Supplementary Figure 2.

Volcano plot of relative signal intensity of proteins identified in the adipocyte secretome. The x-axis denotes log₂ of the ratio of iron/vehicle-treated cells, with proteins to the left of zero representing those down-regulated by iron and those to the right representing up-regulation by iron. The y-axis denotes statistical significance with a line representing a P value of .05. Proteins above this line have a P value <.05. SILAC-labeled adipocytes generated 338 proteins that were identified in the secretome by mass spectrometry. Of these, 213 had reduced signal intensity in response to iron, whereas 125 had increased signal intensity. Of the 213 proteins with reduced signal intensity, 61 had a statistically significant (P < .05) down-regulation in response to iron. Of these, 53 had a greater than 2-fold decrease in response to iron. Of the 125 proteins with increased signal intensity, 11 had a statistically significant (P < .05) up-regulation in response to iron. Of these, 7 proteins had a greater than 2-fold increase response to iron. Those proteins containing signal peptide (as determined by signal peptide annotations on the UniProt database) are shown in red. Those without signal peptide are shown in blue.