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5

Mitochondria produce a large quantity of reactive oxygen species (ROS) that damage the mitochondrial genetic material. These cell organelles do not have a DNA repair mechanism, so the fusion and fission of mitochondria work together to maintain as many viable/healthy mitochondria as possible. When two mitochondria fuse, their genetic material can recombine ...


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In this article it is described that starved macrophages 'consume' heat inactivated bacteria through phagocytosis with enhanced ability. Starving can also induce (macro)autophagy and the pathways are connected with phagocytosis,in the macrophages under investigation it was shown that autophagy did not play role in the enhanced ability of phagocytosis. The ...


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Cytoskeletal nucleation refers to the de novo formation of cytoskeleton filaments. If microtubules are nucleating, that means microtubules are being polymerized from lit. "From the beginning" by α/ß-tubulin dimers. So literally, and we see in the image below, Arp2/3 complexes act as progenitor sites so to say for new actin filaments by the "nucleation" of ...


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No, this does not happen, as the DNA polymerases used for PCR are DNA dependent. This means that they only synthesize DNA when it is bound to DNA. Even if your primers bind to the RNA, the polymerase will not starting new strands here. To use RNA as a template for PCR you first need to reverse transcribe it.


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First of all MHC stands for major histocompatibility complex. There are two types of MHC. MHC type one is present on all of our cells with a nucleus. The purpose of these protein complexes is called antigen presentation. T-cells cannot recognize free antigens on their own, it has to be presented to them in the proper way. This is what these proteins do. In ...


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Positive feedbacks can be one alternative. Positive feedbacks exhibit bistability and can therefore adopt one of the two stable states depending on the initial condition. A famous example of a positive feedback switch would be that between cI and Cro in λ-phage, which repress each other. Positive feedbacks also display hysteresis: if the state of the system ...


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I've found an old paper using radioactively labeled bacteria to track their fate in macrophages. According to the data, both $^{14}$C and $^{32}$P are reutilized in the host cell. COHN ZA. (1963). The fate of bacteria within phagocytic cells. I. The degradation of isotopically labeled bacteria by polymorphonuclear leucocytes and macrophages. J Exp Med. Jan ...


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The inclusion of formaldehyde in the gel and buffer is to keep the RNA denatured (ie after heating the sample to melt the double-stranded stem-loops, just prior to loading the gel), in the hope that the RNA will migrate through the gel with an Rf proportional to its molecular weight (approximated here by its length). Therefore the correct size markers would ...


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According to Kroeker WD, Kowalski W, Laskowski M. 1976. Mung Bean Nuclease I. Terminally Directed Hydrolysis of Native DNA. Biochemistry 15(20):4463-4467 It was concluded that the products of the terminally directed hydrolysis of native DNA possess 5’-phosphoryl groups because: (1) greater than 99% of acid-soluble activity applied to the column was ...


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Transcription interference can also be a good mechanism to provide such switches. Transcription interference occurs between genes in close adjacency to each other. This is basically, as the term suggest, that the neighbouring genes can interfere with each others transcription (by overlapping promoters blocking transcription initiation, collision of ...


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I think the opposite list---what features of life might be reasonably expected to be the same elsewhere---would be much shorter. Nearly every feature of life on earth as I can think of it is arbitrary in the particular molecules. DNA. Why only 4 bases? Why the bases that we have (ACTG)? Researchers are able to create organisms with expanded DNA alphabets ...


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Oligos from well-known companies are pretty good to my knowledge. Problems begin after 100-300bp oligos/dsDNA fragments. What I suggest is PCRing your vector like that: Primer F: ---------------------__________ vector: ======|v site for 36 bp insert v|==========... Upstream Downstream ______----------------- ...


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The question is following: did you incubate cells on ice before spinning? Protocol, for example this one for $DH5\alpha$, calls for just 10 minute incubation after heat shock: Heat shock at exactly 42°C for exactly 30 seconds. Do not mix. Place on ice for 5 minutes. Do not mix. Pipette 950 µl of room temperature SOC into the mixture. Did you ...


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This is hard to answer since we don't know the exact conditions you chose, as these are rotation speed (or better g), how long you spun them down and also if you used a cooled centrifuge or not. It's also important how gentle you resuspended the pellet. However, I would plate these cells, no matter what happened since you are at the last step of the ...


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No. DNA, and RNA have a polarity in the orientation of their sugar-phosphate backbones, based on the numbering of the carbon atoms in the sugar rings. So, for example, we say that the sequence of this RNA is being read from the 5' to the 3' end, which indicates that the first nucleotide is exposing the hydroxyl at the 5’ carbon on its sugar ring. At the ...


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In my experience, transduction efficiencies skyrocketed when I applied a spin-infection procedure. A 30 min low speed centrifuge with the virus changed a lot. Here is the TRC protocol for this: http://www.broadinstitute.org/rnai/public/dir/download?dirpath=protocols/production&filename=TRC%20viral%20infection%20200909.pdf


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Thermo Fisher has a protocol for the separation of host mammalian RNA from prokaryotic RNA, optimized for E. coli vs human, mouse or rat sequences. Capture oligonucleotides bind portions of the mammalian RNA and hybridize. These hybridized oligo/RNA are then removed from solution via "oligonucleotide-derivatized magnetic beads," after which the remaining RNA ...


1

The answer is in the slides you provided a link to. The key fact is that Craig & Andy did careful controls to show that it was the presence of dsRNA in both the sense control, and in the anti-sense experimental sample that was responsible for the RNAi-mediated knock-down. Actually, Ken Kemphues showed this earlier in a Nature paper (the control also ...


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While there is unlikely to be any activity when the enzyme is frozen, there are better methods to prevent star activity. 1: If you are running the reaction in a PCR machine, you can program the machine prior to the digest to heat up to 65 degrees for 10 minutes after the intended digestion timeframe to heat inactivate NotI. Since NotI is a heat-labile ...


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Deinococcus radiodurans did not "develop resistance to mutations". It is able to repair its chromosome when scatered in pieces by radiations or desiccation, while other bacteria would die in such conditions. So this is adaptive in extreme environments, such as deserts (where it has evolved) or canned corned beef (where it was discovered).


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If I understand correctly you are preparing your cloning vector by digesting it with two enzymes that are 31 bp apart. If you have a high background of recircularized vector see if there is a unique restriction enzyme site within that 31 bp. If there is, and if the fragment you are trying to insert also lacks that site, then a simple approach would be to ...



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