Fig. 3

Tissue-specific variation in 3′UTR lengths. a PAS site usage for genes with a single or multiple 3′UTRs. The canonical PAS motif (AAUAAA) is the most prevalent and is strongly preferred for genes with a single 3′UTR isoform. b Distribution of 3′UTR lengths in different samples. 3′UTRs are dramatically shorter in male vs. female germline. Within the female germline, 3′UTR isoforms are shorter in proliferating mitotic nuclei and longest in oocytes. Highly abundant transcripts for ribosomal and major sperm proteins were excluded from this analysis. c Alternative polyadenylation in male and female germline. Genes expressed in both male and female germline show significantly different isoform usage: typically, more proximal isoforms are selected in male and more distal isoforms are selected in female. Each point represents the major isoform for a particular gene, short (red) or long (green), expressed in male (below the diagonal) or female (above the diagonal), along with its relative usage in male vs. female (as percentage of total isoform abundance in each); 5% quadrants are shaded by density of isoform type. Red points in the bottom right quadrant signify that the shortest isoforms for those genes are dominant in the male germline and used less than half the time in the female germline, whereas green points in the top left quadrant indicate the converse (>50% usage of the longest isoform in female and <50% usage in male germline)