Questions tagged [microrna]
Micro RNA (miRNA) are a class of small (22 nucleotide in the mature form) non-coding RNA. They are present in plants and animals and function as transcriptional and post-transcriptional regulators of genes. They bind to a complementary region in the transcribed gene to form doublestanded RNA molecules. These are silenced since they cannot be translated and often subsequently degraded by the cell.
33 questions
1
vote
0
answers
54
views
Length of base-pairing required in Argonautes
I've been reading a lot about Argonautes and its recognition mechanism and how there are some differences on how they match the target RNA.
I know that the (mi)RNA guides are quite longer than what is ...
1
vote
0
answers
42
views
Could you recommend literature regarding non-coding RNA and micro RNA? [closed]
I am familiar with the Alberts and Watson textbooks, but they are quite general, not specific.
I would be grateful if you wrote down books or even in-depth reviews/papers regarding the topic.
0
votes
1
answer
45
views
Relationship of disease to alternative strand - microRNA-3p or -5p
I am working in a project involving microRNAs in a cohort of patients (controls and cases of coronary artery disease). I got results from sequencing of HDL-lipoprotein involving diferentially ...
2
votes
2
answers
214
views
Why do cells use microRNA to break down mRNA, instead of not transcribing it in the first place?
As I understand it, microRNAs are used to ensure that certain genes are only expressed when needed. The way this apparently works is that when the translation products of an mRNA are not required the ...
0
votes
1
answer
94
views
Why does miRNA not get translated?
If miRNA and mRNA are made of the same nucleotides, then why are miRNA not translated like mRNA?
Is it due to miRNA lack of start codon? Or lack of promoters?
Has it got anything to do with RISC?
0
votes
0
answers
39
views
Relative abundance and action of 5p and 3p microRNAs
I am a beginner in genetic research and am currently conducting a project concerning microRNAs. Let's say we have miR-1-5p. If miR-1-5p is upregulated in a disease, will miR-1-3p always be ...
4
votes
0
answers
32
views
How can I search through literature databases for words containing a * when the asterisk is read as syntax and not part of a query?
I'm exploring the literature on microRNA, where it is common for the less utilised strand of the miRNA duplex to be referred to as the miRNA* strand.
However, I am experiencing some issue searching ...
0
votes
1
answer
43
views
How to confirm secondary structure formation of Precursor miRNA on gel?
I want to fold precursor-miRNA into its secondary structure and then confirm it on gel. At first, I heat it in annealing buffer at 95°C for 5 minutes and cool down slowly. Then I run it on gel but the ...
1
vote
1
answer
88
views
Are microRNAs transcribed from the same DNA strand as their parent messenger RNAs?
I am new to micro RNAs. I have been trying to find the answer to the question if microRNAs are transcribed from the same DNA strand as the messenger RNAs encoded by the encompassing gene?
From the ...
3
votes
1
answer
237
views
Which mRNAs enter P-bodies?
Processing bodies (P-bodies) are distinct foci within the cytoplasm of the eukaryotic cell consisting of many enzymes involved in mRNA turnover (ref). They play a fundamental role in RNA silencing/...
3
votes
0
answers
4k
views
What is the difference between "dysregulation" and "deregulation" of miRNA?
I've started to study the role of miRNA in cancer. Wikipedia says:
Just as miRNA is involved in the normal functioning of eukaryotic
cells, so has dysregulation of miRNA been associated with ...
4
votes
1
answer
340
views
What is cognate miRNA?
I understand what miRNA are, but I'm unsure of what cognate means. Looking at this post, it seems that a cognate miRNA is a known miRNA vs. a recently discovered/possible miRNA. Is this thinking on ...
1
vote
1
answer
121
views
Why are there two mature sequences of microRNAs in miRBase entries?
In the miRBase database entries generally show a stem loop sequence and two mature sequences. For example the entry for hsa-mir-15a gives three sequences: (1) the Stem-loop sequence hsa-mir-15a, (2) ...
2
votes
1
answer
182
views
Do all microRNA isoforms need to be known and sequenced to obtain microRNA expression?
From what I understand, microRNA are short "hairpin" shaped nc structures. When sequencing and counting miRNA, isoform miRNA are "found" which are subsections of varying length and possibly with some ...
1
vote
1
answer
448
views
Can a miRNA be upregulated and downregulated in the same disease
I am computational guy and hence apologies if the question is silly.
Can the same miRNA show upregulation and downregulation in the same disease? (Not in the same experiment, though). For e.g. can ...
