SFPS colocalizes with U2 small nuclear ribonucleoprotein (snRNP) components in discrete nuclear foci. (A, D, and G) Subcellular localization of SFPS-GFP in tobacco cells. Subcellular localization of U2A′-mCherry (B), U2AF35A-mCherry (E), and U2AF65B-mCherry (H) in tobacco cells. (C, F, and I) Overlay panels from GFP and mCherry channels. (Scale bar, 5 μm.) (J) SFPS-GFP and MYC-U2AF65B proteins coimmunoprecipitate in Arabidopsis. Total proteins are extracted from double-transgenic Arabidopsis seedlings coexpressing SFPS-GFP and MYC-U2AF65B proteins. IP samples were pulled down with anti-GFP antibody and probed with anti-MYC and anti-GFP antibodies, respectively. Anti-IgG was used as a negative control. Dk, dark; Rc, continuous red.