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Different cancers divide at different rates. One way to qualitatively visualize this is observe hair loss in patients who are undergoing chemotherapy. Commonly, a drug like cisplatin will be administered which will cross-link DNA, inhibiting cell division by activating apoptosis. Tissues which are killed most readily by cisplatin are those which are dividing ...


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According to this paper (Yoav Soen et al. PLoS Biology 2003), peptide:MHC microarrays are a type of cellular microarray (a microarray designed to identify cell types; Wikipedia). These microarrays have attached a MHC molecule bound to a peptide, which allows them to work as artificial antigen presenting cells (APCs) that activate specific subpopulations of T ...


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hTAP refers to human TAP protein (reference). And how do you know that TAP refers to Transfer Associated Protein? I believe it stands for Transporter Associated with Antigen Processing (reference). Your facts are wrong which is why your question couldn't be answered.


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I made a quick sketch on the basis of the information you gave (this is not to scale): Aminoacid 5 (aa5) of the protein is on the outside, aa90 is inside the membrane. What we don't know here where the transmembrane part starts (directly with aa6 or later) and how it is organised (I indicated this as a transmembrane helix, but this can of course be ...


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Membrane proteins are usually drawn as topological digrams with two parallel horizontal lines representing the membrane. lines as 'extracellular' and below the lines as 'intracellular' for instance, but that is not what is being asked for here. Its not clear to me that the number of transmembrane spans are fully described, nor are the boundaries of the ...


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An expression vector is a (usually circular) piece of DNA which is able to replicate inside a (bacterial) cell independently of the genome. Vectors can be transferred between bacteria and can express proteins from their own DNA sequence. They are used to express proteins inside of bacterial cells which can subsequently be purified. In this case the sequence ...


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A haplotype is commonly defined as ...a group of genes within an organism that was inherited together from a single parent. -- Nature Scitable This definition of haplotype applies whether it is just a few genes or all of the genes on an entire chromosome$^1$. In the case of the major histocompatibility complex, it is a group of more than 200 genes on ...


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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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As stated in wiki "The major histocompatibility complex (MHC) is a set of cell surface molecules encoded by a large gene family in all vertebrates which controls a major part of the immune system. MHC molecules mediate interactions of leukocytes, also called white blood cells (WBCs), which are immune cells, with other leukocytes or with body cells. MHC ...


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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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What you are looking for sounds like the mechanism for a fold-change detector. I would recommend looking at these two papers: The incoherent feedforward loop can provide fold-change detection in gene regulation As an example of this working in a real system, I recommend looking at the NFkB pathway, as recently detailed by Suzanne Gaudet: Fold Change of ...


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In fact the line that you quote doesn't mean that the solution is formulated to be identical to the cytosol. All that it means is that the solution should be buffered to physiological pH (typically slightly alkaline); should contain a relatively high concentration of sodium ions and a low concentration of potassium ions; and should be isotonic (i.e have the ...


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Short-wave UV light (UVB and UVC) causes transition mutations at dipyrmidine sequences (ref.). In the work presented on KNSTRN quoted by the OP the authors report that 19 from a panel of 100 squamous cell carcinomas (SCC) contained a mutation in KNSTRN (and furthermore three of these contained no other mutation across the six genes that were analysed (Fig. ...


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This is actually a bad idea for severeal reasons: First it is not a good idea to tamper with genes, especially not with ones which are involved in the regulation of mitosis and the correct segregation of sister chromatids. Remember that a one amino acid exchange because of a C to T transition causes the problems with SCC? Into what do you want to change the ...


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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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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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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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I just took a quick look. These classes of enzymes are important to a family of lipid based molecules which perform intra and intercellular signalling with a lot of medical importance. Epoxygenases can create epoxides of arachidonic acid, which can modulate cell proliferation. Arachidonic acid is a well known second messenger in many tissues in the ...


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Maybe I'm missing something here (and it's not my area of expertise) but... the GHK formula includes the parameter Vm which is the transmembrane potential. This parameter is determined by the intracellular and extracellular concentrations of all ions. A high external concentration of Na+ will therefore influence the net movement of K+. One of the ...


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Most importantly, the whole Goldman-Hodgkin-Katz model is, well, a model. It is a way we would like to find and explain phenomena, given pen and paper. Often, scientists build models in order to explain data in hand, but even then, they will have to add something from their imagination. For example, early astronomers saw planets moving differently from ...


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Bianconi et al. 2013 give an estimated lower bound of 3.72 × 10^13 (which, by the way, is approximately the geometric mean of 10^13 and 10^14). However, from the table in their Supplemental Information (where estimates for about fifty different types of cells are added up), it is clear that the vast majority of these are the erythrocytes, also known as red ...


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This is a classic Fermi estimation problem. The usual approach is to estimate the volume of a body, estimate the volume of a cell, and divide one by the other, remembering of course to have both volumes in the same units. My quick attempt gave 1013 to the nearest order of magnitude.


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Find, or calculate, a value for the volume of the sperm head. Find a value for the size of the human genome (haploid or diploid?) Convert the genome size, which will probably in Giga basepairs, into mass (I suggest picograms). Divide mass by volume to get a density, pg μm-3 Refinement - does the sperm nucleus take up all of the head volume? Do you ...



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