Micro RNAs in disease and disease diagnosis

[Le Pom]

I'm doing an essay on miRNAs.

It is quite a new topic in research and the first miRNA was discovered in only 1993.

I wondered if anyone knew anything about them or would care to share any knowledge they have?

[Airtones]

I would definately look into RNA interference (RNAi) as they both essentially occur by the same mechanism and the literature is a bit better for RNAi as siRNA is a pretty common laboratory technique for producing partial knockouts (knockdowns).

An endonuclease, 'Dicer', takes up short dsRNA with the help of a protein called TRBP. The hetrodimer cleaves it into 21-23bp sections and then passes it to argonaut proteins like Ago2 which grip the dsRNA between their PIWI and PAZ domains. They then strip off the passenger strand and use the remaining strand to bind and cleave complemtary mRNAs as they leave the nucleus, between the 11th and 12th peptide bond off the top of my head. They then dissociate the cleaved passenger strand and bind another complementary mRNA and do it all over again.

Net effect is a reduction in the effective translation of that mRNA (since its been chopped in half). I believe there might also be some research now about pre-translational gene supression being caused by miRNA but thats new to me.

[Le Pom]

yes, well, i would look into RNAi but I am focusing on the biogenesis of miRNA and its role in disease.

Therefore i look at drosha and dicer along with the microprocessor complex when looking at miRNA maturation.

Now the thing is, research into diseases are so new, and am actually struggling with how miRNAs aid diagnosis?

[Airtones]

I just threw in miRNA and Diagnosis into a pubmed search and got a few leads back.Is this the sort of thing your after?

MicroRNAs (miRNAs) are noncoding RNA molecules of 21-24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNAs play essential roles in embryogenesis, cell differentiation, and pathogenesis of human diseases. This study describes a comparison between the miRNA profile of kidney biopsies from lupus nephritis (LN) patients and the controls, to develop further understanding of the pathogenesis of LN.

[Le Pom]

well yes, that is kind of along the lines of what i am researching, that is more clinically based than biochemically base though, but the bit about understanding pathogenesis is good, as thats what my research is lacking.

[Pammy]

Why don't you do a PubMed or Medline search...just use a variety of keywords that might give you what you want? There's bound to be infinite literature so I'd restrict it to reviews in the first instant...

[Le Pom]

oh its ok, i already did that and done my essay, i just wanted to know what other people knew on the subject.
I used over 40 articles to write my essay. Was long, but enjoyed researching this ever so new topic.

[Pammy]

Oh cool, well then you probably know more about it than anyone else on here!
I did my biochem degree before these topics became such hot research...hence I know virtually nothing about them :-)

[Le Pom]

oh really? when did you do your degree?
miRNAs were discovered in 1993. But only really in the past 5 years have they become deeply researched into.

[Pammy]

Yeah that makes sense, I graduated in 2002...and then moved into a very, very different area!