The process that produces a complementary strand of RNA from a section of DNA or (rarely) other RNA.

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Are single-celled organisms capable of learning?

I've read that the amoeba is capable of learning. Since these protists have no nervous system, it's safe to assume that even highly simplified learning mechanisms of the Aplysia are miles off in the ...
15
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2answers
266 views

Can methylation from DNA get copied to RNA during transcription?

Methylation on gene-body and 3'UTRs if copied to mRNA can potentially regulate post-transcription modifications or expression regulation. But I'm not sure if they are maintained after transcription or ...
12
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2answers
198 views

Modularity of transcription factors

I attended a seminar about neurogenesis that presented results for PAX6 as an important TF that contains 3 domains with very distinct patterns of downstream expression. The speaker ended up saying ...
11
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2answers
83 views

determining genome-wide exogenous binding of pathogens to host genome?

I've read this paper where they specifically modify a region in the rice genome to ablate the binding site of a pathogen, Xanthomonas oryzae, and disrupt the hijacking of a gene network in the rice ...
11
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1answer
603 views

How do CpG islands remain unmethylated?

In most of the genome CpG sites are pretty much always methylated, but CpG islands are instead often unmethylated. This has been linked to the fact that they often are associated to transcripted ...
10
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2answers
500 views

How does the genetic code evolve?

After looking at this question, some other questions poped in my mind. The DNA code is redundant, there are 20 amino acids for 64 possible nucleotide combinations. Therefore some amino acid are coded ...
10
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1answer
3k views

How does the stem-loop cause intrinsic transcription termination?

In this animation, towards the end (about three quarters) the process of transcription termination is shown. It states that the transcribed RNA forms a hairpin loop (or stem-loop), which halts the ...
9
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2answers
197 views

bi-directional transcription experiment

We suspect a bi-directional transcription event is happening at a locus in our organism where two genes are directly adjacent to each other. The annotation data is not well established. The intergenic ...
7
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1answer
87 views

Number of transcription factor genes in the human genome

What is the number of the transcription factor genes present in the human genome? Does this value differ compared to Mus musculus, Drosophila melanogaster, Arabidopsis thaliana, C. elegans and S. ...
7
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1answer
587 views

ChIP-seq vs ChIP-exo

I'm currently investigating ChIP-seq vs. ChIP-exo for finding binding sites. As far as I can tell, ChIP-exo seems to be better in every way than ChIP-seq... but then again, I'm not strong in this ...
7
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1answer
64 views

Which factors besides the thermodynamic stability are important for the hairpin in intrinsic transcription termination?

Intrinsic termination (rho-independent) relies on a stable hairpin with a subsequent uridine repeat. The common explanation on how these sequences cause the termination of the transcription are based ...
6
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4answers
490 views

How many transcription factors are there?

In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow (or transcription) of genetic information from DNA to ...
6
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3answers
77 views

Mutation That Loses Stop Codon

Someone asked this in my class and my instructor wasn't sure in her answer, doesn't anyone know what happens in protein synthesis if a mutation causes mRNA to not possess a stop codon? Would the ...
6
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2answers
99 views

How predictably will RNA polymerase not transcribe repetitive sequences?

I am working on an (expensive) synthetic construct, which happens to have many "repetitive" sequences within it that are integral to its function. Primarily, the two sequences that are worrying me ...
6
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4answers
728 views

Does RNA polymerase move around DNA or does DNA rotate benath the polymerase?

I'm thinking of the human genome specfically, but more general answers are welcome. As RNA polymerase moves along the DNA helix it follows a single strand. The two DNA strands are unwound locally ...
6
votes
1answer
309 views

Effect of histidine on the binding affinity of HisP

I was asked the following question by my teacher: A gene regulatory protein called HisP regulates the enzymes for histidine biosynthesis in the bacterium E. Coli. HisP is a protein whoes ...
6
votes
1answer
696 views

How much does the distance between a transcription factor binding site and a promoter influence transcription?

Assume we have a synthetic construct with a minimal (inducible) promoter that requires activation for significant transcription to occur. Realistically, how important is the distance between an ...
6
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1answer
1k views

Why does the T7 RNA Polymerase require a reducing environment ie. DTT

Every bloody protocol suggests adding in DTT when doing in vitro RNA transcription. Why? The rationale seems to be that the cytoplasm traditionally has a reducing environment but as the only protein ...
6
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1answer
238 views

How can promoter binding sites be determined?

I have been trying to find out which sigma factor is responsible for the transcription of RNA polymerase subunits $\alpha$ (rpoA) and $\beta ^{\prime}$ (rpoC) in Bacillus subtilis. I would expect it ...
5
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2answers
851 views

Why is the DNA codon table “equal” to the RNA codon table

Before anything else please pay attention of the double quotes on the "equal" in the title - I know they are not equal, but you will understand in a bit. If I look at the DNA codon table here or in ...
5
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1answer
70 views

How can I tell if regulation is at the transcriptional or translational level?

I was reading a paper, http://www.pnas.org/content/109/8/E471.short, where the authors claim that (e475) Translation of the TfR (Transferrin Receptor) is regulated through sequences in the 3′ and ...
5
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2answers
95 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 ...
5
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1answer
2k views

Transcription and translation of prokaryotic operons

I'm taking a molecular genetics course, and we're currently discussing prokaryotic operons. The lacZ operon came up frequently for me as an undergraduate as an example for teaching regulatory control ...
5
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2answers
54 views

tools to reconstruct the transcriptional regulatory circuits?

What are commonly used tools to reconstruct the transcriptional regulatory circuits that govern diverse cellular responses and what input data sets do they accept?
5
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1answer
62 views

How do biologists infer correct ORF of a DNA sequence?

