Structure, genomic organization, and expression of the human interleukin-8 receptor B gene.
Two distinct receptors for the chemoattractant interleukin-8 (designated IL-8RA and -B) have been cloned recently. The receptors are expressed almost exclusively on neutrophils and myelomonocytic cell lines. In an attempt to understand the tissue-specific expression and to identify transcriptional regulatory elements we have cloned, sequenced, and characterized the human IL-8RB gene. The gene consists of 3 exons, interrupted by two introns of 3 and 5.4 kilobases (kb). A 1065-base pair open reading frame is encoded entirely in the third exon. A 1.4-kb 3'-untranslated region contains clustered AU-rich elements, similar to those described for genes regulated by altering mRNA stability. The start site of transcription was mapped by a modified rapid amplification of cDNA ends technique and revealed an unexpectedly long 5'-untranslated region of 423 base pairs. A TATA box equivalent was found in the 5'-flanking region 20 nucleotides upstream of the start of the first exon. The promoter was separated from the ATG-initiation codon by 8.75 kb. Comparison of the IL-8RB promoter with the promoter region of the receptor for another chemoattractant ligand, the bacterial peptide f-Met-Leu-Phe, revealed 3 novel but conserved motifs occupying similar positions. The immediate 5'-flanking region was GC-rich with 3 SP-1-like and 2 AP-2 sites identified in close proximity to the transcription start site. This essential promoter region was found to be responsible for constitutive expression, inducible by granulocyte colony-stimulating factor and controlled by silencer elements located further upstream between positions -779 and -118.
Sprenger
H
H
Laboratory of Molecular Immunoregulation, National Cancer Institute, Frederick Cancer Research and Development Center, Maryland 21702.
Lloyd
A R
AR
Lautens
L L
LL
Bonner
T I
TI
Kelvin
D J
DJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D016384:Consensus Sequence; D005091:Exons; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000187:drug effects; D015698:Genomic Library; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D015186:Hominidae / Q000235:genetics*; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000096:biosynthesis / Q000737:chemistry; D018123:Receptors, Interleukin / Q000096:biosynthesis* / Q000235:genetics*; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D016385:TATA Box; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D012333:RNA, Messenger; D018123:Receptors, Interleukin; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B; D014409:Tumor Necrosis Factor-alpha; D016179:Granulocyte Colony-Stimulating Factor