Questions tagged [molecular-genetics]

The scientific study of the structure and function of genes at the molecular level, particularly chromosomes and DNA.

Filter by
Sorted by
Tagged with
2
votes
2answers
611 views

Alternatives to PCR

PCR uses cycles of heating and cooling to denature the strands, calling for special thermostable DNA polymerases. In a cell, during replication, Helicase unwinds the DNA without the requirement of ...
4
votes
2answers
899 views

How does Cro protein expressed by lambda phage kill its host?

I read that the DNA segment of lambda phage integrated in host DNA could switch between lysogenic state where cI represses the expression of Cro and lytic state where Cro expression takes over and ...
1
vote
1answer
255 views

tandem repeat sequence; causes of contraction and/or expansion question

Question: Which of the following events, occurring within a tandem repeat sequence, will cause an expansion or contraction of the array? A) Endoduplication B) homologous recombination C) ...
1
vote
0answers
831 views

mutations induced by transposons

Question: In contrast to chemically-induced mutations, mutations induced by transposons are more likely to ... be lethal de dominant be stable revert to wild types be a gain of function The answer ...
6
votes
0answers
176 views

Comparative cost of RNA-seq vs sequencing full length cDNAs

I am in the process of assembling and annotating the genome of a non-model organism, using almost exclusively short read (paired-end Illumina) data. Throughput is one obvious benefit of these data (...
3
votes
3answers
359 views

Abbreviations for molecules: What are CheW, CheA, CheY?

I've encountered the abbreviations such as "CheW" and "CheA" for certain organic molecules. For example: Proteins associating with the Tar complex include the autophosphorylating protein kinase ...
0
votes
2answers
209 views

how do I find the number of bp in chromosome 3 by knowing number of bp in chromosome 1?

If i have a number of bp in chromosome 1 for example(298,295,559 bp) can I use this number to find the number of bp in chromosome 3.
-2
votes
1answer
129 views

DNA Replication And Primer [duplicate]

Why does nature rely on RNA primer for the start of DNA Replication? Why not simply use DNA primer and make life simple !
0
votes
0answers
78 views

Why is dsDNA nuclease activity by CRISPR/Cas9 only shown indirectly?

In Jinek et al., the authors show nuclease activity of their CRISPR/Cas9 system using the so-called Surveyor assay method. This assay recognizes small mismatches in dsDNA which are introduced by error ...
0
votes
1answer
318 views

Layman definition of genetic polymorphism?

I am reading an article about Genetic Polymorphism and there are lines in the article about genetic polymophism that I don't quite understand like. In this area, there are six different chemotypes ...
2
votes
0answers
75 views

How does intron retention make the alternative transcript non-coding?

I faced with a non-coding transcript that specified as one the isoform of BIN1. It sounds that this isoform generated as a result of alternative splicing with a intron retained; am I right? However, ...
8
votes
5answers
9k views

What's the aim of genetically modifying of foods/organisms?

On news, articles etc. experts talking about Genetically Modified Foods and Organisms often mentions about their disadvantages like, their potential to harm human health allergies may become more ...
2
votes
2answers
6k views

Are eukaroytic promoters located in the 5' UTR region?

I was wondering if promoter sequences are located on 5'UTR region in eukaryotic organisms?
3
votes
2answers
902 views

Do transposons usually jump from one chromosome to another?

If it is usual occurrence, does it mean that my one gene can change its location from one chromosome to another?
0
votes
1answer
737 views

Catenation and decatenation by DNA Gyrase

Decatenation is done for the replication of DNA and why is Catenation done and is it related to Crossing over
3
votes
1answer
158 views

Genetics of epilepsy

Is epilepsy genetically inheritable? If yes, is it dominant?
3
votes
1answer
1k views

What is a holocentric chromosome?

I was doing this question that asked: "How many centromeres does a typical chromosome have?" I thought one and the answer was:"One, except for holocentric chromosomes." So then what are "...
6
votes
3answers
14k views

Why is mRNA needed in the Protein translation?

