Cloning and functional characterization of the 5'-flanking region of the human monocyte chemoattractant protein-1 receptor (CCR2) gene. Essential role of 5'-untranslated region in tissue-specific expression.
The human monocyte chemoattractant protein-1 receptor designated hCCR2 is an essential co-receptor in cell entry by the human immunodeficiency virus as well as a receptor for monocyte chemoattractant protein-1, a member of the family of C-C chemokines that mediate monocyte chemotaxis. To elucidate the molecular mechanisms underlying the transcriptional regulation of hCCR2, we cloned and sequenced the hCCR2 gene; it was approximately 8 kilobase pairs in length and consisted of three exons divided by two introns. In the 5'-flanking region, there were the typical mammalian promoter consensus elements, a CAAT box and a TATA box, resulting in a single transcription initiation site. In addition, we found clustered tissue-specific cis-regulatory elements such as GATA consensus sequences, Oct-1 binding sequences, and CAAT/enhancer-binding protein binding sequences. Luciferase assays with various promoter deletions and gel mobility shift assays indicated that three cis-regulatory elements located within the region from -89 to +118 are required for basal activity in THP-1 cells. One element is an octamer sequence 36-base pair upstream from the TATA box; it binds mainly to Oct-1 and is capable of increasing transcriptional activity. The other two elements, which are tandem recognition sites of the CAAT/enhancer-binding protein family, are located in the 5'-untranslated region and account for the transcriptional activation as well as the tissue specificity of hCCR2.
Yamamoto
K
K
Department of Neurosurgery, Kumamoto University School of Medicine, Kumamoto 860-8556, Japan.
Takeshima
H
H
Hamada
K
K
Nakao
M
M
Kino
T
T
Nishi
T
T
Kochi
M
M
Kuratsu
J
J
Yoshimura
T
T
Ushio
Y
Y
D020121:5' Untranslated Regions; D017398:Alternative Splicing; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D018932:Chemokine CCL2 / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D004268:DNA-Binding Proteins / Q000378:metabolism; D051863:Host Cell Factor C1; D006801:Humans; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D050811:Octamer Transcription Factor-1; D011485:Protein Binding; D054390:Receptors, CCR2; D019707:Receptors, Chemokine / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured