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RNA splicing refers to a certain kind of RNA processing mechanism which leads to the excision and exclusion of some regions of the primary transcript. You should note that this is not the only method by which such a thing can happen; Endo-ribonucleases can clip the ends of the transcript and this happens in the case of tRNA-processing. But as "splicing" ...


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There is a vast amount of knowledge regarding the composition and function of mitochondria. You might want to head to http://www.pubmed.com and search reviews on mitochondria and S.cerevisiae as keywords. You might also want to check sites such as http://www.mitoproteome.org/ that are dedicated to this kind of information.


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RNA splicing begins with assembly of helper proteins at the intron/exon borders. These splicing factors act as beacons to guide small nuclear ribo proteins to form a splicing machine, called the spliceosome. These animation is showing this happening in real time. see> ...


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In short, no, molecules aren't synthesised that way. This is because the common atoms that in biomolecules (C, O, H, N, P) don't occur as individual atoms in nature and it would be extremely difficult (and unnecessary) to keep them in a single-atom state ready for assembly into a molecule in some way. However, chemists are able to synthesise almost any kind ...


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Yes, the difference is "only" in the 3D structure. This makes some differences when proteins change their shape, antibodies which recognize conformational epitopes are usually not well suited for lab work, as proteins are often denaturized here. The different epitopes are also called linear epitopes (for the sequencial) and discontinous epitope (for the ...


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There are literally millions of biomolecules. Some of them we know the structures and chemical properties of others we know nothing about. I'm going to focus on sugars. It would be too broad a question probably even to list all biomolecules, much less describe how their chemical synthesis would be performed. The good news is that industrial ...


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Absolutely, the two I've had the most success are working with a radiolabeled and a fluorescently labeled version of the drug. Many drugs autofluoresce as well and this can be easily tracked. When it's labeled as mentioned above microscopy or a luminometer, spectrophomoter or a scintillation counter can evaluate fractions or whole cells, or purified ...


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There are many mechanisms of receptor down-regulation, including internalisation and degradation e.g for the epidermal growth factor receptor and uncoupling via post-translational modifcation e.g. for G protein-coupled receptors. In the case of opioid receptors there is emerging evidence that down-regulation is achieved, at least in part, by ...


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This is a tough topic, have a look at the following references and see, if they can help you: Structural modelling and dynamics of proteins for insights into drug interactions. Ligand entry pathways in the ligand binding domain of PPARγ receptor Pathway and mechanism of drug binding to G-protein-coupled receptors Molecular Dynamic Simulation and Inhibitor ...


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Let's do your second one first, you want to find the rate of binding: Yes you are right you need to calculate for km I think I found the paper that ties temp into the reaction rate: statistical approach called response surface methodology (RSM) is used for the prediction of the kinetic constants of glucose oxidase (GOx) as a function of reaction ...


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If your looking at transcription then your talking about RNA POLYMERASE. And there are many variants. Here's a good Nature paper that discusses temperature and RNA Pol http://www.nature.com/ncomms/journal/v1/n6/full/ncomms1076.html And another: http://www.ncbi.nlm.nih.gov/m/pubmed/12729734/ I couldn't get full access to this JBC paper but I think the ...


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The units here are relative units of intensity. There may be about a picomole of probes on a microarray spot, but the units of intensity are not scaled to the precise concentration of DNA on the spot. There are many variables which make exact measurements of intensity difficult to translate into the number of RNA bound to a spot. The main one is ...


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With this method you want to identify proteins on cancer cells which are immunogenic so you can use them to boost an immune response against the cancer cells. To do so, you extract the complete mRNA from a cancer. These mRNAs represent all the genes which this cancers expresses (which then also contains the immunogenic proteins). These mRNAs are cloned into ...


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This sounds straightforward when thinking about it but finding hard evidence is not really easy. As this is too long for a comment, I have to put it in as an answer. Just a few thoughts: All enzymatic reactions are of course temperature dependent and usually have a temperature optimum at the specific living temperatures. For yeast this is around 27°C, for ...


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Interesting question. The GC-content seems to evolve over time and it also seems that the GC-content of coding regions is higher than for the surrounding non-coding regions (see reference 1). If there is a specific function for this higher GC-content or not is (if I understand this right) debated among the groups which do research in this field. Have a look ...


