Ricin: Difference between revisions

The mechanism deployed by Ricin to gain entry to a host cell involves the poison's heterogenic properties. First, the toxin arranges itself in such a way where its B chain can easily interact with the host cells receptors, and once acknowledgement happens, the B chain can facilitate transport of the A chain into the cytoplasm<ref name="montfort" />. This association between the A and B chain is essential for toxicity<ref name="montfort" /> without it the Ricin would not be able to gain access to the cells organelles rendering it useless. Once the A chain gains entry into the cytosol its mechanism for attack of the [[Ribosome|ribosome]] is depurination of a single adenosine residue in a highly conserved portion within the large RNA of the cytoplasmic [[Large Ribosomal Subunit of Haloarcula|large ribosomal subunit]]<ref name="rapak" /> of eukaryotes; in human, the large cytoplasmic ribosomal RNA is called the 28S ribosomal RNA because of its sedimentation properties during ultracentrifugation. The nucleotide depurinated is located within a specific, conserved loop referred to as th <nowiki>'</nowiki>sarcin-ricin loop<nowiki>'</nowiki>; the loop is critical for binding [[elongation factors|elongation factors]] during [[Translation|translation]] of messenger RNA to protein <ref name="holmbergnygard">PMID: 8648651</ref>. Depurination of the single adenosine nucleotide by the toxin results in the inhibition of protein synthesis.