Molecular cloning and characterization of a novel lectin gene from Lycoris radiata

By the use of RACE-PCR with RNA extracted from Lycoris radiata young leaves, the full-length cDNA of L. radiata agglutinin (LRA) was cloned. The full-length cDNA of LRA was 669 bp and contained a 477 bp open reading frame encoding a 158 amino acid protein. Through comparative analysis of Ira gene and its deduced amino acid sequence with those of other Amaryllidaceae species, it was found that Ira encoded a precursor lectin with signal peptide. LRA was a mannose-binding lectin with three mannose-binding boxes like lectins from other Amaryllidaceae species. Southern blot analysis of genomic DNA revealed that Ira belonged to a low copy gene family. Northern blot analysis demonstrated that Ira constitutively expressed in various plant tissues including leaf, root, stem and inflorescence, and highly expressed in the inflorescence.