cDNA cloning, expression and primary structure of Par jI, a major allergen of Parietaria judaica pollen.

A 659 bp cDNA clone** coding for an allergen of Pj pollen has been isolated from a lambda gt11 library, and its DNA sequence determined. The cDNA insert showed an open reading frame of 429 bp coding for an allergenic protein of 14,866 Da and a deduced amino acid sequence containing 143 residues. The expressed recombinant protein represented the major allergen Par jI since it reacted with 95% of the sera from Pj-allergic patients (n = 22) and with two Par jI-specific monoclonal antibodies. No similarity with other known DNA and protein sequences has been detected.