Fig. 2.

SILAC 2–4: importin 13 binding proteins from HeLa cell extracts. A, Experimental workflow. HZZ-tagged importin 13 was immobilized on IgG-Sepharose and incubated with labeled HeLa cell extracts (“light”, “medium”, “heavy”) supplemented with either RanQ69L, Ubc9 or buffer. B, Scatter plot showing log2-ratios of proteins binding to the importin 13 matrix in the absence or presence of Ubc9 in forward (fwd, y axis) and reverse (rev, x axis) reactions. C, Scatter plot showing log2-ratios of proteins binding to the importin 13 matrix in the presence or absence of RanGTP, with (y axis) or without (x axis) the addition of Ubc9. (B, C) Data are from three independent biological replicates with two experiments under identical labeling conditions (reverse) and one with a label switch (forward). Underlined proteins are known importin 13 cargoes. Proteins highlighted in red (B) and blue (C) but not underlined are cargo candidates that were further analyzed, and were (dark color, filled diamonds) or were not (light color, filled squares) affected by overexpression of importin 13. Gray open squares and gray crosses correspond to importin 13 cargo candidates identified in all three or in two out of three SILAC replicates with a log2 ratio ≥ 0.5, respectively.