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

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No digested product bands, but markers are visible. What could be the reasons?

I had to digest my insert containing plasmid and another vector into which my insert has to be ligated, each with BamHI and NotI. Upon digestion, I ran the gel to check for results. The digestion ...
4
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1answer
80 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 ...
4
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3answers
62 views

Hebbian theory “fire together” clarification

Donald Hebb states it as follows: "Let us assume that the persistence or repetition of a reverberatory activity (or "trace") tends to induce lasting cellular changes that add to its stability.… ...
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19 views

Cross section of actin network in neurites

for a simulation I am developing I would like to know how the actin network in neurites is distributed. Is actin confined to the periphery or is the whole neurite shaft containing actin with a rather ...
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2answers
34 views

What are some atypical examples of positive transcriptional cooperativity?

Cooperativity in gene expression is an important feature of many regulatory networks. Described using the Hill function, the most common example is a transcription factor (TF) that when bound to its ...
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28 views

Has anyone used Crispr/Cas to induce a knock-in in MEF cells?

Does anyone have experience with the crispr/cas9 platform performed on MEF? Or does anyone recall any relevent articles? Thanks
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115 views

High frequency human genetic oscillators?

The most well studied genetic oscillators in human genomes are involved in regulating the circadian clock (which operates on an approximately 24-hour cycle) and cell cycle activity (with single cycles ...
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42 views

RNeasy Mini Kit low 260/230 ratio — can I purify this RNA for further use?

I used Qiagen's RNeasy Mini Kit to isolate RNA from 5*10^5 C28/I2 (immortalized human chondrocytes). However, my yield is low (~25 ng/ul), but my 260/280 ratio is great (~2.3), and my 260/230 ratio is ...
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18 views

coevolution by physical interaction between RNA sequences

There are several items that relate to the concerted evolution between pairs of sencuencias (especially structural) rRNA as a consequence of physical interaction in tertiary, or even quaternary ...
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17 views

detection of primary origin (natural selection or genetic drift) on alterations in sequences

I recently had a question about how to distinguish the origin of variations in the sequences of rRNA as to whether alterations are generated by genetic drift or natural selection. For me it has not ...
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1answer
508 views

Lyonization and X-linked disorders?

Lyonization or X-chromosome inactivation is the conversion of all but one, X-chromosomes in Females into non-coding heterochromatin (i.e. deactivated) leading to the formation of one or more Barr ...
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113 views

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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105 views

Optimization of annealing temperature

I am trying to optimize annealing temperature for some primer pairs. I have tried optimization using cDNA, genomic DNA, Taq polymerase, phusion polymerase etc., but every time I am either getting ...
3
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25 views

Efficiency of plasmid DNA isolation from frozen E. coli cell cultures

Has anyone isolated plasmid DNA from frozen (at -20degrees) E. coli cell cultures (not pellets)? Has that worked and if so, with what yields? What would be the quality of the isolated plasmid DNA if ...
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28 views

Assembling DNA fragments with ~10kb overlap in vitro

Let's say I have two fragments of bacterial DNA (~50kb in length each) that overlap on the ends by roughly ~10kb; the overlap sequences are unknown. I would like to assemble these into longer ...
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11 views

border zone of the infarcted heart

I did myocardial infarction experiments on mice and I am a newbie in this area. I need to isolate RNA and protein from the remote and the border zone. Where should I cut the heart so i can separate ...
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3answers
42 views

FRET only works for interactions between 1nm to 20nm.

FRET only works for interactions between 1nm to 20nm. How can you be sure that the interaction that you want to study isn't less than 1 nm/greater than 20nm apart?
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1answer
24 views

Heterochromatin production limitations

Currently playing with some ideas for a project and needed some guidance. I am wondering, both in Drosophila melanogaster and in general, is the amount of heterochromatin a cell/nucleus can produce ...
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26 views

Kinesin-5 / cytoplasmic dynein spatial density distribution in neurons

is there some way to experimentally determine the density distribution of those two molecular motors in a Neuron? Fluorescence labeling would be impossible(?) as GFP markers would probably alter the ...
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2answers
68 views

Theoretically, what technique would one use to modify a virus so that it only affected a subset of the population?

I'm writing a novel and i would like to know some of the equipment and techniques involved with modifying a virus. Is it feasible for a virus to be engineered to only affect certain people? It ...
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3answers
88 views

What equipment would one use to modify a virus? [closed]

Would anyone be so kind as to give me a few examples of the equipment involved when modifying a virus? Otherwise my novel may end up reading Eva entered the lab and modified a virus. Not much back ...
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1answer
236 views

How tolerant are ants to cold?

There was a trail of what are commonly known as sugar ants (small, brown, hyperactive) in my kitchen. Three of them walked onto an ice tray placed in their path. They only walked a short distance on ...
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1answer
72 views

Do mitochondria use ATP in order make another ATP from glucose?

Do mitochondria use ATP in order make another ATP from glucose, or does it use another source of energy to convert glucose to ATP?
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17 views

What models are used for the different pathways of apoptosis?

We are trying to find references for experimental models of different pathways of apoptosis (caspase-dependent and -independent intrinsic apoptosis, death receptor type-1 and -2 mediated apoptosis, ...
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732 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?
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23 views

Is it possible to synthetically replicate the results of cryptobiosis? If so, how?

