Molecular cloning and characterization of an allergen from Persian melon - 25/08/11
Abstract |
Rationale |
Profilin is a panallergen that is recognized by IgE from about 20% of birch pollen- and plant food-allergic patients. Most of the melon-allergic patients (more than 70 percent) presented specific IgEantibodies to 14.4 Kda protein in melon extract that could be attributed to profilin.
Methods |
To characterize allergenic component of the melon at the molecular level, this study was aimed at the cloning of melon major allergen cDNA. The IgE-binding component was isolated from melon by cation exchange FPLC and a purification step on poly-L-proline 4BSepharose. Cloning of melon profilin was performed by reverse transcription-PCR using degenerated primers. 5' and 3' RACE methods were carried out for the identification of the unknown 5'-end and 3'-end of the cDNA.
Results |
Four isoforms of profilin identified that significant differences were noted in the non-coding regions, whereas coding sequence in one of them only showed a variation in position 54. Coding sequences of all isoforms (AY292385, AY292386, AY292385) had a length of 394 bp corresponding to 131 amino acid residues and a predicted isoelectric point of 4.46. The deduced amino acid sequence of the corresponding protein showed high identity with other plant profilins (71-84%) recently described as allergens.
Conclusions |
Profilin is an important allergenic compound in melon and shows high homology to pollens profilin. Pollenosis and associated allergies to melon can therefore partly be explained by the cross-reactivity between homologous profilins.
Le texte complet de cet article est disponible en PDF.![]() | Funding: Mashhad University of Medical Sciences, Indoor Biotechnologie |
Vol 113 - N° 2S
P. S299 - février 2004 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.
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