Specificity: Detects a sub-set of the non-snRNP splicing factors termed SR proteins. The antibody detects SRp75, SRp55, SRp40 and SRp20 but not SRp30a or b (ASF/SF2, SC-35) proteins. Recognizes approximately 20 distinct nuclear proteins including the U1 70K component of the U1 snRNP and both subunits of U2AF1. Species cross-reactivity (Western Blot): chicken, human, mouse, rabbit, canine, rat, Xenopus. Reactivity has not been detected with yeasts.