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

learn more… | top users | synonyms

1
vote
0answers
17 views

de novo gene synthesis vs cDNA library creation from plant RNA: Pros & Cons

What are the relative pros & cons of the following two approaches when one wants to insert a known, sequenced plant gene into a target host organism: de novo gene synthesis vs plant matter ...
13
votes
1answer
16k views

Why is ATP the preferred choice for energy carriers?

Why is ATP the most prevalent form of chemical energy storage and utilization in most cells?
1
vote
1answer
101 views

How the chaotropic agents help in purification of DNA molecule?

Those plants which are rich in secondary metabolites and polysaccharides DNA isolation can be done using certain chaotropic agents? can any one explain how it works?
3
votes
1answer
72 views

Why does Taq polymerase add 3' adenine overhangs?

Is there a mechanism for the preference of Taq polymerase to add a non-templated 3' adenine (overhang) instead of other bases?
1
vote
1answer
52 views

What are the problems in using an ssDNA or an mRNA for expression instead of using a plasmid?

Let's say you want to do a gene cloning experiment. You have an empty expression vector (mRNA or DNA) and are looking to clone some gene X into it. Why is it you can only buy X already inside a vector ...
0
votes
1answer
27 views

Synthesis of an additional DNA in Pachytene and Zygotene [closed]

I've read, that in Pachytene and Zygotene additional DNA material is synthesized, about 0,3, 0,1% respectively. Why is it so?
1
vote
1answer
55 views

How RNA primer on leading strand is removed during DNA replication and how the gap is filled? [closed]

Please can you explain me how the gap created by the removal of primer on 5'-3' leading strand is filled.
8
votes
3answers
368 views

How does the body switch between aerobic and anaerobic respiration?

Lets take the case of a person doing heavy exercise. Aerobic respiration is taking place, but oxygen is about to be finished up. Glycolysis occurs, Krebs cycle finishes. Now NADH and FADH enter ...
3
votes
0answers
36 views

Are all genes transcribed in differentiated cells?

My textbook tells me that it’s specific transcription factors that allow for a different set of genes to be expressed in different cells (differential gene expression). My book gives the example of ...
1
vote
1answer
37 views

does life make or break?

Ok, this question seems like it may be impossible to answer, but would be interesting to see if anyone has an idea. Throughout the course of a human life, do we make more molecular bonds than we ...
7
votes
1answer
114 views

The mechanism of mechanoreception?

I am interested in knowing the molecular mechanism behind mechanoreception/mechanotransduction (i.e. mechanism behind receptor potential generation on mechanical stimulation). I know that most ...
1
vote
1answer
112 views

An experiment to test if a bacterial resistance gene is on the plasmid or chromosome?

So I have an E.coli strain phenotypicall resistant to the antibiotics ampicillin and rifampicin. How do I test if the AmpR gene is carried on a plasmid and not on the chromosome? In summary, I ...
1
vote
1answer
19 views

Molecules, Targets and Isoforms

I have a question. Given a molecule A and two isoforms of a gene X, Y, and the knowledge that A targets X. Can I infere from this anything about whether A targets Y? As a motivation think about ...
0
votes
0answers
10 views

Are there in biololy specific QM-phenomena which are necessary for their processes?

Of course QM should be every where, because that is how nature is. But for example if you take the fusionprocess of our sun it appears that the sun wouldn't give any heat and light without making use ...
4
votes
0answers
34 views

Artificial reduction of NADP into NADPH by means of an electrical current

I've recently been attempting to artificially drive the formation of NADPH via the NADP reduction mechanism utilized by Ferredoxin-NADP Reductase in the Light-Dependent Reactions of Photosynthesis in ...
2
votes
1answer
50 views

Why does protein kinase C activated by different means have different effects?

I could be way off base but I think I remember learning that Protein Kinase C has some effects when activated by one pathway and other effects when activated by another. How does this happen? Is it ...
3
votes
1answer
75 views

Is a bone marrow transplant limited by sex?

