A NOVEL LECTIN FROM SARCOPHAGA - ITS PURIFICATION, CHARACTERIZATION, AND CDNA CLONING

A novel C-type lectin that agglutinates rabbit red cells was purified from NIH-Sape-4 cells derived from the flesh fly (Sarcophaga peregrina ), and its cDNA was isolated. This lectin, named granulocytin, appeare d to be a trimer of a 20-kDa subunit consisting of 151 amino acid resi dues. The gene for granulocytin was activated in third instar larvae, and its expression was enhanced when the larval body wall was injured. In third instar larvae, granulocytin was found to be synthesized by h emocytes and secreted into the hemolymph. The molecular mass and gene expression patterns of granulocytin were very similar to those of Dros ophila lectin that we reported previously (Haq, S., Kubo, T., Kurata, S., Robayashi, A., and Natori, S. (1996) J. Biol. Chem. 271, 20213-202 18), However, these two lectins showed amino acid identities of 20% at most, and no significant hapten sugar for granulocytin was identified .