Can RNase A degrade miRNA? - (Aug/02/2007 )
hypothetical situation:
you lyse some cells using a typical lysis buffer such as Tris, NaDOC, triton and you add RNase A to the cell lysate and incubate at 37C for a period of time. Would you be able to see a decrease in miRNA levels?
If miRNA is still in the duplex form, it is very stable and resistant to RNase. If miR/miR* have disassociated, I guess they are equally sensitive as any RNA to RNase.
Hi Fred,
I don't remember where I read that, but I searched google and one item has the following précis:
Introduction to Modern Virology - Google Books Result
by Nigel J. Dimmock, Sandy B. Primrose - 1994 - Science
When RNA is extracted from infected cells, a ribonuclease (rnase (-resistant fraction can be isolated, which is double-stranded RNA. This rnase-resistant ...
books.google.com/books?isbn=0632034033...
thank you very much
i'll try a look at that 
I think that mature miRNAs may show some degree of resistance to RNAse mediated degradation, as they could be protected by the RISC.
miRNA in duplex form? you mean the pre-miR with the stemp-loop? Or do you mean after DICER cuts the pre-miR?
pir miR cutted by drosha... pre-mir cutted by dicer. dicer gives productswhich are double stranded before loading into risc complex
As far as I know, the product of DICER being double stranded is just hypothetical at this point in time. I haven't seen anyone being able to purify "double stranded" mirna.
I have also seen this in my experiments. All the mirna you get from an RNA extraction is single stranded.
Did you read about it in some publication? Please give me the reference. I would be interested in reading it.
I remember a kit provide by SBI, which aims to clone miRNA in form of double strands , but not sure the efficiency of the approach