RNA blot (Northern)

The RNA blot or Northern blot (named after the DNA blot (Southern) for genomic DNA fragments) is a molecular biology technique used to separate and identify pieces of RNA. RNA molecules are separated by mass on a gel, transferred (blotted) onto a cellulose or nylon membrane, and then labelled with complementary DNA or RNA molecules. These probes are either radioactive, typically ³²P, or contain labelled nucleotides, e.g. DIG-dNTPs, recognisable by antibodies. RNA molecules can be detected and roughly quantified via probe hybridisation.

For a schematic overview of the method see here.

Designing RNA probes

• DNA probes, esp. using DIG-antibody detection, often give no/weak signal; RNA probes often better here [1]
• minimum probe length around 25 nt (anybody has a reference for this?) [2]
• DNA probes may be usable for both qRT-PCR and RNA blots [3]

Lab-specific protocols

• Endy:Northern Blot, 32P End-Labeled Probes
• Endy:Northern blot, AlkPhos end-labeled probes

See also

• RNA
• RNA Extraction
• RNA electrophoresis
• BE.109:Systems engineering/Measuring DNA, RNA, protein

External links

• RNA blot protocol for cells in culture, complete with materials (1999) by Howell lab, UCSD
• detailed RNA blot protocol for DIG probes (2000) by Arnoud van Vliet
• archived protocol conversations from Protocol Online
• index of RNA blot protocols from Protocol Online
• RNA preparation and blotting protocol (2006) by Kelly lab, Washington Uni
• RNA blot protocol by Allen Gathman from Southeast Missouri State Uni
• The basics of RNA blots, Ambion general article
• Techniques to detect mRNA - includes RNA blot, Ambion TechNotes
• Pack insert DIG RNA detection kit, Roche
• Probe hybridization protocol - Parker lab (don't know how many stars to give it!)