Each DNA (RNA) sequence has 6 possible Open Reading Frames(ORF). My question is: What are the theoretical bases of in vitro or in silico tries to find correct reading frame of a sequence? Is it just ...
5
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2answers
49 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?
5
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1answer
144 views

Mechanism of Muscle Growth

According to this video (sorry for the poor reference but it represents my level of understanding in physiology), muscle grow as a consequence of repairing micro-lesions. How are these micro-lesions ...
4
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2answers
2k views

On which strand does the promoter sit?

My book keeps giving different indicators as to whether the promoters are on the coding or template strand. It says the -35 region in prokaryotes must be on the coding strand. It also mentions, that ...
4
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1answer
185 views

Bacterial chromatin binding data?

I'm looking for data - maybe CHP^2 data that shows chromatin binding to a prokaryotic genome under some specific conditions. Can anyone point me to a source?
4
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1answer
89 views

What is the relation between plasmid concentration and mRNA levels?

Suppose a simple synthetic construct, consisting of a constitutive promoter and a single gene: One of the simplest ways to model GFP transcription is to use an ODE: $\frac{d [GFP_{mRNA}]}{dt} = a - ...
4
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1answer
75 views

Transcriptionally-mediated DNA damage

I'm researching the genetics of brain cancer, and finding a huge number of mutations in voltage-gated channels. It stands to reason that some of this DNA damage is due to the DNA being transcribed ...
4
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1answer
47 views

Location of TFBS in genome

I have an annotated set of SNPs and I would like to explore the difference in the binding affinity of the transcription factor (TF) if I have a SNP in my locus. As my SNPs are annotated (I know wether ...
4
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1answer
90 views

Why are most transcription factors enhancing the expression rather than repressing?

One can classify the effects of Transcription Factors (TF) on gene expression into two types: it either enhance or repress the gene expression. I have always been told that most of transcription ...
4
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1answer
93 views

What triggers DNA to produce proteins?

What is the trigger for DNA to produce proteins or RNA? I have found enough material to study the inner workings of the cell and DNA; but, I can't find an explanation of the mechanics the cell uses ...
3
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2answers
52 views

RNA polymerase question

In this question we are examining a bacterial RNA polymerase that elongates at 20 codons per second. Question 1: How long will this RNA polymerase take to transcribe the Lac Z gene at 3510 base pairs? ...
3
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3answers
82 views

Can genes that activate transcription factors also called be called transcription factors?

If the sole known function of a gene is to activate a transcription factor, would that gene also be considered a transcription factor, or is there a word for such genes that are further upstream on ...
3
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1answer
61 views

How can I re-format my DNA motifs' position weight matrices?

I am working with a set of DNA motifs that are predicted as potential regulatory motifs (e.g. transcription factor binding sites). The motifs belong to several species, and I wanted to cluster these ...
3
votes
1answer
160 views

Remove RNAse from pipettes?

Our lab uses old Gilson Pipetman pipettes. I've been using some for making mRNA by in vitro transcription and started running into RNAse issues. I'm trying to clean everything up, including the ...
3
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1answer
48 views

Process of Transcription

During the process of Conversion to Ribonucleoside Monophosphates the various ribonucleoside triphosphates break off their high energy bonds after linkage to the DNA.But the first ribonucleotide ...
3
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1answer
31 views

Is RNA polymerase affected by proteins bound to the coding sequence of a gene?

I am designing a synthetic gene construct to express genes in E. coli driven by either Ptet or PLacO. The construct would look like: -Ptet-(Gene1)-PLacO-(Gene2)- I want to express each gene using ...
3
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1answer
80 views

mRNA with Pseudouridine and 5-methylcytidine?

I am making mRNA by in vitro transcription for transfection purposes. There is a lot of literature about how protein expression is increased and innate immune activation is decreased by substituting ...
3
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0answers
14 views

Gene silencing: relative or absolute number of methylated CpG sites?

CpG content varies a lot across the human genome. What does determine a promoter to be silenced through DNA methylation: the fraction of CpG sites that are methylated or the total number of methylated ...
2
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1answer
74 views

How does alternative splicing work?

I am trying to find out what controls what exons are spliced out, and I keep coming across the term cis regulator, but I cannot seem to find a clear explanation of what happens... Thank you in ...
2
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1answer
125 views

DNA methylation on the forward vs reverse strand?

I'm wondering if there are meant to be differences in DNA methylation between the forward and the reverse strand of the gene? I'm wondering because in primer design for bisulfite pyrosequencing one ...
2
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1answer
829 views

How is the transcription direction of RNA polymerase determined?

When transcription factors attach to the DNA strand - How do they know in which direction they have to initialize the transcription by rna polymerase? Is it always read in the same direction anyway? ...
2
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1answer
30 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 ...
2
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3answers
462 views

Why isn't there a standard unit of promoter strength?

Sometimes in synthetic biology, we need to know rates of transcription of one promoter in relation to others (particularly inducible vs constitutive) in order to perform tasks like balancing ...
2
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2answers
505 views

Transcription factor binding site located in intron

I have noticed that some TF binding sites are located in the introns of the genes. I am puzzled about whether the TF only binds to DNA in the initiation stage of transcription and will detach during ...
2
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1answer
23 views

Are both (partial) copies of DNA transcribed in S and G2 phases of cell cycle?

For a little less than half the cell cycle, a significant number of genes are represented twice (just before dividing). Does the cell differentiate between these DNA in any way or are transcription ...
2
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0answers
40 views

Multiple transcripts encoding for one protein

Trying to get a better understanding of the process of DNA to proteins. So when we have a gene, it is read from the 5' to 3' end, only translating the exons to mRNAs. A single gene can have multiple ...