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

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1answer
91 views

What type of flask should I use to culture NTERA2 embryonic cancer stem cells?

I'm just starting my MSc research and I am in the process of making a list of equipments/consumables to order. Is there a specific flask in which I can culture NTERA2 (NTERA2/D1) cell line?
6
votes
1answer
84 views

Why do most organisms have negative supercoiled DNA?

It has been observed that in nature most organisms have negative supercoiled DNA and that few organisms have positive supercoiled DNA. Some of the organisms that have the positive supercoiled DNA live ...
1
vote
1answer
21 views

How to correlate the pattern by which CAP activator from E.coli binds to DNA and its mechanism of action?

The catabolite activator protein (CAP) activates the expression of more than 100 genes involved in secondary sugar metabolism in E.coli. Apparently, it always binds in sites that are away from -10 and ...
5
votes
1answer
200 views

Why is E.coli used as a model?

Is there a reason for the choice of E.coli as a model for many bacterial systems? Other bacteria such as B.subtilis are also used, but why is E. coli preferred?
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3answers
4k views

What are the advantages and disadvantages of using beta-galactosidase compared to luciferase as a reporter gene?

In the University labs, we have used Beta-galactosidase as a reporter gene to quantify the expression initiated by the stress-response promoter in yeast. This was done by exposing one of the two ...
5
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2answers
144 views

What is the IC50 exactly?

I am reading the paper "Activity of the bcr-abl kinase inhibitor PD180970" but I don't understand how IC50 works on table 1. Can you tell with simple words and give me an easy example?
0
votes
1answer
58 views

What are microRNA, siRNA and antisense RNA?

From what I understand, microRNA binds to proteins which can cut certain mRNA strands do that this protein is not synthesised. This seems like gene silencing to me, however I have also come across the ...
4
votes
2answers
168 views

What's a protein pulldown assay?

I'm reading a paper and the authors mention a "protein pulldown" assay. I've never done this before, and googling doesn't bring up much. Could I get a rundown of the basic theory behind it? Also ...
1
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1answer
21 views

What are the roles of cadherins in epithelial mesenchymal transitions? [closed]

I know that cadherins control the expression of cancer cells involved in the epithelial-mesenchymal transitions, but I was wondering exactly how the process worked.
6
votes
1answer
62 views

Why do some bacteria have most genes on the leading strand of the genome?

Genes in the (+) strand are black and genes in the (-)strand are red. The gene distribution in E. coli genome is somewhat expected: transcribed regions would tend to alternate with non transcribed ...
6
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4answers
63 views

Enzymatic error rate

I am aware that each enzyme generate a certain amount of misproducts. This is well documented, for example, for the DNA polymerase. I am interested in enzyme involved in biochemical processes, so for ...
5
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2answers
85 views

The meaning of RNA-seq data

many papers I read mentioned "RNA-seq data". While searching for the meaning of this word, I could not find any layman's definition. As far as I understand, RNA-seq data is the complete RNA ...
4
votes
2answers
114 views

How does optogenetics work?

I am aware of the post here 'Optogenetics - How do microbial opsins work?' however it is a bit too technical for me. I am struggling to understand how the neurons can be genetically engineered to ...
2
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0answers
31 views

What is NK-cell compartments?

with respect to the paper: Adaptive reconfiguration of the human NK-cell compartment in response to cytomegalovirus: A different perspective of the host-pathogen interaction What is meant by ...
3
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0answers
38k views

Does CPH4 exists? [closed]

What is the purpose of CPH-4? Is it well represented in the movie Lucy?
4
votes
1answer
61 views

How can E. coli proliferate so rapidly?

The E. coli has a genome with approximately 5×106 bp. The main DNA polymerase involved in its chromosome duplication (DNA pol III , the one with highest processivity) can polymerize ~103 nucleotides ...
2
votes
1answer
23 views

What are host cellular factors?

With respect to this paper: Global Analysis of Host-Pathogen Interactions that Regulate Early-Stage HIV-1 Replication What does the term "host cellular factors" mean??
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2answers
52 views

Why mutations in genes involved in general processes like DNA repair increase the risk of developing specific types of cancer?

For example, mutation in MHS2, which encodes a protein involved in the repair of mismatches that occur during DNA replication, dramatically increases the risk of developing colon cancer. (There are ...
8
votes
2answers
270 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)? ...
0
votes
1answer
25 views

What sort of assay could be used to identify mutants with mutator phenotype? [closed]

By mutator phenotype, I mean being more prone to mutations, for example due to mutations in genes involved in DNA repair. I was thinking about exposing the cells to agents that damage DNA (uv light, ...
4
votes
1answer
280 views

What is our skin made up of?

Again, it is a basic question. What is our skin made up of? is it made up of many cells arranged in a systematic way or is it just like any layer say of a book?? what is the difference? where is the ...
5
votes
1answer
46 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 ...
2
votes
1answer
24 views

Electroporation of one-cell embryo?

Would electroporation be successful on a one/two-celled mouse embryo? If it would, what buffer could be used and what percentage of cells would be viable? Thank you.
4
votes
1answer
248 views

Why AZT is selective towards HIV and doesn't impair human DNA replication?

I've found this article, which is a very old one (from the time when nucleoside analogs where researched as a possible way to prevent replication of virus genetic material, before the HIV epidemics). ...
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vote
4answers
104 views

Why are there both stop and start codons?

Based on my understanding from wikipedia, there is the (RNA) start codon AUG and the stop codons UAA, UGA, UAG. AUG can also encode Methionine, I'm assuming if it appears in the middle of a mRNA ...
1
vote
1answer
590 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 ...
5
votes
1answer
123 views

Why does high pH result in the denaturation of DNA?

