Figure 1.

Construction pipeline of the APAatlas database. RNA-seq raw data, gene expression and traits involved in 53 human tissues were collected from the Genotype-Tissue Expression (GTEx) portal. Two algorithms were used to quantify alternative polyadenylation (APA) usage: The percentage of distal poly(A) site usage index (PDUI) was de novo identified by DaPars; the relative expression difference (RED) was quantified by the annotation-based algorithm SAAP-RS and further filtered by sample size and APA events for subsequent analysis. Users can query the APA landscape, trait relevance, and gene expression correlation in three modules and download APA usage matrixes.