Mechanism of action of ricin and related toxic lectins on eukaryotic ribosomes.
نویسندگان
چکیده
We have studied on the mechanism of ricin action on rat liver ribosomes and present evidence which shows that the toxin inactivates ribosomes by modifying two bases at positions G-4323 and A-4324 of 28S rRNA adjacent to alpha-sarcin cleavage site. Further results showing that those phosphodiester bonds are very labile against alkaline digestion and aniline-treatment strongly suggest that these purine bases are removed by N-glycosidase activity of the toxin. In parallel, we also present evidence showing that abrin and modeccin have the same activity on eukaryotic ribosomes as ricin does.
منابع مشابه
RNA N-glycosidase activity of ricin A-chain. Mechanism of action of the toxic lectin ricin on eukaryotic ribosomes.
The modification reaction of 28 S rRNA in eukaryotic ribosomes by ricin A-chain was characterized. To examine whether ricin A-chain release any bases from 28 S rRNA, rat liver ribosomes were incubated with a catalytic amount of the toxin, and a fraction containing free bases and nucleosides was prepared from the postribosomal fraction of the reaction mixture by means of ion-exchange column chro...
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ورودعنوان ژورنال:
- Nucleic acids symposium series
دوره 17 شماره
صفحات -
تاریخ انتشار 1986