The study of the molecular processes of the nucleus and cell function.

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Is wiping with RNAse Zap enough to destroy RNAse activity?

From the RNAseZap MSDS, it is an SDS at some unknown concentration, maybe with some NaOH? Some other links suggest there is some NaOH as well. The Ambion site states that RNAseZap destroys RNAse ...
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How can histidine be classified both as positively charged and hydrophobic?

I saw the chart in this post Histidine aromaticity. Since I'm not allowed to comment and post a question instead of an answer, I have to ask my question in a separate thread. How can histidine be ...
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27 views

C. elegans and nutrition

If there is ample amount of food, do C. elegans worms know when to stop eating or do they store extra energy? Could they put this extra energy to use by moving faster or putting more eggs?
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61 views

How exactly can dsRNA be introduced to a cell?

Is it just by viruses or are there other means by which it gets into cells, such as plasmid uptake?
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105 views

How to find miRNA binding sites on a specific gene?

I am trying to find miRNAs that bind to the 3'UTR of a specific gene. What is the best way of doing that (that is, with a good scoring analysis that is most commonly used by researchers in this area)? ...
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670 views

Why does replication require primers while transcription does not?

In transcription, there is no need for any primer. I guess the basic mechanism of DNA polymerase & RNA polymerase is the same. So why does replication have the need for a primer?
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63 views

Redundancy of the genetic code

One particular codon codes only for one amino acid, but an amino acid can be coded for by several different codons. Now according to the genetic code, the codon UUU ...
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78 views

Can a human cell live indefinetely in a controlled environment?

How long can a human cell live in a controlled environment, given all necessary nutrients, temperatures, mechanisms for waste removal, and other requirements are provided for? Put differently: Can a ...
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337 views

How to convert nanogram to picomole? [closed]

I have lets say 10ng/uL of RNA. How can I convert it to picomole? I need it to calculate how much magnetic beads I need. This is the product: ...
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58 views

How does high-fidelity of DNA replication depend on the formation of hydrogen bonds?

Replication has an error rate of less than 1 in 100 million. DNA polymerase forms H-bond with the H-bond acceptor atoms in the minor groove. <-- enhance fidelity here? Binding of the triphosphate ...
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84 views

Alternatives to trypsin for cell detachment?

I have ran out of trypsin and need to passage my cells (immortalized chondrocytes, C28/I2) today or tomorrow. I have been out of town and forgot to order more trypsin. I was wondering if there are ...
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54 views

How does non-homologous end joining (NHEJ) work?

I was reading about non-homologous end joining (NHEJ) in my molecular biology of the gene textbook but the explanation provided in the text was rather vague to me, and I was not able to understand it ...
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66 views

peptide MHC microarray

"The recent technology is peptide–MHC microarray or artificial antigen-presenting chip. In this technique, recombinant peptide–MHC complexes and co-stimulatory molecules are immobilized on a ...
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465 views

Has anyone tried Gibson Assembly Optimizations?

Has anyone tried the chew back-anneal in vitro DNA assembly method (known as Gibson Assembly) for difficult sequences, like GC-rich sequences? How big constructs could you efficiently assemble? Did ...
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1answer
27 views

Does adding antibiotic after 5-10 mins of innoculation affect the protein yield or growth?

I've asked a lab colleague the same question. She said, it would loosen the bacterial cells in the LB medium and plasmids would come out. Is that true? and why?
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1answer
125 views

Active & passive transport question

If an element, ion or molecule is found in a cell is it possible to tell which method of transport was used? for example if a hydrogen or sodium ion was found in the cell could you tell if it got ...
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1answer
125 views

What is the extent of the effect of Tris on E. coli?

I was a fool and dissolved my antibiotic (Kanamycin) into Tris Buffer rather than H₂O. The Kanamycin still seems to be active but a fellow labmate mentioned that Tris messes around with the membrane ...
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188 views

Why proteinase K doesn't degrade itself?

Can anyone tell me why proteinase K doesn't degrade itself? If possible please provide me the source.
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1answer
185 views

How many RNA-binding proteins can simultaneously bind on a single mRNA?

Typically, how many RNA-binding proteins can simultaneously bind to a single mRNA? Or said differently, how many "binding sites" does an mRNA have? What order of magnitude? I am interested in RNA ...
4
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1answer
44 views

protein-binding sRNAs

I am actually a computational biologist, pardon me if my question description is a bit off-note, my curiosity is driving me on A bit of background and context: In bacteria, a regulatory protein ...
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131 views

When did CRISPR/Cas9 evolve and what is the likelihood that a superior system for live cell genome editing has already evolved on earth since then?

I've read that CRISPR/Cas9 is currently being implemented and tested for its ability to edit genomes in live cells, and that it is supplanting other genome editing tools in labs, such as TALENs and ...
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18 views

Sequence based method for prediction of continuous B cell epitope

What is Sequence based method for prediction of continuous B cell epitope? What is the algorithm/procedure of this method? Can someone please explain this to me in simple language?
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314 views

How do antioxidants affect human metabolism?

