for CRLF2 was mapped to the pseudoautosomal region, Xp 22.3 and Yp11.3 by FISH analysis, a region where genes encoding the IL-3 re ceptor alpha and the GM-CSF receptor a chains are also located. The biologi cal function of this newly identified receptor is now under investigation. Copyright (C) 2001 S. Karger AG, Basel.