Composition of isotigs. Venn diagram showing the number of non-singleton PUTs (i.e. isotigs) consisting of reads from (one or several) libraries of one or more treatment(s). E.g. 21,737 isotigs are composed of reads originating from one or several of the severe stress libraries (DCNS, DINS, DCWS, DIWS). c = control, m = mild stress, s = severe stress.