1
vote
1
answer
113
views
What is the difference between hsa-miR-33a and hsa-miR-33b?
Does anyone know what is the difference between two miRNAs like hsa-miR-33a and hsa-miR-33b? The last letter in them shows what?
Also, if we know that hsa-miR-33a targets gene A, can we say that hsa-...
3
votes
2
answers
3k
views
Small non-coding RNA (sRNA) vs. micro RNA (miRNA)?
What are the differences between micro RNAs (miRNA) and small non-coding RNAs (sRNA)? Are these two terms used interchangeably?
0
votes
1
answer
420
views
Converting miRNA names
I need to convert all of my microRNA names e.g. hsa-miR-30e-5p to e.g. entrez gene IDs, ensemble IDs or another ID. Does anyone know a good ID conversion tool for microRNAs?
(I managed to convert it ...
3
votes
3
answers
152
views
miRNA targets mRNAs
If we observe that a miRNA, say hsa-mir-233, targets a mRNA, say XXX, in a given tissue in disease condition, can we say that always hsa-mir-233 targets mRNA XXX regardless of type of tissue and ...
1
vote
1
answer
111
views
Difference between micro RNA and short-interfering RNA and CRISPR Cas 9 system?
I read this article https://www.quantamagazine.org/20150206-crispr-dna-editor-bacteria/ and am slightly puzzled as to why the CRISPR/Cas 9 system is seen as being so revolutionary. It seems like the ...
10
votes
3
answers
3k
views
Are non-coding RNAs introns?
I am slightly confused as to what part of the genome codes for non-coding RNAs. Is it the introns? This would make sense to me as to why they are not transcribed as the introns are not transcribed. Or ...
2
votes
1
answer
92
views
What is the silencing mechanism of AGO1,AGO3 and AGO4?
I read that this proteins lack of slicer activity, so what mechanism do they use to perform gene regulation?
4
votes
0
answers
178
views
What is the meaning of conservation site in miRNA-mRNA pairing context?
I am not biologist and just work in Bioinformatics field.
Does anyone know what is the meaning of conservation in the context of miRNAs and their pairings to mRNAs?
Example:
Each of these duplexes ...
7
votes
2
answers
635
views
Naming convention of miRNAs
I'm trying to understand naming convention of miRNAs. I've found the wikipedia article about it nomenclature Based on it, I try to figure out what is hsa-let-7a. As far as I understood, hsa refers to ...
4
votes
2
answers
639
views
Relative microRNA comparison from from TCGA data?
I have a conceptual question that I was hoping someone could answer.
Can I say that microRNA A is expressed x-fold greater than microRNA B directly from the TCGA miRseq data? Can I do this after ...
2
votes
1
answer
841
views
what the best E-value cutoff in the miRNA homology search
I'm trying to use miRBase database to annotate some microRNA sequences in length 22-24bp. I highly appreciate if someone let me know whether I should do this BLAST against mature miRNA or stem-loop ...
9
votes
2
answers
5k
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
1
answer
45
views
Periods of Heavy Speciation
I have a set of microRNA ages with corresponding labels suggesting which clade they first emerged from. For instance, for hsa-mir-1, let's say, it would have an age of Eutheria. I have several peaks ...
1
vote
1
answer
57
views
Why are different lengths of nucleotides taken for structure prediction from an miRNA match area after BLAST analysis?
Generally in miRNA prediction most researchers do as Blast search with a set of miRNAs downloaded from miRBase with the parameters they require. Later on usually custom methods are utilized to get an ...
2
votes
1
answer
236
views
Steps to confirm if predicted miRNA is good or bad
I aligned all miRNAs available to the supercontigs of a particular genome with certain parameters (e value of 0.01 and a word match of atleast 7 as suggested in this paper). I have also isolated the ...
3
votes
1
answer
835
views
mFOLD prediction result interpretation
I am trying to predict the secondary structure of certain predicted pre-miRNAs through mFOLD which is the generally accepted technique for structure prediction in most studies. I am finding it hard to ...
0
votes
1
answer
40
views
Known MicroRNA - Gene Systems?
Have there been any experimentally-verified systems of microRNAs targeting a gene set (e.g., in cancer, perhaps)?
7
votes
1
answer
75
views
circulating microRNAs are functional?
In plasma and other body fluids, miRNAs can be found. They not only originate from dying cells but also from active secretion and are usually 'packed' into vesicles/lipo-proteic structures (i.e. ...