Okay if my question seems ridiculous I apologize because I have next to no knowledge of synthetic biology and what the field is capable of doing and it's methods and methodology. Take a organism ...
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1answer
82 views

What are the lifetimes of cellular components on organelle or molecular level?

I was thinking that even though I know how generally the cell works, I don't really have a feeling of how volatile it is. I want to know what is the lifetime/turnover rate of different constituents of ...
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1k views

Difference in length of Okazaki fragments

The length of Okazaki fragments in the lagging strand is about 100-200 nucleotides in eukaryotes and about 1000-2000 nucleotides in prokaryotes. What (molecular mechanism, enzyme type ) ...
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40 views

difference between ischemia and oxygen-glucose deprived medium

Ischemia is roughly defined as insufficient blood flow to a specific region of the body and in the literature it is generally considered as causing oxygen and glucose deprivation in the tissue and ...
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2answers
3k views
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1answer
116 views

Why Isolated, recombinant plasmid DNA without any restriction is often detected in agarose gel electrophoresis as three DNA bands?

I don't understand why three bands are found without any restriction digest. Please answer me as soon as possible. Thank you
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1answer
47 views

What is Pan for in pan-caspase?

A simple question (I could not find it on internet): What is Pan for in pan-caspase? Is it any different from the term 'caspase' ?
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2answers
65 views

Single stranded DNA in gel electrophoresis

From http://www.nfstc.org/pdi/Subject05/pdi_s05_m01_01.htm : ... The separation medium contains a denaturant in order that the electrophoresis is conducted on single-stranded DNA fragments. ...
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63 views

What is the definition of a stringent/relaxed plasmid?

I have found a publication which proposes some definitions, including a definition for strict and relaxed replication. The definitions are: Relaxed control of plasmid replication. Relaxed control ...
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1answer
75 views

Are there any organisms that lack ATP synthase?

ATP synthase is used by cells to synthesise ATP from ADP using energy from a proton gradient. Depending on which sites I look at, this is either a universal feature of living cells, or it's "almost ...
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2answers
97 views

A photosynthesizing mouse?

N. Shubin's Your Inner Fish makes the point several times that there is a lot of functional similarity between some seemingly remote gene cousins. If that needed reinforcing we have the spider-goat, ...
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24 views

Property of E.coli harboring F element

From Genetics by Ursula Goodenough E.coli harboring an F element are endowed with a number of phenotypic traits : 1.They are sensitive to infection by ssRNA phages and certain ssDNA phages. ...
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1answer
52 views

What is “bacto” peptone?

Standard recipes for yeast medium often include "bacto-peptone". Is this the same as bacteriological peptone? Is there an authoritative source that spells it out?
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1answer
48 views

How was Restriction Site of EcoRI sequenced?

The sequence of restriction site of EcoRI - GAATTC was identified in the early 1970s, before Sanger Sequencing was invented.(1977) How was the restriction site of EcoRI sequenced ?
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6answers
161 views

Sequence analysis software suites

I have used DNAStar laser gene and VectorNTI in the past for cloning, primer design, sequence alignments, etc but no longer have access to these. Are there any comparable replacement suites or what ...
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1answer
57 views

What is a phospho-protein binding domain?

Is this just a domain that binds proteins that have been phosphorylated? And it mediates signalling between an activated/phosphorylated protein? How is this significant with BRCA1?
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27 views

PQR files make from pdb2pqr are different to GROMACS

I have a pdb file and I would like to make a pqr one. In GROMACS, I use editconf -mead to produce pqr, with topol.top taken from pdb2gmx or use it to produce pdb file, then use pdb2pqr. Which one is ...
2
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1answer
30 views

Trimming of tRNA precursors

From Molecular Biology of the Cell (4th edition) by Bruce Alberts et al. (Chp 6, Pg 338) : Both bacterial and eucaryotic tRNAs are typically synthesized as larger precursor tRNAs, and these are ...
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29 views

What is the suitable terminology to describe this study approach?

I need to know the correct term(s) which are usually used in the parlance of both biology and bioinformatics for this study approach: About 11 transcripts were investigated using qPCR for a number of ...
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1answer
57 views

A question related to qPCR analysis

Here is the thing. I am using a method, called TU-Tagging, to isolate cell type specific RNA. You can find more about the method here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2783170/ To explain ...
3
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1answer
100 views

Do macrophages engulf mtDNA?

Let us assume that in a human body, a mitochondrial DNA is released to extracellular environment. We know that mtDNA inheritance is solely matrilineal. So the question is, If your mitochondrial DNA ...
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2answers
267 views

Signaling through G protein Coupled Receptors?

There are two different cell lines but we do not know that these cell lines have Gs or Gi proteins, associated with their G-protein coupled receptors. If we wants to know about this. Can we design a ...
4
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1answer
104 views

how is the plasma membrane repaired after endocytosis?

When the vesicle is swallowed of course the lipid layer internalizes. My question is how will the top segment of membrane will bind back together when that vesicle took the membrane with it inside ...
2
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1answer
36 views

H O N C alternatives for organic life?

Most organic structures built from hydrogen, oxygen, nitrogen and carbon. They are represent 1-,2-,3-,4- bond relations (chemical valence) which allow to build variety of chain structures. Are there ...