Fig. 2.

Focused analysis of C. elegans after 16 h of starvation stress. (A) The starvation stress response of ∼5,000 proteins is indicated with the median ratio of each protein group, represented by a spot (n = 3). The y axis shows a p value (-log₁₀ transformed) derived from a Student's t test across the three biological replicates for each protein, compared with the biological replicates of a negative control protein PRO-1. The relative fold change is shown on the x axis using the log₂ SILAC ratio L/H (starved/fed). The mean number of unique peptides on a log₂ scale is represented by the spot diameter, with larger size indicating more unique peptides. Proteins with a p < .05 are shown in red and those with a p < .01 are shown in green. GO term analysis of enriched biological processes within the protein groups whose abundance either increased (B) or decreased (C) after starvation for 16 h. A threshold of more than twofold change and a p < .01 were used and GO term analysis was performed using the DAVID database (29). These data were plotted using the REVIGO suite (30). The x and y axes indicate semantic space used to group GO terms of related biological processes. The color and size of each bubble indicates the EASE score (log₁₀ transformed) for each GO term versus the whole C. elegans proteome. The size increases with increasing log₁₀ (p value) and the color changes from red to blue with increasing log₁₀ (p value). Bubbles that are in close proximity indicate related GO terms.