I'd like to know how antioxidants affect human metabolism and which ones are essential for metabolic processes.
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28 views

Receptors for red and far-red light in plants: Shade avoidance

Franklin (2009) describes how plants use the ratio of the red wavelength (660-670nm) over the far-red wavelength (725-735nm) (R:FR) in order to avoid shading. My question is: which receptor is ...
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1answer
46 views

A monkey typing Shakspeare? [closed]

I think that the ultimate and most important question of biology and science is the origin of life. Was it the result of pure probability? Or was it the result of the law of physics? In other words, ...
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recombinant peptide MHC complex

What is recombinant peptide-MHC complex??? Recombinant DNA means "to bring together genetic material from multiple sources, creating sequences that would not otherwise be found in biological ...
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1answer
35 views

Determining and Differentiating specific ATPases

In respects to this certain ATPase transporter. What do i look for in respects to determining what specific kind it is out of: F-ATPases V-ATPases A-ATPases P-ATPases E-ATPases Im assuming that ...
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Transmembrane Protein Problem

Problem A transmembrane protein has 1000 aa. The 5th aa is found on the external side of the cell membrane. It interacts with the aqueous environment outside the cell. Amino acid 90 is inside the ...
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1answer
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How does a TOPflash/FOPflash assay work to detect beta-catenin protein expression?

I am reading an article (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3596711/) wherein a TOPflash/FOPflash assay is used to detect beta-catenin protein levels in a COS-7 cell line. I can't find a good ...
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1answer
23 views

epitope prediction/ mapping

B-CELL EPITOPE PREDICTION Regarding this article: "Such a molecule can be synthesized or, in case of a protein, its gene can be cloned into an expression vector."----- is a particular line in ...
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25 views

How does Temperature influences the rate of protein turnover? [duplicate]

Question How (quantitatively speaking) does temperature influences rate of turnover of transcription factors? Which protein? As I am not looking for any accurate number I am talking about an ...
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1answer
25 views

aspartame in relation to generating methanol

So I posted another question with respects to methanol and aspartame in metabolism with respects to toxicity. So another question I have is "Why is aspartame used as a dietary component to generate ...
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Metabolism that generates methanol

I've been looking for help topics about methanol in metabolism. Specifically I wish to know What is a common dietary component that generates methanol following metabolism and comment on its ...
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0answers
23 views

What is Colloidal biology and does it have any scientific background?

There is the following bulletin published for the History of Chemistry Vol. 32: 105-118 in 2007: “MOLECULAR” VERSUS “COLLOIDAL”: CONTROVERSIES IN BIOLOGY AND BIOCHEMISTRY, 1900–1940* written by PhD ...
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39 views

What keeps resting potential of neurons constant at -70mV?

I know the sodium-potassium pump pumps out 3 Na+ ions and pumps in 2 K+ ions per reaction so the negative charge in the axon increases. However, once the voltage (difference of charge inside and ...
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transfection of expression library made from cDNA into cells expressing the desired MHC haplotypes [on hold]

http://www.sciencedirect.com/science/article/pii/S0167569997800205 If anybody has access to this paper, can you please explain me the process to find TAA based on transfection of expression library ...
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62 views

Why aren't introns found on the ends of pre-RNA?

We recently learned in genetics class that exons always cap the ends of nascent RNA. I have been trying to figure out the reason why introns can't instead be found on the ends instead of exons. The ...
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2answers
62 views

Manufacturing of Bio Molecules [closed]

Can we Manufacture bio molecules say e.g. the simplest Sugar, C12,H22,O11 the way we do with any other mechanical component. So, we know all about the Structure and arrangement of Atoms in Sugar - so ...
2
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1answer
57 views

Difference between sequential and conformational epitope

Is the difference only in its structure? Like conformational epitope has 3D structure while sequential has a linear structure?(I have not studied biology since last 8 years and now I am going through ...
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MHC restricted peptide

What is an MHC restricted peptide? "MHC-restricted antigen recognition, or MHC restriction, refers to the fact that a given T cell will recognize a peptide antigen only when it is bound to a host ...
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1answer
57 views

Influence of temperature on protein binding and decay rates

For computer modeling purposes, I am looking for some referenced quantitative measurements of the effect(s) of temperature on the dynamic of biochemical reactions. Question In particular, my ...
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2answers
45 views

Simulating Drug Entry in Protein and binding?

Is there any simulation protocol or paper which can simulate the dynamics of drug entry and interaction with the target protein?
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1answer
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What are the molecular mechanisms behind tachyphylaxis (downregulation of receptors in response to an agonist?)

Anyone know of a good source which explains this? Or is this still an open question? This wikipedia article describes some molecular biology behind morphine tolerance, but it sounds like its newer ...
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1answer
49 views

How is the rate of transcription influenced by temperature?

How is the rate of transcription influenced by temperature? More precisely, I am looking for an article who quantitatively measured the rate of transcription of an "average gene" and show how this ...
4
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1answer
63 views

Influence of temperature on transcription, protein binding and decay rates

I am the kind of biologist who doesn't know much about molecular genetics and about the dynamic of biochemical reactions. Question My question concerns the influence of temperature on the dynamic of ...
2
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1answer
27 views

Transcription rate expressed in microarray per hour

This article gives measurement of transcription rate and the unit they're using is microarray per hour. For example, at 27°C the average expression of their genes is 236.1 microarray per hour (page ...
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1answer
36 views

SEREX serological analysis of cDNA expression library

What is Serological Analysis of cDNA expression library? I went through this article:http://cancerimmunity.org/serex/introduction/ but could not really make out. Can someone please explain this to me ...
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1answer
191 views

What is the difference between second and third generation sequencing

I am writing the section about history of DNA sequencing in the introduction chapter and after reading quite a few research papers, I am still confused about them. Here I compile some questions to ...
5
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1answer
186 views

Importance of knowing GC Content of an organism

I was looking at the GC content percentages of few organisms. I also know calculating the GC content percentage. But, what I want to know is, what information would we get., let us suppose if human ...
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1answer
143 views

Complementarity Determining Regions (CDR)

Complementarity determining regions (CDRs) are part of the variable chains in immunoglobulins (antibodies) and T cell receptors, generated by B-cells and T-cells respectively, where these molecules ...