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Old 04-01-2010
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Default ALS and superoxide dismutase gene SOD1

Approximately 10% of the patients with familial amyotrophic lateral sclerosis have an autosomal dominant mutation in copper/zinc superoxide dismutase gene SOD1. one therapy unde investigation for treatment is hammerhead ribozyme. which of the following best describes the mechanism by which a hammerhead ribozyme would be expected to treat ALS?

A. Ribozyme mediated degradation of mutant SOD1 mRNA
B. Ribozyme mediated destruction of mutant SOD1 gene
C. Ribozyme mediated inhibition of mutant SOD1 splicing
D. Ribozyme mediated inhibition of translation of mutant SOD1 mRNA
E. Ribozyme mediated inhibition of transcription from mutated SOD1 gene
F. Ribozyme mediated targeting of mutant SOD1 protein for destruction by the proteosome
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Old 04-01-2010
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I think it will work on the mRNA itself so I choose option A, but am not sure
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Old 04-01-2010
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hammerhead ribozyme breaks substrate strand of RNA. So A.
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Old 04-01-2010
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yes guys its A
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Old 04-01-2010
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explain me how it works??? i gotta confused on this question
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Old 04-01-2010
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Default i also think that the answer should be choice A

but i don't certain about that answer please kindly explain me about the mechanism of interaction
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Old 04-01-2010
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I think the idea here is that hammerhead ribozyme works on the RNA molecule itself. Only Choice A is presenting a direct action on an RNA molecule.
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Old 04-01-2010
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main topic in wikipedia http://en.wikipedia.org/wiki/Hammerhead_ribozyme

Short version: self-cleaved RNA. In the natural state - ss RNA and in the absence of protein enzymes - autocatalitic. The hammerhead ribozyme carries out a very simple chemical reaction that results in the breakage of the substrate strand of RNA, specifically at C17.

Just ribozyme - is ribonucleic acid enzyme or RNA enzyme or catalytic RNA. They catalyze hydrolysis of own phosphodiester bonds or in other RNA. So hammerhead is distractor
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Old 04-01-2010
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Does anybody have a hint whether Dicer & Drosha are considered ribozymes?
(Dicer & Drosha are considered potential therapeutic targets in ovarian Ca).
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