RT Conference Proceedings
T1 Structural basis of the allergenicity to strawberries due to Fra a 1.02
A1 Orozco-Navarrete, Begoña
A1 Dupeux, Florine
A1 Pott, Delphine
A1 Casañal, Ana
A1 Garrido-Arandia, María
A1 Díaz-Perales, Araceli
A1 Merchante-Berg, Catharina
A1 Márquez, José A.
A1 Valpuesta-Fernández, Victoriano
K1 Fresas
AB Strawberry fruits are highly valued due to their flavor, aroma, and benefits for human health. Despite this, 30% of the population with food hypersensitivity also shows adverse reactions to strawberry (Franz-Oberdorf et al, 2016). The FaFra a 1 protein family, homologs of the major birch pollen allergen Bet v 1, is involved in this allergenicity to strawberry. By RNAseq we have identified transcripts for 18 members of the FaFra a 1 family (from 1.01 to 1.18) in strawberry fruits. Although expressed in all tissuesanalyzed, each family member presents a unique pattern of expression, which suggests functional specialization for each FaFra a 1 protein. FaFra a 1.02 (Fra2 from now on) is the most expressed one in red fruits and is also the most allergenic among the family members tested (Muñoz et al. 2010; Franz- Oberdorf et al, 2016). In order to understand the molecular bases of this allergenicity we crystalized Fra2 and obtained its structure by X-ray diffraction. Fra2 showed a very high structural homology to Bet v 1, and we asked whether the two proteins were recognized by the immune system in a similar way. For this, we generated five different mutant versions of Fra2 in sites described as important for allergenicity in Bet v 1 (Fernandes et al, 2016), and studied their potential allergenicity as well as their crystal structures. Three of the mutants had substitutions in loop 4 (E46R, D48R, E46/48A) and the other two facing the cavity (A141F and Q64W). Compared to Fra2, all the mutants showed a significant reduction in theircapacity to be recognized by the serum of patients with allergies to Bet v 1, and their crystal structures revealed conformational changes in the Bet v 1- IgG interaction sites. Together, these results support that Fra2 and Bet v 1 have similar allergenic determinants We hope this research will aid in understanding how human IgGs interact with Fra2 and might help in the development of new cultivars with a lesser allergenic potential.
YR 2018
FD 2018-07-13
LK https://hdl.handle.net/10630/16269
UL https://hdl.handle.net/10630/16269
LA eng
NO Grants BIO2013-44199R andBES-2014-068723 (MINECO). The authors also acknowledge the support by the Plan Propiofrom University of Malaga, Campus de Excelencia Internacional de Andalucía.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026