snRNPs: Methods for Purification


Small nuclear ribonucleoprotein particles (snRNPs) are essential cofactors for the nuclear splicing of pre‐mRNA introns. The method best suited to the purification of snRNPs is affinity chromatography combined with competitive elution.

Keywords: snRNP; pre‐mRNA splicing; chromatography; RNA–protein interaction

Figure 1.

Glycerol gradient centrifugation of snRNPs. snRNPs eluted from an anti‐m3G column were loaded on a 10–30% glycerol gradient and centrifuged in a Beckman SW 28 rotor for 16 h at 27 000 rpm. After fractionation the proteins were extracted and separated by electrophoresis on an SDS–polyacrylamide gel. The migration of the individual snRNAs is indicated at the bottom of the figure. The bands corresponding to the common proteins are marked on the left, and on the right the approximate molecular masses of several specific proteins are indicated. The Coomassie‐stained gel was kindly provided by Axel Badouin.



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Further Reading

Kastner B (1998) Purification and electron microscopy of spliceosomal snRNPs. In: Schenkel J (ed.) RNP. Particles, Splicing and Autoimmune Diseases, pp. 95–140. Berlin: Springer Verlag.

Krämer A (1990) Purification of small nuclear ribonucleoprotein particles active in RNA processing. Methods in Enzymology 181: 215–231.

Will CL, Kastner B and Lührmann R (1994) Analysis of ribonucleoprotein interactions. In: Higgens SJ and Hames BD (eds) RNA Processing. – A Practical Approach, vol. 1, pp. 141–177. Oxford: IRL Press.

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How to Cite close
Kastner, Berthold(Apr 2001) snRNPs: Methods for Purification. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0002605]