Mouse Anti-SR Proteins (Non-snRNP Splicing Factor) (Biotin)
SR proteins are a highly conserved family of arginine/serine rich, spliceosome associated phosphoproteins essential for metazoan pre-mRNA splicing. SR proteins appear to act early in splicing by promoting splice site recognition and spliceosome assembly. SR proteins also play a regulatory role, because they can determine alternative splice site usage in vivo and in vitro-a particularly interesting example is the regulation of adenovirus alternative RNA splicing by dephosphorylation of SR proteins. SR proteins appear to be recruited from nuclear “speckles”, in which they are concentrated, to sites of transcription in order to spatially coordinate transcription and pre-mRNA splicing within the cell nucleus.
The epitope detected by the antibody has been termed the “alternating arginine domain” and is composed almost exclusively of argnine alternating with glutamate and aspartate. Antibody targets are predominantly nuclear, nonnucleolar, and are localized to active sites of polymerase II transcription. Epitope is conserved in metazoans.
Applications
Suitable for use in Immunofluorescence/Immunocytochemistry, ELISA and Western Blot. Other applications not tested.
Recommended Dilutions
Optimal dilutions to be determined by the researcher.
Positive Controls
HeLa cell, nuclear extracts
Storage and Stability
Store product at 4°C if to be used immediately within two weeks. For long-term storage, aliquot to avoid repeated freezing and thawing and store at -20°C. Aliquots are stable at -20°C for 12 months after receipt. Dilute required amount only prior to immediate use. Further dilutions can be made in assay buffer. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
Note: Applications are based on unconjugated antibody.
Immunogen
Purified, de-phosphorylated bovine Srp55 and Drosophila p55-GST. The epitope has been mapped to a 40 amino acid polypeptide composed almost exclusively of arginine alternating with glutamate and aspartate.
Form
Supplied as a liquid in PBS, pH 7.2. No preservatives added. Labeled with Biotin.
Purity
Purified by Protein A affinity chromatography
Specificity
Recognizes a sub-set of the non-snRNP splicing factors termed SR proteins. Detects SRp75, SRp55, SRp40 and SRp20 but not SRp30a or b (ASF/SF2, SC-35) proteins. Recognizes ~20 distinct nuclear proteins including the U1 70K component of the U1 snRNP and both subunits of U2AF1. Species Crossreactivity: chicken, human, mouse, rabbit, canine, rat, Xenopus. Reactivity has not been detected with yeasts.