Can a female patient get transplanted with bone marrow of a male donor and vice versa?
10
votes
1answer
348 views

Restriction enzymes, how are the recognition sequences determined?

How were the recognition sequences (e.g. GAATTC of EcoRI, GGATCC of BamHI) characterised? Text books only list the recognition ...
8
votes
2answers
74 views

Is there a metabolic pathway 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 toxicity?...
1
vote
1answer
93 views

What is two-start or zigzag model of 30 nm chromatin fibre?

I read some webpages describing the two-start model but could not get it. I'll be obliged if someone helped me understand the topic. The websites I have been through are: 1.http://www.nature.com/nrm/...
4
votes
2answers
112 views

Is it possible to create a restriction map using python? [closed]

I have some fragments of DNA from single and double digests using three different restriction enzymes. I'm trying to construct a restriction map of a linear fragment of DNA. The map needs indicate the ...
3
votes
0answers
51 views

How can a mutator gene can cause a mutation when it is shut off? [closed]

defination of "Mutator" - a gene that increases the rate of mutation of one or more other genes. However, in the book "Molecular Biology of the Cell" (bruce alberts) it states that when a mutator is ...
1
vote
0answers
213 views

Construct a restriction map of a linear fragment of DNA using the following data?

I've attempted to do the single digests, and the double digests, but cannot complete the map.... I've attached what I've done so far DNA Sizes of Fragments (bp) uncut DNA 900 DNA cut with EcoRI ...
1
vote
0answers
19 views

Enzyme immobilization: Factors that help or hurt success

Are there any factors to consider that can help / hurt the chance to get a successful immobilized enzyme catalyst? i.e. The relative attractiveness of a live host synthesis vs an immobilized enzyme. ...
1
vote
1answer
45 views

Lookup for transporter locations in humans

I am interested in several transporters and cotransporters (eg SLC12A1/2 and many others), more precicely, in (human) organism that are made of cells containing those transporters. So does anyone know ...
8
votes
2answers
259 views

How does LCR compare to Assembly PCR

The question pretty much explains itself. How do the two methods compare? I've always used Assembly PCR but the method is prone to mistakes and I'm curious how it compares to Ligase Chain Reaction (...
2
votes
2answers
42 views

What separates gene loci?

Introns are sections of noncoding DNA that separate exons within a gene locus. However, between different gene loci, I also would assume there to be noncoding regions of DNA. What are these regions ...
2
votes
3answers
202 views

Why don't housekeeping genes have TATA Box regions in their promoter sequences?

Housekeeping genes are genes that are continuously transcribed. Like all other genes they have promoter sequences, but they don't have TATA box sequences that are used to specify from where ...
1
vote
0answers
22 views

Computer Models of E Coli / Saccharomyces cerevisiae metabolite pathways

Are there mathematical models one can use to predict the expression levels of a foreign gene inserted into a well studied host organism like E Coli or S cerevisiae? I'm not, obviously, looking for ...
1
vote
0answers
18 views

codon optimization / enzyme active site improvement

Does one necessarily have to use de novo synthesis of DNA when attempting protein expression improvement by codon optimization? Or are there other ways? e.g. Say the gene coding for the enzyme needed ...
0
votes
2answers
129 views

Definition of Phenotype

I'm not a biologist but, I'm trying to enter molecular biology from a perspective. I have noticed that concept of genotype is quite well defined while ...
2
votes
1answer
53 views

What is the P in LogP? [closed]

How does this value actually get calculated? Logarithms are usually written as log(base 10) of x So what is the 'P' equivalent of 'base 10'? I know it stands for octanol/water, but what does that ...
2
votes
2answers
38 views

Was there originally a non-ribosomal way of synthesizing proteins?

Proteins are synthesized on ribosomes from mRNA copies of regions of the DNA. But ribosomes themselves are made up of proteins (and RNA). So how could the first ribosomes have arisen? Was there ...
1
vote
0answers
21 views
3
votes
1answer
68 views

How do the major and minor grooves in the DNA helix arise?

