Genomic organization of peanut allergen gene, Ara h 3.
Type 1 hypersensitivity to peanut proteins is a well-recognized health problem. Several peanut seed storage proteins have been identified as allergens. Ara h 3, a glycinin protein, is one of the important peanut allergens. Although amino acid and cDNA sequences are available for Ara h 3, there is not information at the genomic level. The objectives of this study were to isolate, sequence, and characterize the genomic clone of peanut allergen, Ara h 3. A peanut genomic library was screened, using two [32P] end-labeled oligonucleotide probes designed based on cDNA sequences of Ara h 3 and Ara h 4. Four positives lambda FIX II clones were obtained after four rounds of screenings. Digestion with Sac I resulted in two fragments of 1.5 and 10 kb hybridizing to the probes. Both fragments were subcloned into p-Bluescript vector and sequenced. The Ara h 3 gene spans 3.5 kb and consists of four exons, three introns, 5' and 3' flanking regions. The open reading frame is 2008 bp long and can encode a polypeptide of 538 amino acids residues. Sequences analogous to a TATA-box (TATAAAT), CAAT-box (AGGA), G-box (TCCTACGTGTCC) and several cis-elements were found in the promoter region. In the 3' downstream region, three polyadenylation signals (AATAAA) were identified.
Food Biotechnology Laboratory, Department of Food and Animal Sciences, P.O. Box 1628, Alabama A and M University, Normal AL 35762, USA.
Olga M
OM
Viquez
Koffi N
KN
Konan
Hortense W
HW
Dodo
D000485:Allergens / Q000235:genetics*; D052179:Antigens, Plant; D010367:Arachis / Q000276:immunology*; D001483:Base Sequence; D040461:Gene Components; D016678:Genome; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000276:immunology; D055314:Seed Storage Proteins; D017422:Sequence Analysis, DNA
D000485:Allergens; D052179:Antigens, Plant; D010940:Plant Proteins; D055314:Seed Storage Proteins; C118207:allergen Ara h3