Fig. 3From: Genome-wide characterization of aspartic protease (AP) gene family in Populus trichocarpa and identification of the potential PtAPs involved in wood formationChromosomal locations and duplicated gene pairs of 67 PtAPs. Each was mapped to the chromosome based on its physical location. The chromosome number (Chr01-Chr19) is indicated at the top. The segmental duplicated gene pairs were connecting with a solid blue line, and tandem duplicated genes were outlined with red color. The scale bar represents 5.0 MbBack to article page