Seed storage protein. Expressed in seed (at protein level). Proteolytically cleaved. Causes an allergic reaction in human. Binds to IgE of patients allergic to walnuts (PubMed:10589017, PubMed:30054513, PubMed:21883278, PubMed:22042002, PubMed:25772597). Binds to IgE of patients allergic to peanuts (PubMed:21883278, PubMed:22042002). Recombinant protein binds to IgE in 60% of the 15 patients tested allergic to walnuts (PubMed:10589017). Natural protein binds to IgE in 67% of the 6 patients tested allergic to peanuts and/or walnuts (PubMed:21883278). Binds to IgE in 53% of the 17 patients tested allergic to walnuts. Provokes CD4(+) T-cell responses. The central memory CD4(+) T-cells are the most prevalent phenotype detected in the peripheral blood of the patients. T-helper 2 (Th2) cells are prominent among the terminal effector T-cells, but T-helper 17 (Th17) and Th2/Th17 cells are also detected (PubMed:25772597). Belongs to the 7S seed storage protein family. It is uncertain whether cleavage occurs at Arg-172 or Glu-173.