ASF/SF2 (SFRS1 or SRp30a from E. Coli)

 ASF or called SF2, a member of the SR protein family, is an essential pre-mRNA splicing factor required for both single and alternative splicing (1-3). Phosphorylation on serine residues located within the SR domain directly regulates ASF/SF2 activity and compartmentalization of other SR splicing factors (4, 5). In addition to interacting with RNA and other splicing factors, such as U1-70K, U2AF and other SR proteins, ASF/SF2 also directly or indirectly interacts with HIV regulatory protein Rev, the C-terminal domain (CTD) of the largest subunit of RNA polymerase II, and numerous transcription factors, thereby suggesting a potential role of ASF/SF2 in coordinating of transcription and pre-mRNA splicing (6, 7).

Recombinant ASF/SF2 protein can be used for: 1) in vitro function studies including pre-mRNA splicing, cross linking and other RNA binding assays; 2) protein-protein interaction assay; and 3) cell growth and proliferation assays.

The purified protein is greater than 95% homogeneous based on SDS-PAGE analysis.
1 unit equals 1 nanogram of purified protein. 1-5 units are sufficient for a gel mobility shift assay in a 20 µl reaction, 100 units are sufficient for a protein-protein interaction assay and 100-500 units are required for a splicing assay in a 20 μl reaction.

Concentration is variable in different lots

Supplied in 1x buffer B: 20 mM HEPES-Na (pH 7.9), 20% Glycerol, 42 mM (NH4)2SO4, 0.5 mM DTT and 0.2 mM EDTA
 
References:
1. Ge, H., et al., (1990) Cell 62, 25-34; (1991) Cell 66, 373-382
2. Krainer, A.R., et al., (1990) Cell 62, 35-42; (1991) Cell 66, 383-394
3. Zahler, A.M., et al., (1992) Genes & Dev. 6, 837-847
4. Gui, J.F., et al., (1994) Proc. Natl. Acad. Sci. USA 91, 10824-10828
5. Colwill, K., et al., (1996) EMBO J. 15, 265-275
6. Tange, T.O., et al., (1996) J. Biol. Chem. 271, 10066-10072
7. Mortillaro, M.J., et al., (1997) Proc. Natl. Acad. Sci. USA 93, 8253-8257
8. Benz et al., (2005) Blood, Vol.105, No.5,2146-2153