The original question was to predict the basic requirements for information storage. Then the discussion moved to why is it necessary to include mRNA in the protein translation process. Why can't ...
4
votes
1answer
4k views

How long is saliva viable?

Does anyone know if saliva can stay viable for about 5 days, before it gets suspended into a DNA genealogy vial for testing? Background: My brother wants to do a DNA genealogy test at a US testing ...
2
votes
1answer
25 views

How and why are cells irradiated in human-rodent hybrid cell biology?

When human-rodent hybrids are made the amount of human chromosome in the hybrid can be reduced by irradiation. Why and how exactly is this irradiation step performed?
1
vote
1answer
370 views

How do signal transduction pathways utilize transcription factors to express a specific gene?

I have an inquiry regarding the regulation of genes via extracellular signaling. To my knowledge, in autocrine, paracrine, and endocrine cellular communication, large protein ligands that cannot ...
3
votes
1answer
239 views

Explanation about cytogenetic notation

What is the correct meaning of cytogenetic notation "inv(4)(p13q22)" ? Inversions at chromosome 4, at the p arm 13 is inverted AND at q arm 22 is inverted OR Inversions at chromosome 4, the p13 ...
4
votes
2answers
8k views

How many copies of a gene?

I am studying mathematical models of transcription and translation and I am wondering: In a particular genome, how many copies of a gene coding for one particular protein should one expect? Are they ...
3
votes
1answer
350 views

Is sequencing error a function of the nucleotide being read?

Checking out on Google Scholar, I can see that for Illumina (just to consider one example) the sequencing error rate is of the order of 0.001-0.01 per nucleotide. Talking about sequencing error, let'...
1
vote
0answers
37 views

Is a Ribonuclease Inhibitor protein the only mechanism employed by the human cell to protect cellular RNA from degradation by endoribonuclease?

Are there any other methods of protection for cellular RNA from degradation by endonuclease (specifically the Pancreatic Ribonuclease RNase II (Eosinophil-derived neurotoxin) and RNase III (Eosinophil ...
1
vote
1answer
798 views

Gene and Protein isoform

What is the relationship between term "Gene isoform" and "Protein isoform"? Say a gene can make 3 isoforms, will it produce only (maximum) 3 isoform protein?
9
votes
3answers
2k views

Methods of nuclear transfection - nuclear transport

I am reading through the ENCODE papers, which is taking me well out of my comfort zone in terms of modern laboratory techniques. At the risk of asking a question which may well be thoroughly answered ...
-1
votes
2answers
5k views

Why does a gene have two alleles? [closed]

Why does a gene have two alleles? When there is a gene for producing the color pigment for a flower, why are there there two alleles, producing either same color or different color (homozygous and ...
0
votes
3answers
798 views

Sense and anti sense strand

Why the sense strand is only involved in transcription though the antisense strand just has the compliment strand of the sense strand?
2
votes
1answer
109 views

DNA dependent RNA polymerase

How does a RNAP locate a specific gene? For instance, growth hormone has to be produced and the RNAP has to locate the gene. But the promoter (TATA box) will also be present infront of all cistrons. ...
1
vote
1answer
462 views

C Form DNA Base Pairs Per Turn

How does C-DNA have 9.33 base pairs per turn? The number of base pairs should be quantised. How can it be a decimal?
3
votes
2answers
8k views

What does this equation about DNA replication mean?

Could someone help me understand this equation please? I found it in a paper which said that it was DNA replication, but why? $\ce{dNTP + dNMP_{n} -> dNMP_{n +1} + PPi}$ I found that dNTP means ...
0
votes
1answer
243 views

What is a selectively neutral genotypic change?

I am reading the paper "Neutral evolution of mutational robustness". Because I am new to neutral evolution, I have a few questions. Firstly, from my understanding, genotypic neutrality means the ...
5
votes
3answers
329 views

Can we knock out Caspase-9 *and* avoid breast cancer phenotype in our mouse model?

I am trying to design a wet lab experiment with no wet lab experience to name. Right now, in my dream land, it would be excellent if it were possible to create a Caspase-9 knockout mouse (damage to ...
9
votes
4answers
241 views

Are there constraints on where intron/exon boundaries occur with respect to the triplet codons of the reading frame?

