<正>Objective: To explore the correlation between structure domains and functions of chemokine receptor CXCR4. Methods: After the establishment of wild type chemokine.receptor CXCR4 and CXCR2 expressing cell lines

5 CXCR4/CXCR2 chimeras

2 CXCR4 mutants were stably expressed on CHO cell line. Binding activities of all variants with the ligand

recombinant human SDF-1β

signal transduction ability after stimulation and their function as coreceptor for HIV-1 were studied with ligand-binding assay

Cytosensor/ microphysiometry and cell-cell reporter gene fusion assay. Results: Among all 7 changed CXCR4 receptors

3 chimeras （2444a

4442

4122）

and 1 mutant （CXCR4-Tr） bond with SDF-1β in varying degrees

of which only 2444a totally and CXCR4-Tr partially maintain signaling. All changed receptors except for 4222 could act as coreceptors for HIV-1 （LAI） in varying degrees. Conclusion: Several structure domains of CXCR4 are involved in the binding with SDF-1β

among which

N-terminal extracellular domain has h