Ribosome inactivating protein

Bhatia, N., McDonald, K. A., Jackman, A. P., and Dandekar, A. M, A simplified procedure for the purification of trichosanthin (a type 1 ribosome inactivating protein) from Trichosanthes kirilowii root tubers, Prot. Purif. Expression, 7, 143, 1996. 

Lambert, J.M., Blattler, W.A., McIntyre, G.D., Golmacher, V.S., and Scott Jr., C.F. (1988) Immunotoxins containing single chain ribosome-inactivating proteins. In Immunotoxins (A.E. Frankel, ed.), p. 175. Kluwer, Boston. 

The antileukemic efficacy of an immunotoxin composed of a monoclonal anti-Thy-1 antibody disulfide linked to the ribosome-inactivating protein gelonin. Cancer Immunol. Immunother. 25, 31. 

P = constitutive promoter, tetR = TETrepressor gene,TETR = TET repressor protein, tetO = TET operator sequence, = tetracycline, ere/CRE = Cre recombinase gene/protein, PLEA = late embryogenesis abundant promoter, RIP = gene for ribosome inactivating protein, shaded blocks are loxP sites in orientation shown by solid triangle. After [48]... 

Delayed-action cytotoxins that inhibits protein synthesis (ribosomal inactivating protein). They are obtained from the seed of the Jequirity beans plant (Abrus precatorius). Typically yellowish-white powders that are insoluble in distilled water but soluble in salt water. They are fairly heat stable. 

Cytotoxin that inhibits protein synthesis (ribosomal inactivating protein). It is obtained from the roots of Adenia digitata plant. 

Delayed-action cytotoxin that inhibits protein synthesis (ribosomal inactivating protein) that is obtained from castor beans (Ricinus communis). Waste from production of castor oil contains about 5% ricin by weight. It is a white powder that is soluble in water and relatively heat stable. Aqueous solutions are resistant to chlorine at 10 ppm. It is persistent in the environment. 

BOX 29-A THE DIPHTHERIA TOXIN AND OTHER RIBOSOME-INACTIVATING PROTEINS... 

Lambert, J. M., Senter, P. D., Yau-Young, A., Blattler, W. A., and Goldmacher, V.S. (1985) Purified immunotoxins that are reactive with human lymphoid cells monoclonal antibodies conjugated to the ribosome-inactivating proteins gelonin and the pokeweed antiviral proteins./. Biol. Chem. 260,12035—12041. 

Scott, C. J., Jr., Goldmacher, V. S., Lambert, J. M., Chari, R. V., Bolender, S., Gauthier, M. N., and Blattler, W. A. (1987) The antileukemic efficacy of an immunotoxin composed of a monoclonal anti-Thy-1 antibody disulfide linked to the ribosome-inactivating protein gel-onin. Cancer Immunol. Immunother. 25, 31. 

Barbieri, L., Battelli, M. G., and Stiipe, F. (1993) Ribosome-inactivating proteins from plants. Biochim. Biophys. Acta 1154, 237-282. 

Fig. 2. Removal of tritin from embryos. Extracts were prepared from unwashed or washed embryos (A) and the depurination assay was performed (B). Translation mixtures prepared with the extract from unwashed embryos were incubated for 0, 1, 2, 3, 4 h (lanes 1-5, respectively) mixtures with washed embryos were incubated for 0, 2, 4 h (lanes 10-12, respectively). Isolated RNA was treated with acid/aniline, and then separated on 4.5% polyacrylamide gels. Additionally, RNA was directly extracted from embryos with guanidine isothiocyanate-phenol and analyzed before (lane 7) and after (lane 8) treatment with acid/aniline. For the fragment marker, incubation was carried out in the presence of gypsophilin, a highly active ribosome-inactivating protein from Gypsophila elegance the arrow indicates the aniline-induced fragment.

Hirao, I., Madin, K., Endo, Y., Yokoyama, S., and Ellington, A. D. (2000) RNA aptamers that bind to and inhibit the ribosome-inactivating protein, pepocin. J. Biol. Chem. 275, 4943-4948. 

Examination of genotoxicity of pharmaceuticals is required to assess the interaction of the drug with DNA. These studies are generally not applicable to immunotoxins. Unlike chemotherapeutics that cause cell death through DNA interaction, immunotoxins mediate cell death by preventing protein synthesis. However, immunotoxins use a linker to connect the toxin to the antibody that may need to be examined if it is an organic linker and has the ability to bind DNA (per ICH S6). The majority of immunotoxins use either a nonreducible thioether linker for intact toxins or a disulfide bond for A chains and ribosome-inactivating proteins and do not interact with DNA. 

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