I understand that they arise due to the pairing of bases of two opposite stands and are sites through which important proteins needed for replication and transcription of DNA interact. But I don't get ...
1
vote
0answers
20 views

What is the site on an enzyme that binds either exitatory or inhibitory molecules? [closed]

A site on an enzyme where either exitatory or inhibitory molecules can bind is called a(n): A) electron transport site B) active site C) coenzyme D) metabolic pathway E) allosteric site If you ...
3
votes
1answer
26 views

How can dopamine modulate synaptic strength?

Does dopamine act on G protein coupled receptor, leading to more Ca2+ channels on the postsynaptic knob? Also, how is the specificity of the location (of the brain) that dopamine acts on controlled? ...
1
vote
1answer
41 views

How does cytochrome c oxidase inhibition cause cell death?

I realise the inhibition of cytochrome c oxidase prevents the release of H+ ions into the intermembrane space, and that the ion gradient is required for ATP synthase action. However, I'm not sure how ...
1
vote
1answer
35 views

BWA-MEM single strand or doublestrand alignment

In whole genome secondary analysis does BWA-MEM use a double stranded fasta reference or are reads aligned to only one, single stranded fasta reference?
3
votes
1answer
57 views

Does DNA polymerase I require a $3^\prime$ end?

DNA polymerase III adds nucleotides in the $5^\prime \rightarrow 3^\prime$ direction because it can only add nucleotides to the $3^\prime$ end of the previous nucleotide. This is why it requires a ...
1
vote
0answers
28 views

Hydrogen bonding and the blocking thereof in nucleic acids during nuclear processes

In transcription, RNA polymerase unwinds the DNA double helix and begins attaching RNA nucleotides to the template strand. In its wake, the DNA double helix closes back—this is only natural, seeing as ...
4
votes
1answer
54 views

Function of NaCl in yeast shuttle prep of plasmids

What is the role of NaCl in plasmid isolation from yeast cells using plasmid rescue solution? If the basic theory behind the method is alkaline lysis, then we is NaCl used and not NaOH?
1
vote
1answer
31 views

How to induce a steady increase in cyctoplasmic [Ca2+] in HEK293T cells? And is there any simple marker/method to confirm it?

We are trying to find out whether increase or decrease of cytoplasmic calcium concentration affects the interaction of two proteins, using co-IP in HEK293T cells as a readout. In different forums and ...
1
vote
1answer
43 views

Molecular/cellular biology textbook to consolidate what I know about molecular/cell biology

I'm a medical student (who is halfway through med school) looking for a textbook that will consolidate some of the biology I already know. While I've read a lot of books that go into great detail ...
1
vote
3answers
40 views

Statistically, why is the number of mutated genes in eggs treated with chemical mutagenesis one?

Excerpted from the Guide to Research Techniques in Neuroscience [1]: In chemical mutagenesis, a scientist applies a mutagenizing chemical, such as ethyl methane sulfonate (EMS) or N-ethyl-N-...
0
votes
1answer
43 views

What's the mixture of plasma and haemoglobin called [closed]

I know of oxyhaemoglobin but the mixture of plasma and haemoglobin in the blood gives what?
0
votes
1answer
52 views

What's the mixture of carbon and haemoglobin called [closed]

I know of oxyhaemogloblin , the mixture of oxygen and haemoglobin , but carbon and haemoglobin combination is what's confusing
1
vote
2answers
91 views

Getting PCR amplification at annealing higher than Tm!

I am amplifying a gene where in a gradient pcr i am getting amplification at an annealing temperature about 5 degrees (67) higher than Tm (62.5)? What is wrong here? Also, I am getting a very strong ...
1
vote
1answer
76 views

Primer Design with Primer-BLAST over specific site

I am trying to design primers using Primer-BLAST such that the forward primer spans a specific base pair site. I am looking at KRAS for which I believe the RefSeq ID is NG_007524.1 and the forward ...