In the Southern blot method, for example, a solution of NaOH is used to denature the DNA in the sample. I find this counterintuitive since I expected that $\text{Na}^+$ cations would neutralize the ...
1
vote
1answer
43 views

What are pseudoknots?

I'm trying to get my head around what a pseudoknot is and how I can identify them given some RNA string. For example, suppose I have a string s = CGUUGUGUACACGAUAGUACAU. Suppose the two longest ...
0
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1answer
47 views

Examples of how the presence or absence 2'-hydroxyl groups influence physicochemical properties of DNA and RNA

I know, for instance, that RNA is much more succetible to alkaline hydrolysis than DNA and this difference is determined by the presence of 2'-hydroxyl group in ribose. I have also heard that "DNA is ...
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0answers
10 views

Why is carbonylation added as a fixed modification in mass spectrometry peptide analysis?

When using mass spectrometry analysis software we use carbonylation as a fixed modification. What is the significance of this modification and why doesn't it change?
2
votes
2answers
248 views

Why people fear GMOs? Can't we map a plant composition?

My main question is can we map what a fruit is made of? For instance apples are made of 0.0002% of protein X, 0.00001 of protein Y, 0.001% of amino acid Z... etc... If we can, then my next question ...
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0answers
14 views

Does the use of a Thiazide diuretic affect the ability of a hair follicle to absorb substances?

Thiazide diuretics are on the World Anti Doping Agency's, as well as the International Olympic Committee, list of banned substances due to it ability to mask illegal substances in urine. The rapid ...
3
votes
1answer
27 views

Authority on Microbiological Definitions

Is there an authority on definitions for molecular microbiology concepts, like an IUPAC book for chemical definitions? The particular definition I am debating is chromatin. Some say it encompasses ...
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0answers
36 views

If you are God, how would you create an efficient priming reaction? [closed]

Imagine that you are “natural selection” (or God if you prefer) and you can reconstitute replication changing the concentrations or the properties (higher/lower activity; reactivity; etc.) of the ...
3
votes
1answer
70 views

How is the type of genetic manipulation determined in CRISPR-Cas9?

I've been reading up a bit on the CRISPR-Cas9 system for gene manipulation. From what I read, it introduces double-strand breaks at specific points determined by the choice of sgRNA. But how do you ...
3
votes
2answers
174 views

In cancer, why do cells duplicate themselves?

In regards to cancer why do cells replicate themselves? If it's a mutation, what kind of mutation would this be classified as?
0
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2answers
51 views

mRNA Transcription from Nuclear DNA

How does a cell "know" the coding strand vs. the non-coding strand of DNA during transcription of mRNA?
4
votes
2answers
46 views

what does Pro→Glu substitution mean?

Considering the paper: A single amino acid in E-cadherin responsible for host specificity towards the human pathogen Listeria monocytogenes in the abstract portion, what does Pro→Glu mean? Does it ...
3
votes
3answers
74 views

Western Blot: Fischer ECL substrate 2:1 instead of 1:1?

i recently developed a b-actin-ab-incubated PVDF-WB-Membrane with the Thermo Scientific Pierce ECL Kit. According to the manufacterers orders i mixed Reagent 1 and Reagent 2 1:1. But unfortunately i ...
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0answers
39 views

Zinc and brewer's yeast

I'm hoping for some information relating to yeast nutrition (specifically Saccharomyces cerevisea) in beer fermentation. Zinc is well-known to be necessary for yeast cultures to perform successful ...
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0answers
55 views

How does estrogen influence collagen synthesis?

Through what mechanisms does estrogen interact with collagen synthesis? Especially in the context of elevated estrogen levels and genesis of purpura simplex .
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2answers
123 views

Growing E. coli at room temperature?

If I were to do a blue/white selection of transformed E. coli on LB agar ampicillin plates at room temperature (23⁰C) for about 2 days and 18 hours, will I run into the issue of satellite colonies or ...
3
votes
1answer
106 views

What do “e” “-” “C” and “E” mean in this output?

I have given an input of this protein sequence: MEPVDPRLEPWKHPGSQPKTACTTCYCKKCCFHCQVCFTTKALGISYGRKKRRQRRRPPQGSQTHQVSLSKQPTSQPRGDPTGPKE from this website along ...
2
votes
1answer
35 views

Why is the resting potential of a neuron so close to the equilibrium potential of K⁺?

I know this has something to do with the K+ leak channel. I just don't understand how. I know that 3 Na+ are pumped out for every 2 K+ pumped in. This makes the cell interior net negative. I know ...
8
votes
2answers
554 views

What is it about the housekeeping genes that makes them almost immune to gene regulation?

When it comes to eukaryotes, including ourselves, we have all different kinds of specialized cells and tissues that are so different, yet originally all came from the same single cell. And apparently ...
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0answers
18 views

How to engineer chromosomal duplications?

Specific genetic engineering of chromosomal aberrations like deletions, inversions and translocations are doable by using the CRISPR/Cas system or the other programmable nuclease systems. Insertions ...
6
votes
1answer
74 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 ...
0
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0answers
23 views

Cannot conjugate Biotin-labeled DNA to Streptavidin-labeled solid surface

I have been trying to immobilize DNA by the bioconjugation of biotin and streptavidin, but I cannot get this work. I added EDC and streptavidin to COOH ...
2
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0answers
13 views

Gene expression for mouse feeder cells (inactivated MEFs)

I'm looking for a paper with gene expression data for mouse feeder cells, inactivated by gamma radiation or mitomycin C. Ideally I'd like RNA-seq data but I'll use microarray data if that's all there ...
2
votes
1answer
50 views

How do C. elegans manage 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?