TISSUE-CULTURE OF ENDOD (PHYTOLACCA-DODECANDRA LHERIT) - GROWTH AND PRODUCTION OF RIBOSOME-INACTIVATING PROTEINS

Leaves and stems from endod (Phytolacca dodecandra L'Herit), known to produce the 29 kDa ribosome-inactivating protein (RIP) dodecandrin, we re initiated into tissue culture. Callus and suspension cultures were maintained on modified Murashige and Skoog medium plus 1.0 mg/l 2,4-di chlorophenoxyacetic acid. Six callus and two suspension cell lines wer e screened for dodecandrin production by western blots with affinity-p urified antiserum. Antiribosomal activity of culture extracts was test ed by in vitro translation assays. One suspension cell line was found to be free of immunoreactive proteins and a ribosome inhibitor. All ot her cell lines contain a ribosome inhibitor, although only two callus cell lines show detectable amounts of immunoreactive proteins at the s ame M(r) as dodecandrin. Other immuno-reactive proteins were detected in callus (M(r) 31000, 33000, 41000 and 43000) and in suspension cells (M(r) 23000 and approximately 43000), and may be ribosome inhibitors related to dodecandrin-either other RIPs or dodecandrin at various sta ges of processing.