Fig. 1

Identification of FGF12 partner proteins. A Recombinant FGF12-His was bound to Ni Sepharose and incubated with U2OS cell lysate. Proteins were eluted with Laemmli sample buffer, separated with SDS-PAGE and stained with CBB. B Top 10 results of identifying proteins by MS that specifically bound to FGF12-His in pull-down experiments. ID is the Uniprot protein identifier, the abbreviated name is also the gene name. The score and peptide match for each of the two repeats of the experiment are given. C FGF12 interaction network identified by affinity purification followed by mass spectrometry. Proteins were classified using STRING database (http://www.string-db.org/). Blue spheres represent nuclear proteins and red spheres represent cytosolic proteins. The lines connecting the spheres represent the experimentally confirmed interactions. D Cellular localization of FGF12. U2OS cells stably expressing FGF12-mGFP-myc (U2OS-FGF12-mGFP-myc) were fixed, then cell nuclei were stained with NucBlue Live, and analyzed with fluorescence microscopy. The dashed line indicates the cell area and the arrows indicate the nucleoli. The scale bar represents 20 μm. The graph shows the mean fluorescence intensity in the nucleus and cytoplasm. Data presented are means ± SD of 20 cells. A paired student’s t-test was used for statistical analysis; ***p < 0.001. E Co-localization of FGF12-mGFP-myc with the nucleolar marker, dyskerin. U2OS-FGF12-mGFP-myc cells were fixed, permeabilized and stained with a primary antibody against dyskerin and Alexa Fluor 594-conjugated anti-mouse secondary antibody. Cell nuclei were labeled with NucBlue Live and cells were analyzed by fluorescence microscopy. The scale bar represents 20 μm. F U2OS-FGF12-mGFP-myc cells were lysed, and nucleoli were isolated by sonication and centrifugation in buffer with increasing sucrose concentration. The presence of FGF12 and NOLC1 in nucleoli was analyzed by immunoblotting. An antibody against γ-tubulin was used to ensure equal loading of the samples.