I did a quick search (here and elsewhere) and couldn't find anything on this subject. If all introns in a given primary transcript were spliced out in the same way, then this wouldn't matter. But ...
3
votes
1answer
2k views

Why increasing the vector concentration does not increase the effeciency of bacterial transformation?

I was reading some old description of the protocols used for the transformation of bacterial cells. In the description I read that the transformation works best with low amount of DNA, and if we ...
4
votes
3answers
2k views

Looking for good reference book in molecular biology [closed]

I am starting to work in molecular biology/ molecular genetic and I am looking for a really good book containing the main concepts and mostly the more recent techniques. I would be interested in a ...
3
votes
0answers
687 views

What metabolic processes do dormant and ungerminated seeds carry out?

What metabolic processes does a dormant embryo in a seed carry out? Seeds will not germinate, either because of a lack of favourable conditions, seed hibernation, or because of a genetically pre-...
2
votes
1answer
40 views

Which is the guideline to choose a molecular target to identify vertebrate hosts from arthropod bloodmeals?

There are some molecular targets to identify vertebrate hosts from arthropod bloodmeals including the Cyt b gene and the COI gene. Which are the standards or characteristics that I have to bear in ...
0
votes
1answer
618 views

Do restriction enzymes on read 3' to 5'?

Every chart of palindromic restriction enzymes I've seen lists their restriction sites from 5' to 3', something like this: EcoR1 cuts GAATTC between the G and A: 5' NNNGAATTCNNN 3' --> ...
3
votes
0answers
55 views

Should gene therapy safety protocol include isolation?

In the case of a gene therapy trial where viral vectors are used to deliver genes into mammalian cells, including humans, should biosafety and ethical protocols include isolation of the patient as a ...
6
votes
1answer
395 views

Is it possible to express a mutant gene only in a specific tissue?

Imagine that someone tries to develop a knockout mouse for a gene, but this result in lethality for the homozygous. Is it possible to express that mutant gene only in a specific tissue of interest to ...
3
votes
1answer
168 views

Why do genes with closely related functions often reside on different chromosomes?

Why do genes with closely related products are so often positioned on different chromosomes? To illustrate what I mean, here is an example from immunology: the invariant region of MHC is on ...
6
votes
1answer
97 views

“Enhancers” of enhancers?

I am looking for examples (if any) of genomic regions which regulates the activity of enhancers, either augmenting or reducing it. Essentially some kind of enhancers (or repressors) of enhancers to ...
5
votes
2answers
274 views

Why is 5S-rRNA is different from other rRNAs in place of transcription and usage of RNA polymerase?

While transcription of rRNAs happens in nucleolus mediated by RNA Polymerase-I, we see that 5S-rRNA is transcribed elsewhere by RNA Polymerase-III. What is the cause and why?
2
votes
0answers
55 views

Do The Traces Genetic Diseases Remain in families?

I know that there are certain diseases that are predominant on genes. But, is there any sort of surety that if parents are suffering from a disorder then their offspring has to suffer from the same. ...
2
votes
1answer
144 views

Markers for human genetic mapping

For human genetic mapping several different types of markers are used: RFLPs (Restriction Fragment Length Polymorphisms) VNTRs (Variable Number of Tandem Repeats) such as mini- and microsatellites ...
4
votes
1answer
58 views

What is the statistical relationship between radioactivity and mutation rate?

This question tries to narrow down the scope of that question. What is the statistical relationship between radioactivity and mutation rate? By how much would the mutation rate be lowered in a ...
9
votes
1answer
1k views

RNA migrating slower than DNA on Formaldehyde Gel?

So I ran into an interesting problem. I'm getting a linear DNA band that is twice as long (4x bases, but as denatured probably only 2x) as an RNA band running at the same size in a formaldehyde gel. ...
6
votes
2answers
161 views

Can molecular genetics make a boolean variable from a continuous variable?

In the same kind of idea than this question. Gene expression are regulated through complex interactions. The concentration of enhancers and repressors is an important aspect that dictate the level of ...