Figure 2.
Exon-intron structures of the ZP3-Cancer and ZP3-Oocyte RNA transcripts. The ZP3-Cancer and ZP3-Oocyte RNA transcripts contain 9 and 8 exons respectively, of which exon 3-9 of ZP3-Cancer and 2-8 of ZP3-Oocyte are identical. The 5′-coding part of ZP3-Oocyte exon 1 encodes the N-terminal signal peptide that ensures entry of the ZP3 protein into the secretory pathway. This region is not part of exon 2 of the ZP3-Cancer transcript, and therefore is absent from the ZP3-Cancer mRNA. Exon 1 of ZP3-Cancer is located 27.3 kilobase pairs (kb) upstream of its second exon. Sizes (in kb) of the largest introns are indicated. The arrows indicate the locations of the primers used for transcript-specific detection by qPCR.