Functional categories of genes with antisense transcripts and confirmation of sense-antisense pairs of various genes expressed in human hepatocytes. A. Genes with antisense transcripts were assigned into different functional categories according to the Gene Ontology (GO) database. B. Functional over- or under-representation of GO subcategories in genes with antisense transcripts was statistically analyzed using FatiGO+ classification tool, as compared to genes without detectable antisense transcripts (p < 0.05). Red boxes indicated the GO subcategories related to genes with antisense transcripts; Green ones indicated the subcategories related to genes without detectable antisense transcripts. C. Sketch map of specific PCR primers designed for detecting both sense and antisense of various genes. The cross signs between antisense and sense transcripts represent complementarity each other, whereas the vertical bars indicate identical base pairs. Reverse transcription was performed using the specific primers (Primer_F1 for the antisense transcripts) that only hybridize to the sense or antisense transcripts. D. The sense and antisense transcripts of APOC2, APOB, APOH, APOC1 were amplified by RT-PCR using specific primers, where primers F1 and R2 were used for the sense transcripts (lane 1) and primers F1 and R1 for the antisense transcripts (lane 3). Lanes 2 and 4 were negative controls without cDNA synthesis (with DNase-treated total RNA). The two genes (TMEM37 and LASS5) without antisense counterparts were served as the set of negative control.