Leaves of mistletoe (Viscum albumL)contain three toxic lectins (type 2 ribosome-inactivating proteins) MLI, MLII, and MLIII, differing in molecular mass and carbohydrate specificity. Clones, containing sequences of three gene vari-ants designatedml1p, ml2p,andml3p, were obtained using PCRamplification fromcDNAand frommistletoe genomic DNA. The quantitative ratio of theml1p, ml2p,andml3p genes in genomic DNA was found to be : 1 : 4, respectively, whereas the ratio of their mRNA was 50 : 10 : 1
