We have isolated and characterized a cDNA clone, Ory s 1, encoding a g
roup-1 allergen of rice pollen. The Ory s 1 protein shows significant
sequence identity to the major allergen of rye-grass pollen, Lo1 p 1.
RNA gel blot analysis shows that the Ory s I gene is expressed in matu
re anthers, but not in vegetative or other floral tissues tested. Sout
hern blot analysis indicates that this clone represents a member of a
small gene family in rice. Western blot analyses of total rice pollen
proteins with the group-1 allergen-specific monoclonal 3A2 and IgE ant
ibodies from grass pollen-allergic patients, revealed the presence of
cross-reactive antigenic and allergenic epitopes in Ory s 1.