Fig. 2: Summary of global 3’ UTR utilization across ~250 Drosophila cell types.

The circular plot summarizes APA trends across 1305 genes that exhibit differential 3’ UTR utilization from neurons, ovary, and testis cells. We used the LABRAT package to calculate ψ across these genes in each of the 242 adult Drosophila cell types annotated by the FCA, grouped according to their tissue origin. Because some cell types are found in multiple tissues, the number of sectors is greater than 242 (e.g., muscle cells, epithelial cells, hemocytes and fat body are present broadly across tissues). We describe the plot features from outside in. The tissue and cell types are shown at the perimeter. Inside this, the behavior of individual genes is shown in heatmap sectors, using the ψ color key shown in the center. The cell types in each tissue are organized by hierarchical clustering. The next ring inside highlights selected general cell types in these colors: neurons (red), testis (blue) and ovary (purple). Finally, the inner sectors plot the average ψ value (re-scaled 0 to 1, two grey dashes demarcate 0.3 and 0.7, respectively) for each cell type across the selected APA genes. From these analyses, several general features regarding cell type-specific APA are evident. Of note, neurons globally express longest/most distal 3’ UTRs of all cell types (red). Reciprocally, the testis contains cell types that utilize the shortest/most proximal 3’ UTRs of all cell types (blue).