SRP9 and SRP14 are heavily localized in the nucleus. (A) Immunofluorescent analysis of representative logarithmically growing MCF-7 cells transfected with a negative control siRNA for 72 h prior to fixation. Cells were probed with both anti-SRP9 (rabbit) and anti-SRP14 (rabbit) antibodies. Anti-rabbit IgG Alexa Fluor 647 conjugate (CY5 filter) was used for visualization. Cells were counterstained with DAPI. Capturing settings were identical for all images to allow for quantitative analysis. The overlay images are composed of the DNA (DAPI—blue), SRP9 (CY5—red), or SRP14 (CY5—red) channels overlayed. Scale bars indicate 50 µm. (B) Same as for (A) but with SRP14 siRNA (SRP9/SRP14 knockdown). (C) Western blot analysis of the subcellular distribution of SRP9 and SRP14. Subcellular markers were used for loading and fraction specificity with antibodies specific to ACTB (cytoplasmic), LRP5 (membrane bound), and MYC (nuclear).
