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In RNA viruses with a single-stranded genome, this RNA can be positive or negative sense. Positive sense RNA is directly translatable by a ribosome, while a negative strand RNA cannot be directly translated and therefore non-infectious. It either has to be converted to a positive strand RNA with the help of an RdRP (RNA-dependent RNA polymerase, carried in ...


7

The answer to Question 1 is: The ribonucleases responsible for digesting removed intron RNA do not recognize the miRNA as such. They are unable to digest it because (or to the extent that) it assumes a double-stranded structure, as they are specific for single-stranded RNA. The answer to Question 2 is briefly: By the same mechanism as the many microRNAs ...


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Meng et al. actually give their explanation in the first paragraph of their results section. The main reasons for their claim are that they did not detect any labeling with 4SU or EU and that both analogs suppress bacterial growth. Also they raise the issue with the naturally occurring 4SU in tRNAs. Aiming to develop nucleoside analogs compatible with ...


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There are naturally occurring RNAs that contain a NAD "cap" at 5' end (Bird et al., 2018; Wang et al., 2019). I could not find any papers on natural RNAs with nicotinamide or flavin as a regular base. However, a study with synthetic oligonucleotides reports that NAD containing oligonucleotides can form stable triplex structures (Göckel & ...


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Note - This answer only covers the comparison of rA-dT (RNA:DNA) and rA-rU (RNA:RNA) duplexes, and not more exotic options involving deoxyuridine (dU) and ribothymidine (m5U). I can think of three possible reasons why oligo-dT may be preferred over oligo-rU for poly(A) hybridization and mRNA capture: The rA-dT duplex is more stable than the rA-rU duplex, ...


4

Yes is the short answer. These are known as silencing RNAs or interfering RNAs The longer answer is You would need much more RNA than you could easily administer to the epithelial cells of the mucosa and other tissues that viruses like SARS-CoV-2 infect, so as to cover each individual cell. In addition you would need to be able to deliver it to those tissues ...


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If I understand your question and graph correctly, your Y-axis is log(x/REF), where REF is some external standard. Your "Ref" on the x-axis you expect to be the same as REF, so that log(Ref/REF) "should be" zero, but you find it is not. However, it looks like the mean(log(Ref/REF)) is still approximately zero. This is what I would expect: ...


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N1-methyl-pseudouridine occurs naturally in the tRNAs of most archaea. It replaces the ribothymidine found in the TΨC-loop of eubacterial and eukaryotic tRNAs. Although the enzyme responsible for the conversion of uridine to pseudouridine has been known for some time, it is only relatively recently (2012) that the gene for the methylation of the ...


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In attempting to answer questions about protein structure, the first port of call (which one might expect the questioner to have also visited) is the Protein Data Bank — the global repository of such structures. There one can search for RNA Polymerase II CTD, look for complexes with other proteins, find recent publications in which they are reported, and ...


2

It is entirely possible that different cell-lines express the same genes at drastically different levels. The proteinatlas provides data and analyses on differences between certain tissues or cell types / cell-lines. If your cells are of the same line/tissue, then they might still differ dependent on the cell-cycle, age and external factors. There are ...


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There would seem to be two possibilities: The enzyme has differential specificity for different substrate NDPs. or The deciding factor is the relative concentrations of the different NDPs in the cell. Although the structure of the enzyme has been determined there do not appear to be any studies that would distinguish between these possibilities. This is ...


1

RNAi can happen in the nucleus as well. This is better documented in C.elegans but there are some references supporting nuclear RNAi in mammalian cells too: https://doi.org/10.1073/pnas.1707440114 https://doi.org/10.1016/j.celrep.2013.12.013 https://doi.org/10.1093/nar/gkv1305


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From Off-Target In Vitro Profiling Demonstrates that Remdesivir Is a Highly Selective Antiviral Agent: Overall, the cellular and biochemical assays demonstrated a low potential for RDV to elicit off-target toxicity, including mitochondria-specific toxicity, consistent with the reported clinical safety profile. This isn't a very complete answer, but the ...


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According to the Labome article "siRNAs and shRNAs: Tools for Protein Knockdown by Gene Silencing" siRNA does stand for small interfering RNA. siRNA is used to silence genes via mRNA degredation: NA interference (RNAi) is the process by which the expression of a target gene is effectively silenced or knocked down by the selective inactivation of ...


1

Interestingly, there's recent news we may all have some reverse transcriptase activity and in some people it leads to serious disease. The specificity of that reverse transcription is not yet known, but HIV reverse transcriptase is going to require a primer binding site - basically some lysine tRNA sequence - to get started. Of course, with low odds, there ...


1

The human body basically does this on its own. We express various RNAses, some of which appear to have specific antiviral or bactericidal roles. (This appears to be due to both RNAse activity and to biochemical properties of the proteins independent of RNA digestion)


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