CLONING AND CHROMOSOMAL MAPPING OF AN ORPHAN CHEMOKINE RECEPTOR - MOUSE RDC1

Degenerate RT-PCR was used to identify a new seven-transmembrane-spann ing receptor expressed in astrocytes. A receptor, termed RDC1, display ing the characteristic structural features of a chemokine receptor was cloned. The predicted 362-amino-acid sequence displayed 92% and 91% s imilarity to the human and dog orphan receptor RDC1, respectively. In addition, RDC1 shares 43% amino acid similarity to rabbit and mouse CX CR2. Transcripts of RDC1 were found in astrocytes, heart, kidney, the mesangial tumor line MES-13, spleen, and neutrophils by means of north ern blot. Using linkage analysis of interspecies backcross mice, we lo calized to chromosome 1 the genes for mouse CXCR2, CXCR4, and RDC1. Mo use RDC1 is linked to and lies between the genes for the mouse CXC che mokine receptors CXCR2 and CXCR4. The combined data of chromosomal loc ation and sequence similarity suggest that RDC1 is an orphan CXC chemo kine receptor.