Labeling of miRNA probes - (Mar/14/2007 )

Hello everybody,

I plan to perform Northern Blots with siRNAs from plant tissue.
For detection of the miRNAs (~21nt length) I'll design probes that are end-labeled.

Has anybody an idea or protocol for radioactive end-labeling of small RNA probes?

Thanks a lot!

For labeling of DNA oligo and small RNA, I use T4-polynucleotide kinase and followed its mannual , by the way, for small RNA, it is better dephorosphorated before labeling, Ambion used to provide a kit for such label including dephorosphorate reagent and reagent for inactive dephorosphorate reaction...
Following is a paper included an introduction for labeling of small RNA and DNA oligomers
Hutvagner G, Mlynarova L, Nap JP.
Detailed characterization of the posttranscriptional gene-silencing-related small RNA in a GUS gene-silenced tobacco.
RNA. 2000 Oct;6(10):1445-54.

I will try the Ambion Kit ,I think. Thanks so far.

So does anybody know, which miRNAs are constitutively expressed in A.th.