Riva A, Mazzucchelli R, Morelli P, Lippi M, Galli M; International Conference on AIDS.
Int Conf AIDS. 2000 Jul 9-14; 13: abstract no. TuPpA1217.
A. Riva, University of Milan, via G. B. Grassi 74, 20157 Milan, Italy, Tel.: +0039-02-39042210, Fax: +0039-02-3560805, E-mail: a.riva@mailserver.unimi.it
Background: The human CCR3 is a seven-transmembrane-domain G protein-coupled receptor expressed on several haematopoietic cells, microglial cells and subpopulations of neurons. HIV-1 entry into target cells is mediated through a complex interaction between the viral envelope and specific cellular receptors. CCR3 is a coreceptor for HIV-1 cell entry. Methods and Results: The CCR3 gene was isolated from a human genomic library and a 2.1 kb fragment containing the 5, region subcloned into pGL3 reporter vector. 2,100 nucleotides were sequenced upstream of the major transcriptional start sites.CCR3-pGL3 constructs containing approximately 380, 680, 980, 1,200 and 1,500 nucleotides upstream of the major start sites were made. Human B, T and monocytoid cell lines were transiently transfected with the CCR3-pGL3 constructs and lucipherase activity was measured 48 hours later. An 18 fold induction of lucipherase activity over the background was observed in U937 cells with the 980 bp construct and a 14 fold with the 1,200 bp construct, however all the other constructs were inactive; the 980 bp and the 1,200 bp constructs displayed similar levels of activity in Jurkat and HS-Sultan cells. The treatment of U937 cells with IL-2 24 hours after transfection determined a 50% increase in the lucipherase activity of the 980 and of the 1,200 bp constructs compared to untreated cells. Conclusions: These results evidence that between the nucleotides 680 and 1,200 of CCR3 promoter there are elements which can direct high levels of transcription in haematopoietic cells. The dramatic decrease of lucipherase activity beyond 1,200 suggests the presence of negative regulatory elements in that region.The increase of activity induced by IL-2 in U937 cells suggests the presence of STATS binding sequences in the CCR3 promoter; the potential regulation of CCR3 expression by IL-2 might have important implications in HIV-1 infected patients treated with antiretroviral therapy and recombinant IL-2.
Publication Types:
Keywords:
- Base Sequence
- Carrier Proteins
- Cell Line
- DNA Primers
- Genomic Library
- Humans
- Interleukin-2
- Promoter Regions (Genetics)
- Transcription Factors
- Transcription, Genetic
- Transfection
- analysis
- genetics
Other ID:
UI: 102238825
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