SnRNA/snRNP, involvement

Both methods involve swelling of the cells in hypotonic solution, disruption of the plasma membrane, and extraction of the nuclei in a high salt buffer. The extracts support a number of nuclear functions and have been extremely useful in studying transcription and splicing (see Section 5.1). Nuclear extracts are also a useful starting point for purification of snRNAs, snRNPs, hnRNP proteins and SR-proteins (Section 3.1.2). 

Small nuclear ribonucleoproteins contain small nuclear RNAs (snRNAs)known as Ul, U2, and so onwhich are complexed with proteins to form the snRNPs. The snRNPs recognize specific nucleotide sequences on the nascent transcript and bind to the transcript. Those snRNPs that are involved in RNA splicing form a complex called a spliceosome that removes introns from the nascent transcripts. The spliceosome is nearly as large as a ribosome. 

Small nuclear RNA (snRNA) is found in the eukaryotic nucleus and is involved in splicing reactions of other RNA types. An snRNP is a small nuclear ribonucleoprotein particle. A complex of small nuclear RNA and protein catalyzes splicing of RNA. 

Small nuclear RNA (snRNA) molecules form part of the spliceosome that is involved in cleaving introns out of mRNA precursors. There are five of these special suRNAs, called U1, U2, U4, U5, and U6. They range in size from 50 to 200 nucleotides and form complexes with proteins to form small nuclear ribonucleoprotein particles (snRNPs). 

U snRNP An RNA protein complex consisting of midme-rich small nuclear RNAs (U snRNAs) complexed with a common set of proteins, the Sm proteins, and U snRNA-speciflc proteins. TheUl, U2, U4, U5, and U6 snRNPs are involved in RNA splicing. Other U snRNPs serve other functions in the cell. 

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