The FcεRI couples the mast cell-surface binding of IgE and Ag to a complex series of intracellular events culminating in cell activation and degranulation. The α-chain of FcεRI constitutes the Ig-binding subunit of this heterotetrameric receptor, and is itself a member of the Ig gene superfamily. We have isolated a human genomic DNA clone containing the entire FcεRIα gene, and completely sequenced a region from 1257 bp 5′ of the transcription start site, to 513 bp 3′ of the last exon of the gene. As with the previously characterized rat and mouse genes, human FcεRIα consists of five exons and four introns, and spans 5889 bp of genomic DNA. The splice donor and acceptor sites deduced by comparison with the cDNA sequence corresponded exactly to the locations found in analogous rodent genes. By mapping the 5′ end of FcεRIα transcripts we found three major transcription initiation sites 24, 27, and 29 bp upstream of the ATG translation initiation codon. As well, several longer minor transcripts were seen, with a maximum of 60 nt of 5′-untranslated sequence. About 650 bp of DNA upstream of the ATG translation initiation codon were compared among human, rat, and mouse FcεRIα sequences in search of common motifs that might mediate conserved regulatory interactions with DNA binding proteins. A 172-bp region of the human FcεRIα 5′-flanking sequence was highly conserved in both rodent species. Further studies will be required to determine whether these or other sequences are involved in FcεRIα gene regulation.
|Original language||English (US)|
|Number of pages||9|
|Journal||Journal of Immunology|
|State||Published - Dec 1 1993|
ASJC Scopus subject areas