Molecular cloning and characterization of a cDNA, CHEMR1, encoding a
chemokine receptor with a homology to the human C-C chemokine receptor,
CCR-4
BS Youn, SH Kim, MS Lyu, CA Kozak, DD Taub and BS Kwon
Department of Microbiology and Immunology, and Walther Oncology Center,
Indiana University School of Medicine, Indianapolis 46202-5120, USA.
Chemokines refer to a rapidly expanding family of small cytokines whose
primary function is recruitment of leukocytes to inflammatory sites. These
are known to bind to seven-transmembrane-domain containing receptors. A
cDNA clone, CHEMR1, resembling the typical G protein- coupled receptor, was
isolated from a mouse cytotoxic T-lymphocyte (CTL) library. Northern blot
analysis in mouse cell lines suggests that its expression is found in a
variety of cells, including T cells, B cells, and macrophages. The CHEMR1
gene Scya3r2 is a single-copy gene whose open reading frame may be in a
single exon and maps to the distal region of mouse Chr 9 where the mouse
macrophage inflammatory protein- 1alpha (MIP-1alpha) receptor gene Scya3r
and two related C-C chemokine receptor-like genes reside. Amino acid
sequence comparison shows that CHEMR1 is 84% identical to human CCR-4,
indicating that CHEMR1 is likely to be a mouse CCR-4. Binding assays using
125I-labeled C-C chemokines in mammalian cells indicated that CHEMR1 did
not bind MIP- 1alpha, RANTES, or MIP-1beta, whereas CCR-1 binds MIP-1alpha
and RANTES. Our result is different from the reported properties of human
CCR-4. This suggests that CHEMR1 may be a receptor for unidentified C-C
chemokine or a low-affinity receptor for MIP-1alpha.
Volume 89,
Issue 12,
pp. 4448-4460,
06/15/1997
Copyright © 1997 by The American Society of Hematology