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The paratope is the part of an antibody that binds the epitope on the antigen. The CDRs (heavy chain CDRs shown below) are part of the structure of the variable domain, and contain the hypervariable regions that bind to the epitope. The actual paratope is within the hypervariable regions, which are within the CDRs - the paratope is not necessarily made ...


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First, degeneracy in a basic sense refers to redundancy of the codons in the genetic code. For example, the amino acid proline is coded for by one of four codons: CCA, CCC, CCG and CCU. The third codon position (the third letter in each group of three) is called four-fold degenerate because it can change without affecting the coding for proline. ...


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I'm assuming you mean DNA sequencing (excluding things like RNA-seq). Is Sanger sequencing the first generation? From Metzker 2010: The automated Sanger method is considered as a "first-generation" technology Some of the technology that was in development when this review was written is no longer in development, but this is still an excellent review ...


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In an RNA microarray, a hybridization event between a probe and target sequence would indicate a presence of the transcript within the sample. The probes are oligonucleotide sequences found on the microarray chip. The target sequences are representative of the entire transcriptome. The targets are found within your biological sample and have gone through ...


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RNA usually has pretty complex structures. What causes the problem with NMR however is that large RNAs, such as mRNAs, don't have 1 structure, they have a population of possible secondary structures, and even if small parts of the RNA always have the same local structure, the overall molecule will occupy a variety of forms. The NMR will see a population of ...


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Short answer - you will need to use a nonionic detergent. These will dissolve lipid membranes but leave most protein complexes intact, and many proteins in active form. However there are many of these available and finding the right one for a particular job is a black art. The usual approach is to start off with something widely-used and not too expensive ...


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If you have an antigen (something foreign for the immune system, for example a virus or bacteria) this consists of many different epitopes (immunogenic regions), as shown in the figure below (from the German Wikipedia, Antikörper means antibodies). The antigens are taken up by special cells of the immune system and processed to get small peptides: To ...


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I think the reason you are having trouble discerning the statement is because it doesn't really make much sense, nor is it in my opinion sufficiently explained in the paper. The sentences preceding the it give a little explanation as to what the author may be getting at: So far, 1500 allergenic structures have been identified. Online allergen databases ...


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I actually doubt that the pectinase has such a broad pH range in which it works optimally. Searching the web I found two figures which support my doubts: The first is from an article ("Immobilization of pectinase by adsorption on an alginate-coated chitin support") which compares the activity of native and immobilized pectinase under different ...


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As a simplified response: Propensity score is used to predict protein secondary structure. It is derived from looking at the aa residue of the accessible surface of the protein and also the interface which enables interactions between other proteins. The equation is as follows: Propensity= [probability of the residue in the interface / probability of the ...


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Check this technique called Chromosome Conformation Capture (3C). Its variants exist such as 4C, Hi-C etc. Basically, the principle of this technique is based on the physical interaction between the enhancer and promoter that is bridged by a transcriptional modulator(protein). The chromatin is crosslinked DNA is sheared The protein is pulled down ...


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Try rinsing the blot in TBS or PBS before treating. Shake it try and place on level dry surface. When I pour the a chemo reagent on there I just pour enough so the surface tension keeps the fluid on the paper not allowing it to run off. Other possibilities I see could be in your transfer. The temp could not be uniform in the buffer


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Well usually in an ECL kit, one of the reagents is the substrate and the other one is hydrogen peroxide, which activates the substrate for breakdown using the HRP on your secondary antibody (Ab) so I genuinely doubt what you are seeing is the result of ratio difference. In order to make that conclusion you need to run your samples twice (on two separate ...


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I realize this question is about yeast, but I'm afraid that people may try to expand the answer to all systems, and beta galactosidase is not good for all systems, particularly for animal studies. I've seen too many gene therapy papers try to get away with using it. Beta galactosidase is not a good reporter gene for in vivo gene delivery studies. There is ...


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Lets define the nomenclature first: An antigen is a large structure (protein, virus, bacteria and so an) which is recognized by the immune system as foreign. The word antigen derives from the abbreviation ANTIbody GENerator. Exposure of our immune system to an antigen results in an immune response and the generation of many antibodies. An epitope is a small ...


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The primer is an universal recruiter, for all DNA polymerases, bringing them to the DNA template. You must have both strands in place for a DNA polymerase to stop by. Moreover, the catalytic activity of all the polymerases requires a preexistent 3' end on the growing strand. You must have a 3' free end near a template, for a DNA polymerase to act. (A far ...



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