Genomic cloning and characterization of a novel lectin gene from Zantedeschia aethiopica.

A new lectin gene was isolated by using genomic walker technology and revealed to encode a mannose-binding lectin. Analysis of a 2233 bp segment revealed a gene including a 1169 bp 5' flanking region, a 417 bp open reading frame (ORF) and a 649 bp 3' flanking region. There are two putative TATA boxes and eight possible CAAT boxes lie in the 5' flanking region. The ORF encodes a 15.1 kDa precursor, which contains a 24-amino acid signal peptide. One possible polyadenylation signal is found in the 3'-flanking region. No intron was detected within the region of genomic sequence corresponding to zaa (Zantedeschia aethiopica agglutinin) full-length cDNA, which is typical of other mannose-binding lectin gene that have been reported. The deduced amino acid sequence of the lectin gene coding region shares 49-54% homology with other known lectins. The cloning of this new lectin gene will allow us to further study its structure, expression and regulation mechanisms.